CB Radio or PRS
Guest
Posts: n/a
Re: CB Radio or PRS - Update -(long & semi OT)
Mike, I hope I didn't come across the wrong way on this, I have no
desire to start a flame war over this. You have, IMHO, a well
deserved reputation on this group for knowing your stuff, but I still
think you're wrong.
My position on this comes from being an electronics technician
working in the radio field for somewheres on the upper side of 30
years. An awful lot of that time has been spent testing &
troubleshooting antenna & transmission lines on everything from
microwave relay links to CBs, with a bunch of cell tower & military
stuff in between. I think by now I'm pretty well grounded in both the
theory & the practice.
As far as CBs are concerned, if your antenna is properly designed &
installed then the length of the coax line & whether or not the coax
is coiled up is immaterial to the operation of the system. If there's
a problem with the installation then you may well have problems with
the coax radiating the reflected power that was supposed to go out the
antenna. You may also experience the signal trying to get to ground
through you power cabling instead of the coax shield. In this case
you may well have interferance problems inside the vehicle & changing
the length of the coax may affect your SWR meter's reading, but
changing the length to make the meter read "right" is really only
covering up the problem. The best way to check the SWR is with the
meter inserted into the line right at the antenna, unfortunately the
way most antennas are built makes this difficult. To get the real
picture of whats happening from the radio end of the line requires an
antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
did I mention "$$$"?).
I saw what you said about the problems you were having with your fleet
vehicles & the data systems, I've seen it too. When the digital
"TDMA" vehicle mount cell phones came out, we really had to crack down
on the installers to get the VSWR down as far as possible, otherwise
the bit error rate went crazy. We also made them trim the coax to
"just long enough" in order to eliminate the loss from the extra
length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
If your SWR is high & you can't do anything about the antenna then you
can reduce to problems inside the vehicle by (gasp) looping the coax a
few times at the antenna to form an rf choke, this prevents the
reflected signal from travelling back down the outside of the coax.
Another trick that works is to get one of those ferrite sleeves that
you see showing up on power & telephone cables these days. Stick it
over the coax at the base of the antenna & it'll do the same thing as
the loops. Running the power leads through one of these things
wouldn't hurt either.
Tell ya what- next time you're in Halifax drop me a note, I'll get
some test equipment togeather & I'll try to show to prove to you in
person what I'm saying is right. If I'm wrong I'll buy you a 24, If
I'm right you do the buying, How's that?
-Howard.
p.s.- I drink Keith's :).
On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
wrote:
>You are mistaken.
>
>The coil can act as a pickup for noise and it can put out RF.
>
>You should really read the TSB out on how to install a transmitter into
>a new modern vehicle or you will void your vehicle warranty.
>
>The antenna cable can and will interfere with the vehicle's onboard
>electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
>Jeep automatic tranny module so every time you key up you go into
>neutral. It also will interfere with the fuel injectors.
>
>GM, Chrysler and all the rest have booklets out now on how to properly
>wire a transmitter in order to avoid voiding the vehicle warranty.
>
>GM insists on minimum 10 ga. power and ground run right to the battery
>and double fused there on the opposite side of the vehicle from the
>wiring harness. The antenna must run on the opposite side from the
>harness too.
>
>So for the power lines, to have a CB on the center or passenger side of
>a GM van, the wires have to run up the passenger side fender to the
>front of the vehicle, across the front of the radiator supports and back
>to the battery. If you run them across the firewall, you void the
>warranty for the vehicle's electronics, all of them.
>
>Mike
>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>88 Cherokee 235 BFG AT's
>
>Howard Eisenhauer wrote:
>>
>> TW, another old wive's tale about the coiled coax thing. If
>> everything is working the way it should all the signal travels through
>> the coax between the center conductor & the inside of the braid, not
>> along the outside where coiling it would have any effect. Coiling it,
>> tying it up or crocheting it for that matter will not make any
>> differencet :). There are actually some situations where coiling it
>> up would make a system work better, but you won't run into them in a
>> jeep using a commercially available antenna.
>>
>> Howard.
>>
>> On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
>> <thomas@OBVIOUSrubicons.com> wrote:
>>
>> >The rule of thumb is to be 3 ft. from any other antennas. Shortening
>> >your coax run in your TJ is not going to help your transmit range. Just
>> >make sure you don't leave a coil of coax somewhere.
>> >
>> >TW wrote:
>> >
>> >> I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
>> >> will be spent installing it.
>> >>
>> >> I was thinking how would it look if I could somehow install the CB antenna
>> >> on the exact opposite side of the radio antenna (same height and spot). My
>> >> radio antenna is on the right side of the TJ, CB antenna on the left side
>> >> would ensure coax is shortest and the antenna would be somewhat in the
>> >> middle of the truck (though to one side). Any ideas or photos of such an
>> >> install?
>> >>
>> >> Thanks for all the help guys. Its much appreciated.
desire to start a flame war over this. You have, IMHO, a well
deserved reputation on this group for knowing your stuff, but I still
think you're wrong.
My position on this comes from being an electronics technician
working in the radio field for somewheres on the upper side of 30
years. An awful lot of that time has been spent testing &
troubleshooting antenna & transmission lines on everything from
microwave relay links to CBs, with a bunch of cell tower & military
stuff in between. I think by now I'm pretty well grounded in both the
theory & the practice.
As far as CBs are concerned, if your antenna is properly designed &
installed then the length of the coax line & whether or not the coax
is coiled up is immaterial to the operation of the system. If there's
a problem with the installation then you may well have problems with
the coax radiating the reflected power that was supposed to go out the
antenna. You may also experience the signal trying to get to ground
through you power cabling instead of the coax shield. In this case
you may well have interferance problems inside the vehicle & changing
the length of the coax may affect your SWR meter's reading, but
changing the length to make the meter read "right" is really only
covering up the problem. The best way to check the SWR is with the
meter inserted into the line right at the antenna, unfortunately the
way most antennas are built makes this difficult. To get the real
picture of whats happening from the radio end of the line requires an
antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
did I mention "$$$"?).
I saw what you said about the problems you were having with your fleet
vehicles & the data systems, I've seen it too. When the digital
"TDMA" vehicle mount cell phones came out, we really had to crack down
on the installers to get the VSWR down as far as possible, otherwise
the bit error rate went crazy. We also made them trim the coax to
"just long enough" in order to eliminate the loss from the extra
length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
If your SWR is high & you can't do anything about the antenna then you
can reduce to problems inside the vehicle by (gasp) looping the coax a
few times at the antenna to form an rf choke, this prevents the
reflected signal from travelling back down the outside of the coax.
Another trick that works is to get one of those ferrite sleeves that
you see showing up on power & telephone cables these days. Stick it
over the coax at the base of the antenna & it'll do the same thing as
the loops. Running the power leads through one of these things
wouldn't hurt either.
Tell ya what- next time you're in Halifax drop me a note, I'll get
some test equipment togeather & I'll try to show to prove to you in
person what I'm saying is right. If I'm wrong I'll buy you a 24, If
I'm right you do the buying, How's that?
-Howard.
p.s.- I drink Keith's :).
On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
wrote:
>You are mistaken.
>
>The coil can act as a pickup for noise and it can put out RF.
>
>You should really read the TSB out on how to install a transmitter into
>a new modern vehicle or you will void your vehicle warranty.
>
>The antenna cable can and will interfere with the vehicle's onboard
>electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
>Jeep automatic tranny module so every time you key up you go into
>neutral. It also will interfere with the fuel injectors.
>
>GM, Chrysler and all the rest have booklets out now on how to properly
>wire a transmitter in order to avoid voiding the vehicle warranty.
>
>GM insists on minimum 10 ga. power and ground run right to the battery
>and double fused there on the opposite side of the vehicle from the
>wiring harness. The antenna must run on the opposite side from the
>harness too.
>
>So for the power lines, to have a CB on the center or passenger side of
>a GM van, the wires have to run up the passenger side fender to the
>front of the vehicle, across the front of the radiator supports and back
>to the battery. If you run them across the firewall, you void the
>warranty for the vehicle's electronics, all of them.
>
>Mike
>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>88 Cherokee 235 BFG AT's
>
>Howard Eisenhauer wrote:
>>
>> TW, another old wive's tale about the coiled coax thing. If
>> everything is working the way it should all the signal travels through
>> the coax between the center conductor & the inside of the braid, not
>> along the outside where coiling it would have any effect. Coiling it,
>> tying it up or crocheting it for that matter will not make any
>> differencet :). There are actually some situations where coiling it
>> up would make a system work better, but you won't run into them in a
>> jeep using a commercially available antenna.
>>
>> Howard.
>>
>> On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
>> <thomas@OBVIOUSrubicons.com> wrote:
>>
>> >The rule of thumb is to be 3 ft. from any other antennas. Shortening
>> >your coax run in your TJ is not going to help your transmit range. Just
>> >make sure you don't leave a coil of coax somewhere.
>> >
>> >TW wrote:
>> >
>> >> I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
>> >> will be spent installing it.
>> >>
>> >> I was thinking how would it look if I could somehow install the CB antenna
>> >> on the exact opposite side of the radio antenna (same height and spot). My
>> >> radio antenna is on the right side of the TJ, CB antenna on the left side
>> >> would ensure coax is shortest and the antenna would be somewhat in the
>> >> middle of the truck (though to one side). Any ideas or photos of such an
>> >> install?
>> >>
>> >> Thanks for all the help guys. Its much appreciated.
Guest
Posts: n/a
Re: CB Radio or PRS - Update -(long & semi OT)
Mike, I hope I didn't come across the wrong way on this, I have no
desire to start a flame war over this. You have, IMHO, a well
deserved reputation on this group for knowing your stuff, but I still
think you're wrong.
My position on this comes from being an electronics technician
working in the radio field for somewheres on the upper side of 30
years. An awful lot of that time has been spent testing &
troubleshooting antenna & transmission lines on everything from
microwave relay links to CBs, with a bunch of cell tower & military
stuff in between. I think by now I'm pretty well grounded in both the
theory & the practice.
As far as CBs are concerned, if your antenna is properly designed &
installed then the length of the coax line & whether or not the coax
is coiled up is immaterial to the operation of the system. If there's
a problem with the installation then you may well have problems with
the coax radiating the reflected power that was supposed to go out the
antenna. You may also experience the signal trying to get to ground
through you power cabling instead of the coax shield. In this case
you may well have interferance problems inside the vehicle & changing
the length of the coax may affect your SWR meter's reading, but
changing the length to make the meter read "right" is really only
covering up the problem. The best way to check the SWR is with the
meter inserted into the line right at the antenna, unfortunately the
way most antennas are built makes this difficult. To get the real
picture of whats happening from the radio end of the line requires an
antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
did I mention "$$$"?).
I saw what you said about the problems you were having with your fleet
vehicles & the data systems, I've seen it too. When the digital
"TDMA" vehicle mount cell phones came out, we really had to crack down
on the installers to get the VSWR down as far as possible, otherwise
the bit error rate went crazy. We also made them trim the coax to
"just long enough" in order to eliminate the loss from the extra
length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
If your SWR is high & you can't do anything about the antenna then you
can reduce to problems inside the vehicle by (gasp) looping the coax a
few times at the antenna to form an rf choke, this prevents the
reflected signal from travelling back down the outside of the coax.
Another trick that works is to get one of those ferrite sleeves that
you see showing up on power & telephone cables these days. Stick it
over the coax at the base of the antenna & it'll do the same thing as
the loops. Running the power leads through one of these things
wouldn't hurt either.
Tell ya what- next time you're in Halifax drop me a note, I'll get
some test equipment togeather & I'll try to show to prove to you in
person what I'm saying is right. If I'm wrong I'll buy you a 24, If
I'm right you do the buying, How's that?
-Howard.
p.s.- I drink Keith's :).
On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
wrote:
>You are mistaken.
>
>The coil can act as a pickup for noise and it can put out RF.
>
>You should really read the TSB out on how to install a transmitter into
>a new modern vehicle or you will void your vehicle warranty.
>
>The antenna cable can and will interfere with the vehicle's onboard
>electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
>Jeep automatic tranny module so every time you key up you go into
>neutral. It also will interfere with the fuel injectors.
>
>GM, Chrysler and all the rest have booklets out now on how to properly
>wire a transmitter in order to avoid voiding the vehicle warranty.
>
>GM insists on minimum 10 ga. power and ground run right to the battery
>and double fused there on the opposite side of the vehicle from the
>wiring harness. The antenna must run on the opposite side from the
>harness too.
>
>So for the power lines, to have a CB on the center or passenger side of
>a GM van, the wires have to run up the passenger side fender to the
>front of the vehicle, across the front of the radiator supports and back
>to the battery. If you run them across the firewall, you void the
>warranty for the vehicle's electronics, all of them.
>
>Mike
>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>88 Cherokee 235 BFG AT's
>
>Howard Eisenhauer wrote:
>>
>> TW, another old wive's tale about the coiled coax thing. If
>> everything is working the way it should all the signal travels through
>> the coax between the center conductor & the inside of the braid, not
>> along the outside where coiling it would have any effect. Coiling it,
>> tying it up or crocheting it for that matter will not make any
>> differencet :). There are actually some situations where coiling it
>> up would make a system work better, but you won't run into them in a
>> jeep using a commercially available antenna.
>>
>> Howard.
>>
>> On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
>> <thomas@OBVIOUSrubicons.com> wrote:
>>
>> >The rule of thumb is to be 3 ft. from any other antennas. Shortening
>> >your coax run in your TJ is not going to help your transmit range. Just
>> >make sure you don't leave a coil of coax somewhere.
>> >
>> >TW wrote:
>> >
>> >> I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
>> >> will be spent installing it.
>> >>
>> >> I was thinking how would it look if I could somehow install the CB antenna
>> >> on the exact opposite side of the radio antenna (same height and spot). My
>> >> radio antenna is on the right side of the TJ, CB antenna on the left side
>> >> would ensure coax is shortest and the antenna would be somewhat in the
>> >> middle of the truck (though to one side). Any ideas or photos of such an
>> >> install?
>> >>
>> >> Thanks for all the help guys. Its much appreciated.
desire to start a flame war over this. You have, IMHO, a well
deserved reputation on this group for knowing your stuff, but I still
think you're wrong.
My position on this comes from being an electronics technician
working in the radio field for somewheres on the upper side of 30
years. An awful lot of that time has been spent testing &
troubleshooting antenna & transmission lines on everything from
microwave relay links to CBs, with a bunch of cell tower & military
stuff in between. I think by now I'm pretty well grounded in both the
theory & the practice.
As far as CBs are concerned, if your antenna is properly designed &
installed then the length of the coax line & whether or not the coax
is coiled up is immaterial to the operation of the system. If there's
a problem with the installation then you may well have problems with
the coax radiating the reflected power that was supposed to go out the
antenna. You may also experience the signal trying to get to ground
through you power cabling instead of the coax shield. In this case
you may well have interferance problems inside the vehicle & changing
the length of the coax may affect your SWR meter's reading, but
changing the length to make the meter read "right" is really only
covering up the problem. The best way to check the SWR is with the
meter inserted into the line right at the antenna, unfortunately the
way most antennas are built makes this difficult. To get the real
picture of whats happening from the radio end of the line requires an
antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
did I mention "$$$"?).
I saw what you said about the problems you were having with your fleet
vehicles & the data systems, I've seen it too. When the digital
"TDMA" vehicle mount cell phones came out, we really had to crack down
on the installers to get the VSWR down as far as possible, otherwise
the bit error rate went crazy. We also made them trim the coax to
"just long enough" in order to eliminate the loss from the extra
length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
If your SWR is high & you can't do anything about the antenna then you
can reduce to problems inside the vehicle by (gasp) looping the coax a
few times at the antenna to form an rf choke, this prevents the
reflected signal from travelling back down the outside of the coax.
Another trick that works is to get one of those ferrite sleeves that
you see showing up on power & telephone cables these days. Stick it
over the coax at the base of the antenna & it'll do the same thing as
the loops. Running the power leads through one of these things
wouldn't hurt either.
Tell ya what- next time you're in Halifax drop me a note, I'll get
some test equipment togeather & I'll try to show to prove to you in
person what I'm saying is right. If I'm wrong I'll buy you a 24, If
I'm right you do the buying, How's that?
-Howard.
p.s.- I drink Keith's :).
On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
wrote:
>You are mistaken.
>
>The coil can act as a pickup for noise and it can put out RF.
>
>You should really read the TSB out on how to install a transmitter into
>a new modern vehicle or you will void your vehicle warranty.
>
>The antenna cable can and will interfere with the vehicle's onboard
>electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
>Jeep automatic tranny module so every time you key up you go into
>neutral. It also will interfere with the fuel injectors.
>
>GM, Chrysler and all the rest have booklets out now on how to properly
>wire a transmitter in order to avoid voiding the vehicle warranty.
>
>GM insists on minimum 10 ga. power and ground run right to the battery
>and double fused there on the opposite side of the vehicle from the
>wiring harness. The antenna must run on the opposite side from the
>harness too.
>
>So for the power lines, to have a CB on the center or passenger side of
>a GM van, the wires have to run up the passenger side fender to the
>front of the vehicle, across the front of the radiator supports and back
>to the battery. If you run them across the firewall, you void the
>warranty for the vehicle's electronics, all of them.
>
>Mike
>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>88 Cherokee 235 BFG AT's
>
>Howard Eisenhauer wrote:
>>
>> TW, another old wive's tale about the coiled coax thing. If
>> everything is working the way it should all the signal travels through
>> the coax between the center conductor & the inside of the braid, not
>> along the outside where coiling it would have any effect. Coiling it,
>> tying it up or crocheting it for that matter will not make any
>> differencet :). There are actually some situations where coiling it
>> up would make a system work better, but you won't run into them in a
>> jeep using a commercially available antenna.
>>
>> Howard.
>>
>> On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
>> <thomas@OBVIOUSrubicons.com> wrote:
>>
>> >The rule of thumb is to be 3 ft. from any other antennas. Shortening
>> >your coax run in your TJ is not going to help your transmit range. Just
>> >make sure you don't leave a coil of coax somewhere.
>> >
>> >TW wrote:
>> >
>> >> I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
>> >> will be spent installing it.
>> >>
>> >> I was thinking how would it look if I could somehow install the CB antenna
>> >> on the exact opposite side of the radio antenna (same height and spot). My
>> >> radio antenna is on the right side of the TJ, CB antenna on the left side
>> >> would ensure coax is shortest and the antenna would be somewhat in the
>> >> middle of the truck (though to one side). Any ideas or photos of such an
>> >> install?
>> >>
>> >> Thanks for all the help guys. Its much appreciated.
Guest
Posts: n/a
Re: CB Radio or PRS - Update -(long & semi OT)
Mike, I hope I didn't come across the wrong way on this, I have no
desire to start a flame war over this. You have, IMHO, a well
deserved reputation on this group for knowing your stuff, but I still
think you're wrong.
My position on this comes from being an electronics technician
working in the radio field for somewheres on the upper side of 30
years. An awful lot of that time has been spent testing &
troubleshooting antenna & transmission lines on everything from
microwave relay links to CBs, with a bunch of cell tower & military
stuff in between. I think by now I'm pretty well grounded in both the
theory & the practice.
As far as CBs are concerned, if your antenna is properly designed &
installed then the length of the coax line & whether or not the coax
is coiled up is immaterial to the operation of the system. If there's
a problem with the installation then you may well have problems with
the coax radiating the reflected power that was supposed to go out the
antenna. You may also experience the signal trying to get to ground
through you power cabling instead of the coax shield. In this case
you may well have interferance problems inside the vehicle & changing
the length of the coax may affect your SWR meter's reading, but
changing the length to make the meter read "right" is really only
covering up the problem. The best way to check the SWR is with the
meter inserted into the line right at the antenna, unfortunately the
way most antennas are built makes this difficult. To get the real
picture of whats happening from the radio end of the line requires an
antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
did I mention "$$$"?).
I saw what you said about the problems you were having with your fleet
vehicles & the data systems, I've seen it too. When the digital
"TDMA" vehicle mount cell phones came out, we really had to crack down
on the installers to get the VSWR down as far as possible, otherwise
the bit error rate went crazy. We also made them trim the coax to
"just long enough" in order to eliminate the loss from the extra
length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
If your SWR is high & you can't do anything about the antenna then you
can reduce to problems inside the vehicle by (gasp) looping the coax a
few times at the antenna to form an rf choke, this prevents the
reflected signal from travelling back down the outside of the coax.
Another trick that works is to get one of those ferrite sleeves that
you see showing up on power & telephone cables these days. Stick it
over the coax at the base of the antenna & it'll do the same thing as
the loops. Running the power leads through one of these things
wouldn't hurt either.
Tell ya what- next time you're in Halifax drop me a note, I'll get
some test equipment togeather & I'll try to show to prove to you in
person what I'm saying is right. If I'm wrong I'll buy you a 24, If
I'm right you do the buying, How's that?
-Howard.
p.s.- I drink Keith's :).
On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
wrote:
>You are mistaken.
>
>The coil can act as a pickup for noise and it can put out RF.
>
>You should really read the TSB out on how to install a transmitter into
>a new modern vehicle or you will void your vehicle warranty.
>
>The antenna cable can and will interfere with the vehicle's onboard
>electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
>Jeep automatic tranny module so every time you key up you go into
>neutral. It also will interfere with the fuel injectors.
>
>GM, Chrysler and all the rest have booklets out now on how to properly
>wire a transmitter in order to avoid voiding the vehicle warranty.
>
>GM insists on minimum 10 ga. power and ground run right to the battery
>and double fused there on the opposite side of the vehicle from the
>wiring harness. The antenna must run on the opposite side from the
>harness too.
>
>So for the power lines, to have a CB on the center or passenger side of
>a GM van, the wires have to run up the passenger side fender to the
>front of the vehicle, across the front of the radiator supports and back
>to the battery. If you run them across the firewall, you void the
>warranty for the vehicle's electronics, all of them.
>
>Mike
>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>88 Cherokee 235 BFG AT's
>
>Howard Eisenhauer wrote:
>>
>> TW, another old wive's tale about the coiled coax thing. If
>> everything is working the way it should all the signal travels through
>> the coax between the center conductor & the inside of the braid, not
>> along the outside where coiling it would have any effect. Coiling it,
>> tying it up or crocheting it for that matter will not make any
>> differencet :). There are actually some situations where coiling it
>> up would make a system work better, but you won't run into them in a
>> jeep using a commercially available antenna.
>>
>> Howard.
>>
>> On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
>> <thomas@OBVIOUSrubicons.com> wrote:
>>
>> >The rule of thumb is to be 3 ft. from any other antennas. Shortening
>> >your coax run in your TJ is not going to help your transmit range. Just
>> >make sure you don't leave a coil of coax somewhere.
>> >
>> >TW wrote:
>> >
>> >> I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
>> >> will be spent installing it.
>> >>
>> >> I was thinking how would it look if I could somehow install the CB antenna
>> >> on the exact opposite side of the radio antenna (same height and spot). My
>> >> radio antenna is on the right side of the TJ, CB antenna on the left side
>> >> would ensure coax is shortest and the antenna would be somewhat in the
>> >> middle of the truck (though to one side). Any ideas or photos of such an
>> >> install?
>> >>
>> >> Thanks for all the help guys. Its much appreciated.
desire to start a flame war over this. You have, IMHO, a well
deserved reputation on this group for knowing your stuff, but I still
think you're wrong.
My position on this comes from being an electronics technician
working in the radio field for somewheres on the upper side of 30
years. An awful lot of that time has been spent testing &
troubleshooting antenna & transmission lines on everything from
microwave relay links to CBs, with a bunch of cell tower & military
stuff in between. I think by now I'm pretty well grounded in both the
theory & the practice.
As far as CBs are concerned, if your antenna is properly designed &
installed then the length of the coax line & whether or not the coax
is coiled up is immaterial to the operation of the system. If there's
a problem with the installation then you may well have problems with
the coax radiating the reflected power that was supposed to go out the
antenna. You may also experience the signal trying to get to ground
through you power cabling instead of the coax shield. In this case
you may well have interferance problems inside the vehicle & changing
the length of the coax may affect your SWR meter's reading, but
changing the length to make the meter read "right" is really only
covering up the problem. The best way to check the SWR is with the
meter inserted into the line right at the antenna, unfortunately the
way most antennas are built makes this difficult. To get the real
picture of whats happening from the radio end of the line requires an
antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
did I mention "$$$"?).
I saw what you said about the problems you were having with your fleet
vehicles & the data systems, I've seen it too. When the digital
"TDMA" vehicle mount cell phones came out, we really had to crack down
on the installers to get the VSWR down as far as possible, otherwise
the bit error rate went crazy. We also made them trim the coax to
"just long enough" in order to eliminate the loss from the extra
length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
If your SWR is high & you can't do anything about the antenna then you
can reduce to problems inside the vehicle by (gasp) looping the coax a
few times at the antenna to form an rf choke, this prevents the
reflected signal from travelling back down the outside of the coax.
Another trick that works is to get one of those ferrite sleeves that
you see showing up on power & telephone cables these days. Stick it
over the coax at the base of the antenna & it'll do the same thing as
the loops. Running the power leads through one of these things
wouldn't hurt either.
Tell ya what- next time you're in Halifax drop me a note, I'll get
some test equipment togeather & I'll try to show to prove to you in
person what I'm saying is right. If I'm wrong I'll buy you a 24, If
I'm right you do the buying, How's that?
-Howard.
p.s.- I drink Keith's :).
On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
wrote:
>You are mistaken.
>
>The coil can act as a pickup for noise and it can put out RF.
>
>You should really read the TSB out on how to install a transmitter into
>a new modern vehicle or you will void your vehicle warranty.
>
>The antenna cable can and will interfere with the vehicle's onboard
>electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
>Jeep automatic tranny module so every time you key up you go into
>neutral. It also will interfere with the fuel injectors.
>
>GM, Chrysler and all the rest have booklets out now on how to properly
>wire a transmitter in order to avoid voiding the vehicle warranty.
>
>GM insists on minimum 10 ga. power and ground run right to the battery
>and double fused there on the opposite side of the vehicle from the
>wiring harness. The antenna must run on the opposite side from the
>harness too.
>
>So for the power lines, to have a CB on the center or passenger side of
>a GM van, the wires have to run up the passenger side fender to the
>front of the vehicle, across the front of the radiator supports and back
>to the battery. If you run them across the firewall, you void the
>warranty for the vehicle's electronics, all of them.
>
>Mike
>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>88 Cherokee 235 BFG AT's
>
>Howard Eisenhauer wrote:
>>
>> TW, another old wive's tale about the coiled coax thing. If
>> everything is working the way it should all the signal travels through
>> the coax between the center conductor & the inside of the braid, not
>> along the outside where coiling it would have any effect. Coiling it,
>> tying it up or crocheting it for that matter will not make any
>> differencet :). There are actually some situations where coiling it
>> up would make a system work better, but you won't run into them in a
>> jeep using a commercially available antenna.
>>
>> Howard.
>>
>> On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
>> <thomas@OBVIOUSrubicons.com> wrote:
>>
>> >The rule of thumb is to be 3 ft. from any other antennas. Shortening
>> >your coax run in your TJ is not going to help your transmit range. Just
>> >make sure you don't leave a coil of coax somewhere.
>> >
>> >TW wrote:
>> >
>> >> I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
>> >> will be spent installing it.
>> >>
>> >> I was thinking how would it look if I could somehow install the CB antenna
>> >> on the exact opposite side of the radio antenna (same height and spot). My
>> >> radio antenna is on the right side of the TJ, CB antenna on the left side
>> >> would ensure coax is shortest and the antenna would be somewhat in the
>> >> middle of the truck (though to one side). Any ideas or photos of such an
>> >> install?
>> >>
>> >> Thanks for all the help guys. Its much appreciated.
Guest
Posts: n/a
Re: CB Radio or PRS - Update -(long & semi OT)
I concur!
What you describe is absolutely correct by my experience.
The real trick is to get the antenna to match the xmtrs' rated load
Typically 50 ohms unbalanced.
Howard Eisenhauer wrote:
> Mike, I hope I didn't come across the wrong way on this, I have no
> desire to start a flame war over this. You have, IMHO, a well
> deserved reputation on this group for knowing your stuff, but I still
> think you're wrong.
>
> My position on this comes from being an electronics technician
> working in the radio field for somewheres on the upper side of 30
> years. An awful lot of that time has been spent testing &
> troubleshooting antenna & transmission lines on everything from
> microwave relay links to CBs, with a bunch of cell tower & military
> stuff in between. I think by now I'm pretty well grounded in both the
> theory & the practice.
>
> As far as CBs are concerned, if your antenna is properly designed &
> installed then the length of the coax line & whether or not the coax
> is coiled up is immaterial to the operation of the system. If there's
> a problem with the installation then you may well have problems with
> the coax radiating the reflected power that was supposed to go out the
> antenna. You may also experience the signal trying to get to ground
> through you power cabling instead of the coax shield. In this case
> you may well have interferance problems inside the vehicle & changing
> the length of the coax may affect your SWR meter's reading, but
> changing the length to make the meter read "right" is really only
> covering up the problem. The best way to check the SWR is with the
> meter inserted into the line right at the antenna, unfortunately the
> way most antennas are built makes this difficult. To get the real
> picture of whats happening from the radio end of the line requires an
> antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
> did I mention "$$$"?).
>
> I saw what you said about the problems you were having with your fleet
> vehicles & the data systems, I've seen it too. When the digital
> "TDMA" vehicle mount cell phones came out, we really had to crack down
> on the installers to get the VSWR down as far as possible, otherwise
> the bit error rate went crazy. We also made them trim the coax to
> "just long enough" in order to eliminate the loss from the extra
> length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
>
> If your SWR is high & you can't do anything about the antenna then you
> can reduce to problems inside the vehicle by (gasp) looping the coax a
> few times at the antenna to form an rf choke, this prevents the
> reflected signal from travelling back down the outside of the coax.
> Another trick that works is to get one of those ferrite sleeves that
> you see showing up on power & telephone cables these days. Stick it
> over the coax at the base of the antenna & it'll do the same thing as
> the loops. Running the power leads through one of these things
> wouldn't hurt either.
>
> Tell ya what- next time you're in Halifax drop me a note, I'll get
> some test equipment togeather & I'll try to show to prove to you in
> person what I'm saying is right. If I'm wrong I'll buy you a 24, If
> I'm right you do the buying, How's that?
>
> -Howard.
>
> p.s.- I drink Keith's :).
>
>
> On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
> wrote:
>
>
>>You are mistaken.
>>
>>The coil can act as a pickup for noise and it can put out RF.
>>
>>You should really read the TSB out on how to install a transmitter into
>>a new modern vehicle or you will void your vehicle warranty.
>>
>>The antenna cable can and will interfere with the vehicle's onboard
>>electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
>>Jeep automatic tranny module so every time you key up you go into
>>neutral. It also will interfere with the fuel injectors.
>>
>>GM, Chrysler and all the rest have booklets out now on how to properly
>>wire a transmitter in order to avoid voiding the vehicle warranty.
>>
>>GM insists on minimum 10 ga. power and ground run right to the battery
>>and double fused there on the opposite side of the vehicle from the
>>wiring harness. The antenna must run on the opposite side from the
>>harness too.
>>
>>So for the power lines, to have a CB on the center or passenger side of
>>a GM van, the wires have to run up the passenger side fender to the
>>front of the vehicle, across the front of the radiator supports and back
>>to the battery. If you run them across the firewall, you void the
>>warranty for the vehicle's electronics, all of them.
>>
>>Mike
>>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>>88 Cherokee 235 BFG AT's
>>
>>Howard Eisenhauer wrote:
>>
>>>TW, another old wive's tale about the coiled coax thing. If
>>>everything is working the way it should all the signal travels through
>>>the coax between the center conductor & the inside of the braid, not
>>>along the outside where coiling it would have any effect. Coiling it,
>>>tying it up or crocheting it for that matter will not make any
>>>differencet :). There are actually some situations where coiling it
>>>up would make a system work better, but you won't run into them in a
>>>jeep using a commercially available antenna.
>>>
>>>Howard.
>>>
>>>On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
>>><thomas@OBVIOUSrubicons.com> wrote:
>>>
>>>
>>>>The rule of thumb is to be 3 ft. from any other antennas. Shortening
>>>>your coax run in your TJ is not going to help your transmit range. Just
>>>>make sure you don't leave a coil of coax somewhere.
>>>>
>>>>TW wrote:
>>>>
>>>>
>>>>>I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
>>>>>will be spent installing it.
>>>>>
>>>>>I was thinking how would it look if I could somehow install the CB antenna
>>>>>on the exact opposite side of the radio antenna (same height and spot). My
>>>>>radio antenna is on the right side of the TJ, CB antenna on the left side
>>>>>would ensure coax is shortest and the antenna would be somewhat in the
>>>>>middle of the truck (though to one side). Any ideas or photos of such an
>>>>>install?
>>>>>
>>>>>Thanks for all the help guys. Its much appreciated.
>
>
What you describe is absolutely correct by my experience.
The real trick is to get the antenna to match the xmtrs' rated load
Typically 50 ohms unbalanced.
Howard Eisenhauer wrote:
> Mike, I hope I didn't come across the wrong way on this, I have no
> desire to start a flame war over this. You have, IMHO, a well
> deserved reputation on this group for knowing your stuff, but I still
> think you're wrong.
>
> My position on this comes from being an electronics technician
> working in the radio field for somewheres on the upper side of 30
> years. An awful lot of that time has been spent testing &
> troubleshooting antenna & transmission lines on everything from
> microwave relay links to CBs, with a bunch of cell tower & military
> stuff in between. I think by now I'm pretty well grounded in both the
> theory & the practice.
>
> As far as CBs are concerned, if your antenna is properly designed &
> installed then the length of the coax line & whether or not the coax
> is coiled up is immaterial to the operation of the system. If there's
> a problem with the installation then you may well have problems with
> the coax radiating the reflected power that was supposed to go out the
> antenna. You may also experience the signal trying to get to ground
> through you power cabling instead of the coax shield. In this case
> you may well have interferance problems inside the vehicle & changing
> the length of the coax may affect your SWR meter's reading, but
> changing the length to make the meter read "right" is really only
> covering up the problem. The best way to check the SWR is with the
> meter inserted into the line right at the antenna, unfortunately the
> way most antennas are built makes this difficult. To get the real
> picture of whats happening from the radio end of the line requires an
> antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
> did I mention "$$$"?).
>
> I saw what you said about the problems you were having with your fleet
> vehicles & the data systems, I've seen it too. When the digital
> "TDMA" vehicle mount cell phones came out, we really had to crack down
> on the installers to get the VSWR down as far as possible, otherwise
> the bit error rate went crazy. We also made them trim the coax to
> "just long enough" in order to eliminate the loss from the extra
> length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
>
> If your SWR is high & you can't do anything about the antenna then you
> can reduce to problems inside the vehicle by (gasp) looping the coax a
> few times at the antenna to form an rf choke, this prevents the
> reflected signal from travelling back down the outside of the coax.
> Another trick that works is to get one of those ferrite sleeves that
> you see showing up on power & telephone cables these days. Stick it
> over the coax at the base of the antenna & it'll do the same thing as
> the loops. Running the power leads through one of these things
> wouldn't hurt either.
>
> Tell ya what- next time you're in Halifax drop me a note, I'll get
> some test equipment togeather & I'll try to show to prove to you in
> person what I'm saying is right. If I'm wrong I'll buy you a 24, If
> I'm right you do the buying, How's that?
>
> -Howard.
>
> p.s.- I drink Keith's :).
>
>
> On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
> wrote:
>
>
>>You are mistaken.
>>
>>The coil can act as a pickup for noise and it can put out RF.
>>
>>You should really read the TSB out on how to install a transmitter into
>>a new modern vehicle or you will void your vehicle warranty.
>>
>>The antenna cable can and will interfere with the vehicle's onboard
>>electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
>>Jeep automatic tranny module so every time you key up you go into
>>neutral. It also will interfere with the fuel injectors.
>>
>>GM, Chrysler and all the rest have booklets out now on how to properly
>>wire a transmitter in order to avoid voiding the vehicle warranty.
>>
>>GM insists on minimum 10 ga. power and ground run right to the battery
>>and double fused there on the opposite side of the vehicle from the
>>wiring harness. The antenna must run on the opposite side from the
>>harness too.
>>
>>So for the power lines, to have a CB on the center or passenger side of
>>a GM van, the wires have to run up the passenger side fender to the
>>front of the vehicle, across the front of the radiator supports and back
>>to the battery. If you run them across the firewall, you void the
>>warranty for the vehicle's electronics, all of them.
>>
>>Mike
>>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>>88 Cherokee 235 BFG AT's
>>
>>Howard Eisenhauer wrote:
>>
>>>TW, another old wive's tale about the coiled coax thing. If
>>>everything is working the way it should all the signal travels through
>>>the coax between the center conductor & the inside of the braid, not
>>>along the outside where coiling it would have any effect. Coiling it,
>>>tying it up or crocheting it for that matter will not make any
>>>differencet :). There are actually some situations where coiling it
>>>up would make a system work better, but you won't run into them in a
>>>jeep using a commercially available antenna.
>>>
>>>Howard.
>>>
>>>On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
>>><thomas@OBVIOUSrubicons.com> wrote:
>>>
>>>
>>>>The rule of thumb is to be 3 ft. from any other antennas. Shortening
>>>>your coax run in your TJ is not going to help your transmit range. Just
>>>>make sure you don't leave a coil of coax somewhere.
>>>>
>>>>TW wrote:
>>>>
>>>>
>>>>>I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
>>>>>will be spent installing it.
>>>>>
>>>>>I was thinking how would it look if I could somehow install the CB antenna
>>>>>on the exact opposite side of the radio antenna (same height and spot). My
>>>>>radio antenna is on the right side of the TJ, CB antenna on the left side
>>>>>would ensure coax is shortest and the antenna would be somewhat in the
>>>>>middle of the truck (though to one side). Any ideas or photos of such an
>>>>>install?
>>>>>
>>>>>Thanks for all the help guys. Its much appreciated.
>
>
Guest
Posts: n/a
Re: CB Radio or PRS - Update -(long & semi OT)
I concur!
What you describe is absolutely correct by my experience.
The real trick is to get the antenna to match the xmtrs' rated load
Typically 50 ohms unbalanced.
Howard Eisenhauer wrote:
> Mike, I hope I didn't come across the wrong way on this, I have no
> desire to start a flame war over this. You have, IMHO, a well
> deserved reputation on this group for knowing your stuff, but I still
> think you're wrong.
>
> My position on this comes from being an electronics technician
> working in the radio field for somewheres on the upper side of 30
> years. An awful lot of that time has been spent testing &
> troubleshooting antenna & transmission lines on everything from
> microwave relay links to CBs, with a bunch of cell tower & military
> stuff in between. I think by now I'm pretty well grounded in both the
> theory & the practice.
>
> As far as CBs are concerned, if your antenna is properly designed &
> installed then the length of the coax line & whether or not the coax
> is coiled up is immaterial to the operation of the system. If there's
> a problem with the installation then you may well have problems with
> the coax radiating the reflected power that was supposed to go out the
> antenna. You may also experience the signal trying to get to ground
> through you power cabling instead of the coax shield. In this case
> you may well have interferance problems inside the vehicle & changing
> the length of the coax may affect your SWR meter's reading, but
> changing the length to make the meter read "right" is really only
> covering up the problem. The best way to check the SWR is with the
> meter inserted into the line right at the antenna, unfortunately the
> way most antennas are built makes this difficult. To get the real
> picture of whats happening from the radio end of the line requires an
> antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
> did I mention "$$$"?).
>
> I saw what you said about the problems you were having with your fleet
> vehicles & the data systems, I've seen it too. When the digital
> "TDMA" vehicle mount cell phones came out, we really had to crack down
> on the installers to get the VSWR down as far as possible, otherwise
> the bit error rate went crazy. We also made them trim the coax to
> "just long enough" in order to eliminate the loss from the extra
> length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
>
> If your SWR is high & you can't do anything about the antenna then you
> can reduce to problems inside the vehicle by (gasp) looping the coax a
> few times at the antenna to form an rf choke, this prevents the
> reflected signal from travelling back down the outside of the coax.
> Another trick that works is to get one of those ferrite sleeves that
> you see showing up on power & telephone cables these days. Stick it
> over the coax at the base of the antenna & it'll do the same thing as
> the loops. Running the power leads through one of these things
> wouldn't hurt either.
>
> Tell ya what- next time you're in Halifax drop me a note, I'll get
> some test equipment togeather & I'll try to show to prove to you in
> person what I'm saying is right. If I'm wrong I'll buy you a 24, If
> I'm right you do the buying, How's that?
>
> -Howard.
>
> p.s.- I drink Keith's :).
>
>
> On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
> wrote:
>
>
>>You are mistaken.
>>
>>The coil can act as a pickup for noise and it can put out RF.
>>
>>You should really read the TSB out on how to install a transmitter into
>>a new modern vehicle or you will void your vehicle warranty.
>>
>>The antenna cable can and will interfere with the vehicle's onboard
>>electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
>>Jeep automatic tranny module so every time you key up you go into
>>neutral. It also will interfere with the fuel injectors.
>>
>>GM, Chrysler and all the rest have booklets out now on how to properly
>>wire a transmitter in order to avoid voiding the vehicle warranty.
>>
>>GM insists on minimum 10 ga. power and ground run right to the battery
>>and double fused there on the opposite side of the vehicle from the
>>wiring harness. The antenna must run on the opposite side from the
>>harness too.
>>
>>So for the power lines, to have a CB on the center or passenger side of
>>a GM van, the wires have to run up the passenger side fender to the
>>front of the vehicle, across the front of the radiator supports and back
>>to the battery. If you run them across the firewall, you void the
>>warranty for the vehicle's electronics, all of them.
>>
>>Mike
>>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>>88 Cherokee 235 BFG AT's
>>
>>Howard Eisenhauer wrote:
>>
>>>TW, another old wive's tale about the coiled coax thing. If
>>>everything is working the way it should all the signal travels through
>>>the coax between the center conductor & the inside of the braid, not
>>>along the outside where coiling it would have any effect. Coiling it,
>>>tying it up or crocheting it for that matter will not make any
>>>differencet :). There are actually some situations where coiling it
>>>up would make a system work better, but you won't run into them in a
>>>jeep using a commercially available antenna.
>>>
>>>Howard.
>>>
>>>On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
>>><thomas@OBVIOUSrubicons.com> wrote:
>>>
>>>
>>>>The rule of thumb is to be 3 ft. from any other antennas. Shortening
>>>>your coax run in your TJ is not going to help your transmit range. Just
>>>>make sure you don't leave a coil of coax somewhere.
>>>>
>>>>TW wrote:
>>>>
>>>>
>>>>>I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
>>>>>will be spent installing it.
>>>>>
>>>>>I was thinking how would it look if I could somehow install the CB antenna
>>>>>on the exact opposite side of the radio antenna (same height and spot). My
>>>>>radio antenna is on the right side of the TJ, CB antenna on the left side
>>>>>would ensure coax is shortest and the antenna would be somewhat in the
>>>>>middle of the truck (though to one side). Any ideas or photos of such an
>>>>>install?
>>>>>
>>>>>Thanks for all the help guys. Its much appreciated.
>
>
What you describe is absolutely correct by my experience.
The real trick is to get the antenna to match the xmtrs' rated load
Typically 50 ohms unbalanced.
Howard Eisenhauer wrote:
> Mike, I hope I didn't come across the wrong way on this, I have no
> desire to start a flame war over this. You have, IMHO, a well
> deserved reputation on this group for knowing your stuff, but I still
> think you're wrong.
>
> My position on this comes from being an electronics technician
> working in the radio field for somewheres on the upper side of 30
> years. An awful lot of that time has been spent testing &
> troubleshooting antenna & transmission lines on everything from
> microwave relay links to CBs, with a bunch of cell tower & military
> stuff in between. I think by now I'm pretty well grounded in both the
> theory & the practice.
>
> As far as CBs are concerned, if your antenna is properly designed &
> installed then the length of the coax line & whether or not the coax
> is coiled up is immaterial to the operation of the system. If there's
> a problem with the installation then you may well have problems with
> the coax radiating the reflected power that was supposed to go out the
> antenna. You may also experience the signal trying to get to ground
> through you power cabling instead of the coax shield. In this case
> you may well have interferance problems inside the vehicle & changing
> the length of the coax may affect your SWR meter's reading, but
> changing the length to make the meter read "right" is really only
> covering up the problem. The best way to check the SWR is with the
> meter inserted into the line right at the antenna, unfortunately the
> way most antennas are built makes this difficult. To get the real
> picture of whats happening from the radio end of the line requires an
> antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
> did I mention "$$$"?).
>
> I saw what you said about the problems you were having with your fleet
> vehicles & the data systems, I've seen it too. When the digital
> "TDMA" vehicle mount cell phones came out, we really had to crack down
> on the installers to get the VSWR down as far as possible, otherwise
> the bit error rate went crazy. We also made them trim the coax to
> "just long enough" in order to eliminate the loss from the extra
> length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
>
> If your SWR is high & you can't do anything about the antenna then you
> can reduce to problems inside the vehicle by (gasp) looping the coax a
> few times at the antenna to form an rf choke, this prevents the
> reflected signal from travelling back down the outside of the coax.
> Another trick that works is to get one of those ferrite sleeves that
> you see showing up on power & telephone cables these days. Stick it
> over the coax at the base of the antenna & it'll do the same thing as
> the loops. Running the power leads through one of these things
> wouldn't hurt either.
>
> Tell ya what- next time you're in Halifax drop me a note, I'll get
> some test equipment togeather & I'll try to show to prove to you in
> person what I'm saying is right. If I'm wrong I'll buy you a 24, If
> I'm right you do the buying, How's that?
>
> -Howard.
>
> p.s.- I drink Keith's :).
>
>
> On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
> wrote:
>
>
>>You are mistaken.
>>
>>The coil can act as a pickup for noise and it can put out RF.
>>
>>You should really read the TSB out on how to install a transmitter into
>>a new modern vehicle or you will void your vehicle warranty.
>>
>>The antenna cable can and will interfere with the vehicle's onboard
>>electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
>>Jeep automatic tranny module so every time you key up you go into
>>neutral. It also will interfere with the fuel injectors.
>>
>>GM, Chrysler and all the rest have booklets out now on how to properly
>>wire a transmitter in order to avoid voiding the vehicle warranty.
>>
>>GM insists on minimum 10 ga. power and ground run right to the battery
>>and double fused there on the opposite side of the vehicle from the
>>wiring harness. The antenna must run on the opposite side from the
>>harness too.
>>
>>So for the power lines, to have a CB on the center or passenger side of
>>a GM van, the wires have to run up the passenger side fender to the
>>front of the vehicle, across the front of the radiator supports and back
>>to the battery. If you run them across the firewall, you void the
>>warranty for the vehicle's electronics, all of them.
>>
>>Mike
>>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>>88 Cherokee 235 BFG AT's
>>
>>Howard Eisenhauer wrote:
>>
>>>TW, another old wive's tale about the coiled coax thing. If
>>>everything is working the way it should all the signal travels through
>>>the coax between the center conductor & the inside of the braid, not
>>>along the outside where coiling it would have any effect. Coiling it,
>>>tying it up or crocheting it for that matter will not make any
>>>differencet :). There are actually some situations where coiling it
>>>up would make a system work better, but you won't run into them in a
>>>jeep using a commercially available antenna.
>>>
>>>Howard.
>>>
>>>On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
>>><thomas@OBVIOUSrubicons.com> wrote:
>>>
>>>
>>>>The rule of thumb is to be 3 ft. from any other antennas. Shortening
>>>>your coax run in your TJ is not going to help your transmit range. Just
>>>>make sure you don't leave a coil of coax somewhere.
>>>>
>>>>TW wrote:
>>>>
>>>>
>>>>>I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
>>>>>will be spent installing it.
>>>>>
>>>>>I was thinking how would it look if I could somehow install the CB antenna
>>>>>on the exact opposite side of the radio antenna (same height and spot). My
>>>>>radio antenna is on the right side of the TJ, CB antenna on the left side
>>>>>would ensure coax is shortest and the antenna would be somewhat in the
>>>>>middle of the truck (though to one side). Any ideas or photos of such an
>>>>>install?
>>>>>
>>>>>Thanks for all the help guys. Its much appreciated.
>
>
Guest
Posts: n/a
Re: CB Radio or PRS - Update -(long & semi OT)
I concur!
What you describe is absolutely correct by my experience.
The real trick is to get the antenna to match the xmtrs' rated load
Typically 50 ohms unbalanced.
Howard Eisenhauer wrote:
> Mike, I hope I didn't come across the wrong way on this, I have no
> desire to start a flame war over this. You have, IMHO, a well
> deserved reputation on this group for knowing your stuff, but I still
> think you're wrong.
>
> My position on this comes from being an electronics technician
> working in the radio field for somewheres on the upper side of 30
> years. An awful lot of that time has been spent testing &
> troubleshooting antenna & transmission lines on everything from
> microwave relay links to CBs, with a bunch of cell tower & military
> stuff in between. I think by now I'm pretty well grounded in both the
> theory & the practice.
>
> As far as CBs are concerned, if your antenna is properly designed &
> installed then the length of the coax line & whether or not the coax
> is coiled up is immaterial to the operation of the system. If there's
> a problem with the installation then you may well have problems with
> the coax radiating the reflected power that was supposed to go out the
> antenna. You may also experience the signal trying to get to ground
> through you power cabling instead of the coax shield. In this case
> you may well have interferance problems inside the vehicle & changing
> the length of the coax may affect your SWR meter's reading, but
> changing the length to make the meter read "right" is really only
> covering up the problem. The best way to check the SWR is with the
> meter inserted into the line right at the antenna, unfortunately the
> way most antennas are built makes this difficult. To get the real
> picture of whats happening from the radio end of the line requires an
> antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
> did I mention "$$$"?).
>
> I saw what you said about the problems you were having with your fleet
> vehicles & the data systems, I've seen it too. When the digital
> "TDMA" vehicle mount cell phones came out, we really had to crack down
> on the installers to get the VSWR down as far as possible, otherwise
> the bit error rate went crazy. We also made them trim the coax to
> "just long enough" in order to eliminate the loss from the extra
> length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
>
> If your SWR is high & you can't do anything about the antenna then you
> can reduce to problems inside the vehicle by (gasp) looping the coax a
> few times at the antenna to form an rf choke, this prevents the
> reflected signal from travelling back down the outside of the coax.
> Another trick that works is to get one of those ferrite sleeves that
> you see showing up on power & telephone cables these days. Stick it
> over the coax at the base of the antenna & it'll do the same thing as
> the loops. Running the power leads through one of these things
> wouldn't hurt either.
>
> Tell ya what- next time you're in Halifax drop me a note, I'll get
> some test equipment togeather & I'll try to show to prove to you in
> person what I'm saying is right. If I'm wrong I'll buy you a 24, If
> I'm right you do the buying, How's that?
>
> -Howard.
>
> p.s.- I drink Keith's :).
>
>
> On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
> wrote:
>
>
>>You are mistaken.
>>
>>The coil can act as a pickup for noise and it can put out RF.
>>
>>You should really read the TSB out on how to install a transmitter into
>>a new modern vehicle or you will void your vehicle warranty.
>>
>>The antenna cable can and will interfere with the vehicle's onboard
>>electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
>>Jeep automatic tranny module so every time you key up you go into
>>neutral. It also will interfere with the fuel injectors.
>>
>>GM, Chrysler and all the rest have booklets out now on how to properly
>>wire a transmitter in order to avoid voiding the vehicle warranty.
>>
>>GM insists on minimum 10 ga. power and ground run right to the battery
>>and double fused there on the opposite side of the vehicle from the
>>wiring harness. The antenna must run on the opposite side from the
>>harness too.
>>
>>So for the power lines, to have a CB on the center or passenger side of
>>a GM van, the wires have to run up the passenger side fender to the
>>front of the vehicle, across the front of the radiator supports and back
>>to the battery. If you run them across the firewall, you void the
>>warranty for the vehicle's electronics, all of them.
>>
>>Mike
>>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>>88 Cherokee 235 BFG AT's
>>
>>Howard Eisenhauer wrote:
>>
>>>TW, another old wive's tale about the coiled coax thing. If
>>>everything is working the way it should all the signal travels through
>>>the coax between the center conductor & the inside of the braid, not
>>>along the outside where coiling it would have any effect. Coiling it,
>>>tying it up or crocheting it for that matter will not make any
>>>differencet :). There are actually some situations where coiling it
>>>up would make a system work better, but you won't run into them in a
>>>jeep using a commercially available antenna.
>>>
>>>Howard.
>>>
>>>On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
>>><thomas@OBVIOUSrubicons.com> wrote:
>>>
>>>
>>>>The rule of thumb is to be 3 ft. from any other antennas. Shortening
>>>>your coax run in your TJ is not going to help your transmit range. Just
>>>>make sure you don't leave a coil of coax somewhere.
>>>>
>>>>TW wrote:
>>>>
>>>>
>>>>>I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
>>>>>will be spent installing it.
>>>>>
>>>>>I was thinking how would it look if I could somehow install the CB antenna
>>>>>on the exact opposite side of the radio antenna (same height and spot). My
>>>>>radio antenna is on the right side of the TJ, CB antenna on the left side
>>>>>would ensure coax is shortest and the antenna would be somewhat in the
>>>>>middle of the truck (though to one side). Any ideas or photos of such an
>>>>>install?
>>>>>
>>>>>Thanks for all the help guys. Its much appreciated.
>
>
What you describe is absolutely correct by my experience.
The real trick is to get the antenna to match the xmtrs' rated load
Typically 50 ohms unbalanced.
Howard Eisenhauer wrote:
> Mike, I hope I didn't come across the wrong way on this, I have no
> desire to start a flame war over this. You have, IMHO, a well
> deserved reputation on this group for knowing your stuff, but I still
> think you're wrong.
>
> My position on this comes from being an electronics technician
> working in the radio field for somewheres on the upper side of 30
> years. An awful lot of that time has been spent testing &
> troubleshooting antenna & transmission lines on everything from
> microwave relay links to CBs, with a bunch of cell tower & military
> stuff in between. I think by now I'm pretty well grounded in both the
> theory & the practice.
>
> As far as CBs are concerned, if your antenna is properly designed &
> installed then the length of the coax line & whether or not the coax
> is coiled up is immaterial to the operation of the system. If there's
> a problem with the installation then you may well have problems with
> the coax radiating the reflected power that was supposed to go out the
> antenna. You may also experience the signal trying to get to ground
> through you power cabling instead of the coax shield. In this case
> you may well have interferance problems inside the vehicle & changing
> the length of the coax may affect your SWR meter's reading, but
> changing the length to make the meter read "right" is really only
> covering up the problem. The best way to check the SWR is with the
> meter inserted into the line right at the antenna, unfortunately the
> way most antennas are built makes this difficult. To get the real
> picture of whats happening from the radio end of the line requires an
> antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
> did I mention "$$$"?).
>
> I saw what you said about the problems you were having with your fleet
> vehicles & the data systems, I've seen it too. When the digital
> "TDMA" vehicle mount cell phones came out, we really had to crack down
> on the installers to get the VSWR down as far as possible, otherwise
> the bit error rate went crazy. We also made them trim the coax to
> "just long enough" in order to eliminate the loss from the extra
> length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
>
> If your SWR is high & you can't do anything about the antenna then you
> can reduce to problems inside the vehicle by (gasp) looping the coax a
> few times at the antenna to form an rf choke, this prevents the
> reflected signal from travelling back down the outside of the coax.
> Another trick that works is to get one of those ferrite sleeves that
> you see showing up on power & telephone cables these days. Stick it
> over the coax at the base of the antenna & it'll do the same thing as
> the loops. Running the power leads through one of these things
> wouldn't hurt either.
>
> Tell ya what- next time you're in Halifax drop me a note, I'll get
> some test equipment togeather & I'll try to show to prove to you in
> person what I'm saying is right. If I'm wrong I'll buy you a 24, If
> I'm right you do the buying, How's that?
>
> -Howard.
>
> p.s.- I drink Keith's :).
>
>
> On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
> wrote:
>
>
>>You are mistaken.
>>
>>The coil can act as a pickup for noise and it can put out RF.
>>
>>You should really read the TSB out on how to install a transmitter into
>>a new modern vehicle or you will void your vehicle warranty.
>>
>>The antenna cable can and will interfere with the vehicle's onboard
>>electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
>>Jeep automatic tranny module so every time you key up you go into
>>neutral. It also will interfere with the fuel injectors.
>>
>>GM, Chrysler and all the rest have booklets out now on how to properly
>>wire a transmitter in order to avoid voiding the vehicle warranty.
>>
>>GM insists on minimum 10 ga. power and ground run right to the battery
>>and double fused there on the opposite side of the vehicle from the
>>wiring harness. The antenna must run on the opposite side from the
>>harness too.
>>
>>So for the power lines, to have a CB on the center or passenger side of
>>a GM van, the wires have to run up the passenger side fender to the
>>front of the vehicle, across the front of the radiator supports and back
>>to the battery. If you run them across the firewall, you void the
>>warranty for the vehicle's electronics, all of them.
>>
>>Mike
>>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>>88 Cherokee 235 BFG AT's
>>
>>Howard Eisenhauer wrote:
>>
>>>TW, another old wive's tale about the coiled coax thing. If
>>>everything is working the way it should all the signal travels through
>>>the coax between the center conductor & the inside of the braid, not
>>>along the outside where coiling it would have any effect. Coiling it,
>>>tying it up or crocheting it for that matter will not make any
>>>differencet :). There are actually some situations where coiling it
>>>up would make a system work better, but you won't run into them in a
>>>jeep using a commercially available antenna.
>>>
>>>Howard.
>>>
>>>On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
>>><thomas@OBVIOUSrubicons.com> wrote:
>>>
>>>
>>>>The rule of thumb is to be 3 ft. from any other antennas. Shortening
>>>>your coax run in your TJ is not going to help your transmit range. Just
>>>>make sure you don't leave a coil of coax somewhere.
>>>>
>>>>TW wrote:
>>>>
>>>>
>>>>>I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
>>>>>will be spent installing it.
>>>>>
>>>>>I was thinking how would it look if I could somehow install the CB antenna
>>>>>on the exact opposite side of the radio antenna (same height and spot). My
>>>>>radio antenna is on the right side of the TJ, CB antenna on the left side
>>>>>would ensure coax is shortest and the antenna would be somewhat in the
>>>>>middle of the truck (though to one side). Any ideas or photos of such an
>>>>>install?
>>>>>
>>>>>Thanks for all the help guys. Its much appreciated.
>
>
Guest
Posts: n/a
Re: CB Radio or PRS - Update -(long & semi OT)
I concur!
What you describe is absolutely correct by my experience.
The real trick is to get the antenna to match the xmtrs' rated load
Typically 50 ohms unbalanced.
Howard Eisenhauer wrote:
> Mike, I hope I didn't come across the wrong way on this, I have no
> desire to start a flame war over this. You have, IMHO, a well
> deserved reputation on this group for knowing your stuff, but I still
> think you're wrong.
>
> My position on this comes from being an electronics technician
> working in the radio field for somewheres on the upper side of 30
> years. An awful lot of that time has been spent testing &
> troubleshooting antenna & transmission lines on everything from
> microwave relay links to CBs, with a bunch of cell tower & military
> stuff in between. I think by now I'm pretty well grounded in both the
> theory & the practice.
>
> As far as CBs are concerned, if your antenna is properly designed &
> installed then the length of the coax line & whether or not the coax
> is coiled up is immaterial to the operation of the system. If there's
> a problem with the installation then you may well have problems with
> the coax radiating the reflected power that was supposed to go out the
> antenna. You may also experience the signal trying to get to ground
> through you power cabling instead of the coax shield. In this case
> you may well have interferance problems inside the vehicle & changing
> the length of the coax may affect your SWR meter's reading, but
> changing the length to make the meter read "right" is really only
> covering up the problem. The best way to check the SWR is with the
> meter inserted into the line right at the antenna, unfortunately the
> way most antennas are built makes this difficult. To get the real
> picture of whats happening from the radio end of the line requires an
> antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
> did I mention "$$$"?).
>
> I saw what you said about the problems you were having with your fleet
> vehicles & the data systems, I've seen it too. When the digital
> "TDMA" vehicle mount cell phones came out, we really had to crack down
> on the installers to get the VSWR down as far as possible, otherwise
> the bit error rate went crazy. We also made them trim the coax to
> "just long enough" in order to eliminate the loss from the extra
> length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
>
> If your SWR is high & you can't do anything about the antenna then you
> can reduce to problems inside the vehicle by (gasp) looping the coax a
> few times at the antenna to form an rf choke, this prevents the
> reflected signal from travelling back down the outside of the coax.
> Another trick that works is to get one of those ferrite sleeves that
> you see showing up on power & telephone cables these days. Stick it
> over the coax at the base of the antenna & it'll do the same thing as
> the loops. Running the power leads through one of these things
> wouldn't hurt either.
>
> Tell ya what- next time you're in Halifax drop me a note, I'll get
> some test equipment togeather & I'll try to show to prove to you in
> person what I'm saying is right. If I'm wrong I'll buy you a 24, If
> I'm right you do the buying, How's that?
>
> -Howard.
>
> p.s.- I drink Keith's :).
>
>
> On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
> wrote:
>
>
>>You are mistaken.
>>
>>The coil can act as a pickup for noise and it can put out RF.
>>
>>You should really read the TSB out on how to install a transmitter into
>>a new modern vehicle or you will void your vehicle warranty.
>>
>>The antenna cable can and will interfere with the vehicle's onboard
>>electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
>>Jeep automatic tranny module so every time you key up you go into
>>neutral. It also will interfere with the fuel injectors.
>>
>>GM, Chrysler and all the rest have booklets out now on how to properly
>>wire a transmitter in order to avoid voiding the vehicle warranty.
>>
>>GM insists on minimum 10 ga. power and ground run right to the battery
>>and double fused there on the opposite side of the vehicle from the
>>wiring harness. The antenna must run on the opposite side from the
>>harness too.
>>
>>So for the power lines, to have a CB on the center or passenger side of
>>a GM van, the wires have to run up the passenger side fender to the
>>front of the vehicle, across the front of the radiator supports and back
>>to the battery. If you run them across the firewall, you void the
>>warranty for the vehicle's electronics, all of them.
>>
>>Mike
>>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>>88 Cherokee 235 BFG AT's
>>
>>Howard Eisenhauer wrote:
>>
>>>TW, another old wive's tale about the coiled coax thing. If
>>>everything is working the way it should all the signal travels through
>>>the coax between the center conductor & the inside of the braid, not
>>>along the outside where coiling it would have any effect. Coiling it,
>>>tying it up or crocheting it for that matter will not make any
>>>differencet :). There are actually some situations where coiling it
>>>up would make a system work better, but you won't run into them in a
>>>jeep using a commercially available antenna.
>>>
>>>Howard.
>>>
>>>On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
>>><thomas@OBVIOUSrubicons.com> wrote:
>>>
>>>
>>>>The rule of thumb is to be 3 ft. from any other antennas. Shortening
>>>>your coax run in your TJ is not going to help your transmit range. Just
>>>>make sure you don't leave a coil of coax somewhere.
>>>>
>>>>TW wrote:
>>>>
>>>>
>>>>>I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
>>>>>will be spent installing it.
>>>>>
>>>>>I was thinking how would it look if I could somehow install the CB antenna
>>>>>on the exact opposite side of the radio antenna (same height and spot). My
>>>>>radio antenna is on the right side of the TJ, CB antenna on the left side
>>>>>would ensure coax is shortest and the antenna would be somewhat in the
>>>>>middle of the truck (though to one side). Any ideas or photos of such an
>>>>>install?
>>>>>
>>>>>Thanks for all the help guys. Its much appreciated.
>
>
What you describe is absolutely correct by my experience.
The real trick is to get the antenna to match the xmtrs' rated load
Typically 50 ohms unbalanced.
Howard Eisenhauer wrote:
> Mike, I hope I didn't come across the wrong way on this, I have no
> desire to start a flame war over this. You have, IMHO, a well
> deserved reputation on this group for knowing your stuff, but I still
> think you're wrong.
>
> My position on this comes from being an electronics technician
> working in the radio field for somewheres on the upper side of 30
> years. An awful lot of that time has been spent testing &
> troubleshooting antenna & transmission lines on everything from
> microwave relay links to CBs, with a bunch of cell tower & military
> stuff in between. I think by now I'm pretty well grounded in both the
> theory & the practice.
>
> As far as CBs are concerned, if your antenna is properly designed &
> installed then the length of the coax line & whether or not the coax
> is coiled up is immaterial to the operation of the system. If there's
> a problem with the installation then you may well have problems with
> the coax radiating the reflected power that was supposed to go out the
> antenna. You may also experience the signal trying to get to ground
> through you power cabling instead of the coax shield. In this case
> you may well have interferance problems inside the vehicle & changing
> the length of the coax may affect your SWR meter's reading, but
> changing the length to make the meter read "right" is really only
> covering up the problem. The best way to check the SWR is with the
> meter inserted into the line right at the antenna, unfortunately the
> way most antennas are built makes this difficult. To get the real
> picture of whats happening from the radio end of the line requires an
> antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
> did I mention "$$$"?).
>
> I saw what you said about the problems you were having with your fleet
> vehicles & the data systems, I've seen it too. When the digital
> "TDMA" vehicle mount cell phones came out, we really had to crack down
> on the installers to get the VSWR down as far as possible, otherwise
> the bit error rate went crazy. We also made them trim the coax to
> "just long enough" in order to eliminate the loss from the extra
> length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
>
> If your SWR is high & you can't do anything about the antenna then you
> can reduce to problems inside the vehicle by (gasp) looping the coax a
> few times at the antenna to form an rf choke, this prevents the
> reflected signal from travelling back down the outside of the coax.
> Another trick that works is to get one of those ferrite sleeves that
> you see showing up on power & telephone cables these days. Stick it
> over the coax at the base of the antenna & it'll do the same thing as
> the loops. Running the power leads through one of these things
> wouldn't hurt either.
>
> Tell ya what- next time you're in Halifax drop me a note, I'll get
> some test equipment togeather & I'll try to show to prove to you in
> person what I'm saying is right. If I'm wrong I'll buy you a 24, If
> I'm right you do the buying, How's that?
>
> -Howard.
>
> p.s.- I drink Keith's :).
>
>
> On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
> wrote:
>
>
>>You are mistaken.
>>
>>The coil can act as a pickup for noise and it can put out RF.
>>
>>You should really read the TSB out on how to install a transmitter into
>>a new modern vehicle or you will void your vehicle warranty.
>>
>>The antenna cable can and will interfere with the vehicle's onboard
>>electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
>>Jeep automatic tranny module so every time you key up you go into
>>neutral. It also will interfere with the fuel injectors.
>>
>>GM, Chrysler and all the rest have booklets out now on how to properly
>>wire a transmitter in order to avoid voiding the vehicle warranty.
>>
>>GM insists on minimum 10 ga. power and ground run right to the battery
>>and double fused there on the opposite side of the vehicle from the
>>wiring harness. The antenna must run on the opposite side from the
>>harness too.
>>
>>So for the power lines, to have a CB on the center or passenger side of
>>a GM van, the wires have to run up the passenger side fender to the
>>front of the vehicle, across the front of the radiator supports and back
>>to the battery. If you run them across the firewall, you void the
>>warranty for the vehicle's electronics, all of them.
>>
>>Mike
>>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>>88 Cherokee 235 BFG AT's
>>
>>Howard Eisenhauer wrote:
>>
>>>TW, another old wive's tale about the coiled coax thing. If
>>>everything is working the way it should all the signal travels through
>>>the coax between the center conductor & the inside of the braid, not
>>>along the outside where coiling it would have any effect. Coiling it,
>>>tying it up or crocheting it for that matter will not make any
>>>differencet :). There are actually some situations where coiling it
>>>up would make a system work better, but you won't run into them in a
>>>jeep using a commercially available antenna.
>>>
>>>Howard.
>>>
>>>On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
>>><thomas@OBVIOUSrubicons.com> wrote:
>>>
>>>
>>>>The rule of thumb is to be 3 ft. from any other antennas. Shortening
>>>>your coax run in your TJ is not going to help your transmit range. Just
>>>>make sure you don't leave a coil of coax somewhere.
>>>>
>>>>TW wrote:
>>>>
>>>>
>>>>>I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
>>>>>will be spent installing it.
>>>>>
>>>>>I was thinking how would it look if I could somehow install the CB antenna
>>>>>on the exact opposite side of the radio antenna (same height and spot). My
>>>>>radio antenna is on the right side of the TJ, CB antenna on the left side
>>>>>would ensure coax is shortest and the antenna would be somewhat in the
>>>>>middle of the truck (though to one side). Any ideas or photos of such an
>>>>>install?
>>>>>
>>>>>Thanks for all the help guys. Its much appreciated.
>
>
Guest
Posts: n/a
Re: CB Radio or PRS - Update -(long & semi OT)
Well, never could turn down a Keith's! Even if I do end up buying. ;-)
I can see what you are saying, if done right no issues.
I guess I just see a lot of crappie installs that 'do' interfere with
onboard systems and am used to the 900 mhz stuff.
I also have a big ball of antenna cable stuck in-between the fiberglass
body layers I wouldn't mind getting rid of.
Mike
Howard Eisenhauer wrote:
>
> Mike, I hope I didn't come across the wrong way on this, I have no
> desire to start a flame war over this. You have, IMHO, a well
> deserved reputation on this group for knowing your stuff, but I still
> think you're wrong.
>
> My position on this comes from being an electronics technician
> working in the radio field for somewheres on the upper side of 30
> years. An awful lot of that time has been spent testing &
> troubleshooting antenna & transmission lines on everything from
> microwave relay links to CBs, with a bunch of cell tower & military
> stuff in between. I think by now I'm pretty well grounded in both the
> theory & the practice.
>
> As far as CBs are concerned, if your antenna is properly designed &
> installed then the length of the coax line & whether or not the coax
> is coiled up is immaterial to the operation of the system. If there's
> a problem with the installation then you may well have problems with
> the coax radiating the reflected power that was supposed to go out the
> antenna. You may also experience the signal trying to get to ground
> through you power cabling instead of the coax shield. In this case
> you may well have interferance problems inside the vehicle & changing
> the length of the coax may affect your SWR meter's reading, but
> changing the length to make the meter read "right" is really only
> covering up the problem. The best way to check the SWR is with the
> meter inserted into the line right at the antenna, unfortunately the
> way most antennas are built makes this difficult. To get the real
> picture of whats happening from the radio end of the line requires an
> antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
> did I mention "$$$"?).
>
> I saw what you said about the problems you were having with your fleet
> vehicles & the data systems, I've seen it too. When the digital
> "TDMA" vehicle mount cell phones came out, we really had to crack down
> on the installers to get the VSWR down as far as possible, otherwise
> the bit error rate went crazy. We also made them trim the coax to
> "just long enough" in order to eliminate the loss from the extra
> length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
>
> If your SWR is high & you can't do anything about the antenna then you
> can reduce to problems inside the vehicle by (gasp) looping the coax a
> few times at the antenna to form an rf choke, this prevents the
> reflected signal from travelling back down the outside of the coax.
> Another trick that works is to get one of those ferrite sleeves that
> you see showing up on power & telephone cables these days. Stick it
> over the coax at the base of the antenna & it'll do the same thing as
> the loops. Running the power leads through one of these things
> wouldn't hurt either.
>
> Tell ya what- next time you're in Halifax drop me a note, I'll get
> some test equipment togeather & I'll try to show to prove to you in
> person what I'm saying is right. If I'm wrong I'll buy you a 24, If
> I'm right you do the buying, How's that?
>
> -Howard.
>
> p.s.- I drink Keith's :).
>
> On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
> wrote:
>
> >You are mistaken.
> >
> >The coil can act as a pickup for noise and it can put out RF.
> >
> >You should really read the TSB out on how to install a transmitter into
> >a new modern vehicle or you will void your vehicle warranty.
> >
> >The antenna cable can and will interfere with the vehicle's onboard
> >electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
> >Jeep automatic tranny module so every time you key up you go into
> >neutral. It also will interfere with the fuel injectors.
> >
> >GM, Chrysler and all the rest have booklets out now on how to properly
> >wire a transmitter in order to avoid voiding the vehicle warranty.
> >
> >GM insists on minimum 10 ga. power and ground run right to the battery
> >and double fused there on the opposite side of the vehicle from the
> >wiring harness. The antenna must run on the opposite side from the
> >harness too.
> >
> >So for the power lines, to have a CB on the center or passenger side of
> >a GM van, the wires have to run up the passenger side fender to the
> >front of the vehicle, across the front of the radiator supports and back
> >to the battery. If you run them across the firewall, you void the
> >warranty for the vehicle's electronics, all of them.
> >
> >Mike
> >86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >88 Cherokee 235 BFG AT's
> >
> >Howard Eisenhauer wrote:
> >>
> >> TW, another old wive's tale about the coiled coax thing. If
> >> everything is working the way it should all the signal travels through
> >> the coax between the center conductor & the inside of the braid, not
> >> along the outside where coiling it would have any effect. Coiling it,
> >> tying it up or crocheting it for that matter will not make any
> >> differencet :). There are actually some situations where coiling it
> >> up would make a system work better, but you won't run into them in a
> >> jeep using a commercially available antenna.
> >>
> >> Howard.
> >>
> >> On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
> >> <thomas@OBVIOUSrubicons.com> wrote:
> >>
> >> >The rule of thumb is to be 3 ft. from any other antennas. Shortening
> >> >your coax run in your TJ is not going to help your transmit range. Just
> >> >make sure you don't leave a coil of coax somewhere.
> >> >
> >> >TW wrote:
> >> >
> >> >> I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
> >> >> will be spent installing it.
> >> >>
> >> >> I was thinking how would it look if I could somehow install the CB antenna
> >> >> on the exact opposite side of the radio antenna (same height and spot). My
> >> >> radio antenna is on the right side of the TJ, CB antenna on the left side
> >> >> would ensure coax is shortest and the antenna would be somewhat in the
> >> >> middle of the truck (though to one side). Any ideas or photos of such an
> >> >> install?
> >> >>
> >> >> Thanks for all the help guys. Its much appreciated.
I can see what you are saying, if done right no issues.
I guess I just see a lot of crappie installs that 'do' interfere with
onboard systems and am used to the 900 mhz stuff.
I also have a big ball of antenna cable stuck in-between the fiberglass
body layers I wouldn't mind getting rid of.
Mike
Howard Eisenhauer wrote:
>
> Mike, I hope I didn't come across the wrong way on this, I have no
> desire to start a flame war over this. You have, IMHO, a well
> deserved reputation on this group for knowing your stuff, but I still
> think you're wrong.
>
> My position on this comes from being an electronics technician
> working in the radio field for somewheres on the upper side of 30
> years. An awful lot of that time has been spent testing &
> troubleshooting antenna & transmission lines on everything from
> microwave relay links to CBs, with a bunch of cell tower & military
> stuff in between. I think by now I'm pretty well grounded in both the
> theory & the practice.
>
> As far as CBs are concerned, if your antenna is properly designed &
> installed then the length of the coax line & whether or not the coax
> is coiled up is immaterial to the operation of the system. If there's
> a problem with the installation then you may well have problems with
> the coax radiating the reflected power that was supposed to go out the
> antenna. You may also experience the signal trying to get to ground
> through you power cabling instead of the coax shield. In this case
> you may well have interferance problems inside the vehicle & changing
> the length of the coax may affect your SWR meter's reading, but
> changing the length to make the meter read "right" is really only
> covering up the problem. The best way to check the SWR is with the
> meter inserted into the line right at the antenna, unfortunately the
> way most antennas are built makes this difficult. To get the real
> picture of whats happening from the radio end of the line requires an
> antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
> did I mention "$$$"?).
>
> I saw what you said about the problems you were having with your fleet
> vehicles & the data systems, I've seen it too. When the digital
> "TDMA" vehicle mount cell phones came out, we really had to crack down
> on the installers to get the VSWR down as far as possible, otherwise
> the bit error rate went crazy. We also made them trim the coax to
> "just long enough" in order to eliminate the loss from the extra
> length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
>
> If your SWR is high & you can't do anything about the antenna then you
> can reduce to problems inside the vehicle by (gasp) looping the coax a
> few times at the antenna to form an rf choke, this prevents the
> reflected signal from travelling back down the outside of the coax.
> Another trick that works is to get one of those ferrite sleeves that
> you see showing up on power & telephone cables these days. Stick it
> over the coax at the base of the antenna & it'll do the same thing as
> the loops. Running the power leads through one of these things
> wouldn't hurt either.
>
> Tell ya what- next time you're in Halifax drop me a note, I'll get
> some test equipment togeather & I'll try to show to prove to you in
> person what I'm saying is right. If I'm wrong I'll buy you a 24, If
> I'm right you do the buying, How's that?
>
> -Howard.
>
> p.s.- I drink Keith's :).
>
> On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
> wrote:
>
> >You are mistaken.
> >
> >The coil can act as a pickup for noise and it can put out RF.
> >
> >You should really read the TSB out on how to install a transmitter into
> >a new modern vehicle or you will void your vehicle warranty.
> >
> >The antenna cable can and will interfere with the vehicle's onboard
> >electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
> >Jeep automatic tranny module so every time you key up you go into
> >neutral. It also will interfere with the fuel injectors.
> >
> >GM, Chrysler and all the rest have booklets out now on how to properly
> >wire a transmitter in order to avoid voiding the vehicle warranty.
> >
> >GM insists on minimum 10 ga. power and ground run right to the battery
> >and double fused there on the opposite side of the vehicle from the
> >wiring harness. The antenna must run on the opposite side from the
> >harness too.
> >
> >So for the power lines, to have a CB on the center or passenger side of
> >a GM van, the wires have to run up the passenger side fender to the
> >front of the vehicle, across the front of the radiator supports and back
> >to the battery. If you run them across the firewall, you void the
> >warranty for the vehicle's electronics, all of them.
> >
> >Mike
> >86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >88 Cherokee 235 BFG AT's
> >
> >Howard Eisenhauer wrote:
> >>
> >> TW, another old wive's tale about the coiled coax thing. If
> >> everything is working the way it should all the signal travels through
> >> the coax between the center conductor & the inside of the braid, not
> >> along the outside where coiling it would have any effect. Coiling it,
> >> tying it up or crocheting it for that matter will not make any
> >> differencet :). There are actually some situations where coiling it
> >> up would make a system work better, but you won't run into them in a
> >> jeep using a commercially available antenna.
> >>
> >> Howard.
> >>
> >> On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
> >> <thomas@OBVIOUSrubicons.com> wrote:
> >>
> >> >The rule of thumb is to be 3 ft. from any other antennas. Shortening
> >> >your coax run in your TJ is not going to help your transmit range. Just
> >> >make sure you don't leave a coil of coax somewhere.
> >> >
> >> >TW wrote:
> >> >
> >> >> I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
> >> >> will be spent installing it.
> >> >>
> >> >> I was thinking how would it look if I could somehow install the CB antenna
> >> >> on the exact opposite side of the radio antenna (same height and spot). My
> >> >> radio antenna is on the right side of the TJ, CB antenna on the left side
> >> >> would ensure coax is shortest and the antenna would be somewhat in the
> >> >> middle of the truck (though to one side). Any ideas or photos of such an
> >> >> install?
> >> >>
> >> >> Thanks for all the help guys. Its much appreciated.
Guest
Posts: n/a
Re: CB Radio or PRS - Update -(long & semi OT)
Well, never could turn down a Keith's! Even if I do end up buying. ;-)
I can see what you are saying, if done right no issues.
I guess I just see a lot of crappie installs that 'do' interfere with
onboard systems and am used to the 900 mhz stuff.
I also have a big ball of antenna cable stuck in-between the fiberglass
body layers I wouldn't mind getting rid of.
Mike
Howard Eisenhauer wrote:
>
> Mike, I hope I didn't come across the wrong way on this, I have no
> desire to start a flame war over this. You have, IMHO, a well
> deserved reputation on this group for knowing your stuff, but I still
> think you're wrong.
>
> My position on this comes from being an electronics technician
> working in the radio field for somewheres on the upper side of 30
> years. An awful lot of that time has been spent testing &
> troubleshooting antenna & transmission lines on everything from
> microwave relay links to CBs, with a bunch of cell tower & military
> stuff in between. I think by now I'm pretty well grounded in both the
> theory & the practice.
>
> As far as CBs are concerned, if your antenna is properly designed &
> installed then the length of the coax line & whether or not the coax
> is coiled up is immaterial to the operation of the system. If there's
> a problem with the installation then you may well have problems with
> the coax radiating the reflected power that was supposed to go out the
> antenna. You may also experience the signal trying to get to ground
> through you power cabling instead of the coax shield. In this case
> you may well have interferance problems inside the vehicle & changing
> the length of the coax may affect your SWR meter's reading, but
> changing the length to make the meter read "right" is really only
> covering up the problem. The best way to check the SWR is with the
> meter inserted into the line right at the antenna, unfortunately the
> way most antennas are built makes this difficult. To get the real
> picture of whats happening from the radio end of the line requires an
> antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
> did I mention "$$$"?).
>
> I saw what you said about the problems you were having with your fleet
> vehicles & the data systems, I've seen it too. When the digital
> "TDMA" vehicle mount cell phones came out, we really had to crack down
> on the installers to get the VSWR down as far as possible, otherwise
> the bit error rate went crazy. We also made them trim the coax to
> "just long enough" in order to eliminate the loss from the extra
> length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
>
> If your SWR is high & you can't do anything about the antenna then you
> can reduce to problems inside the vehicle by (gasp) looping the coax a
> few times at the antenna to form an rf choke, this prevents the
> reflected signal from travelling back down the outside of the coax.
> Another trick that works is to get one of those ferrite sleeves that
> you see showing up on power & telephone cables these days. Stick it
> over the coax at the base of the antenna & it'll do the same thing as
> the loops. Running the power leads through one of these things
> wouldn't hurt either.
>
> Tell ya what- next time you're in Halifax drop me a note, I'll get
> some test equipment togeather & I'll try to show to prove to you in
> person what I'm saying is right. If I'm wrong I'll buy you a 24, If
> I'm right you do the buying, How's that?
>
> -Howard.
>
> p.s.- I drink Keith's :).
>
> On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
> wrote:
>
> >You are mistaken.
> >
> >The coil can act as a pickup for noise and it can put out RF.
> >
> >You should really read the TSB out on how to install a transmitter into
> >a new modern vehicle or you will void your vehicle warranty.
> >
> >The antenna cable can and will interfere with the vehicle's onboard
> >electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
> >Jeep automatic tranny module so every time you key up you go into
> >neutral. It also will interfere with the fuel injectors.
> >
> >GM, Chrysler and all the rest have booklets out now on how to properly
> >wire a transmitter in order to avoid voiding the vehicle warranty.
> >
> >GM insists on minimum 10 ga. power and ground run right to the battery
> >and double fused there on the opposite side of the vehicle from the
> >wiring harness. The antenna must run on the opposite side from the
> >harness too.
> >
> >So for the power lines, to have a CB on the center or passenger side of
> >a GM van, the wires have to run up the passenger side fender to the
> >front of the vehicle, across the front of the radiator supports and back
> >to the battery. If you run them across the firewall, you void the
> >warranty for the vehicle's electronics, all of them.
> >
> >Mike
> >86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >88 Cherokee 235 BFG AT's
> >
> >Howard Eisenhauer wrote:
> >>
> >> TW, another old wive's tale about the coiled coax thing. If
> >> everything is working the way it should all the signal travels through
> >> the coax between the center conductor & the inside of the braid, not
> >> along the outside where coiling it would have any effect. Coiling it,
> >> tying it up or crocheting it for that matter will not make any
> >> differencet :). There are actually some situations where coiling it
> >> up would make a system work better, but you won't run into them in a
> >> jeep using a commercially available antenna.
> >>
> >> Howard.
> >>
> >> On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
> >> <thomas@OBVIOUSrubicons.com> wrote:
> >>
> >> >The rule of thumb is to be 3 ft. from any other antennas. Shortening
> >> >your coax run in your TJ is not going to help your transmit range. Just
> >> >make sure you don't leave a coil of coax somewhere.
> >> >
> >> >TW wrote:
> >> >
> >> >> I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
> >> >> will be spent installing it.
> >> >>
> >> >> I was thinking how would it look if I could somehow install the CB antenna
> >> >> on the exact opposite side of the radio antenna (same height and spot). My
> >> >> radio antenna is on the right side of the TJ, CB antenna on the left side
> >> >> would ensure coax is shortest and the antenna would be somewhat in the
> >> >> middle of the truck (though to one side). Any ideas or photos of such an
> >> >> install?
> >> >>
> >> >> Thanks for all the help guys. Its much appreciated.
I can see what you are saying, if done right no issues.
I guess I just see a lot of crappie installs that 'do' interfere with
onboard systems and am used to the 900 mhz stuff.
I also have a big ball of antenna cable stuck in-between the fiberglass
body layers I wouldn't mind getting rid of.
Mike
Howard Eisenhauer wrote:
>
> Mike, I hope I didn't come across the wrong way on this, I have no
> desire to start a flame war over this. You have, IMHO, a well
> deserved reputation on this group for knowing your stuff, but I still
> think you're wrong.
>
> My position on this comes from being an electronics technician
> working in the radio field for somewheres on the upper side of 30
> years. An awful lot of that time has been spent testing &
> troubleshooting antenna & transmission lines on everything from
> microwave relay links to CBs, with a bunch of cell tower & military
> stuff in between. I think by now I'm pretty well grounded in both the
> theory & the practice.
>
> As far as CBs are concerned, if your antenna is properly designed &
> installed then the length of the coax line & whether or not the coax
> is coiled up is immaterial to the operation of the system. If there's
> a problem with the installation then you may well have problems with
> the coax radiating the reflected power that was supposed to go out the
> antenna. You may also experience the signal trying to get to ground
> through you power cabling instead of the coax shield. In this case
> you may well have interferance problems inside the vehicle & changing
> the length of the coax may affect your SWR meter's reading, but
> changing the length to make the meter read "right" is really only
> covering up the problem. The best way to check the SWR is with the
> meter inserted into the line right at the antenna, unfortunately the
> way most antennas are built makes this difficult. To get the real
> picture of whats happening from the radio end of the line requires an
> antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
> did I mention "$$$"?).
>
> I saw what you said about the problems you were having with your fleet
> vehicles & the data systems, I've seen it too. When the digital
> "TDMA" vehicle mount cell phones came out, we really had to crack down
> on the installers to get the VSWR down as far as possible, otherwise
> the bit error rate went crazy. We also made them trim the coax to
> "just long enough" in order to eliminate the loss from the extra
> length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
>
> If your SWR is high & you can't do anything about the antenna then you
> can reduce to problems inside the vehicle by (gasp) looping the coax a
> few times at the antenna to form an rf choke, this prevents the
> reflected signal from travelling back down the outside of the coax.
> Another trick that works is to get one of those ferrite sleeves that
> you see showing up on power & telephone cables these days. Stick it
> over the coax at the base of the antenna & it'll do the same thing as
> the loops. Running the power leads through one of these things
> wouldn't hurt either.
>
> Tell ya what- next time you're in Halifax drop me a note, I'll get
> some test equipment togeather & I'll try to show to prove to you in
> person what I'm saying is right. If I'm wrong I'll buy you a 24, If
> I'm right you do the buying, How's that?
>
> -Howard.
>
> p.s.- I drink Keith's :).
>
> On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
> wrote:
>
> >You are mistaken.
> >
> >The coil can act as a pickup for noise and it can put out RF.
> >
> >You should really read the TSB out on how to install a transmitter into
> >a new modern vehicle or you will void your vehicle warranty.
> >
> >The antenna cable can and will interfere with the vehicle's onboard
> >electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
> >Jeep automatic tranny module so every time you key up you go into
> >neutral. It also will interfere with the fuel injectors.
> >
> >GM, Chrysler and all the rest have booklets out now on how to properly
> >wire a transmitter in order to avoid voiding the vehicle warranty.
> >
> >GM insists on minimum 10 ga. power and ground run right to the battery
> >and double fused there on the opposite side of the vehicle from the
> >wiring harness. The antenna must run on the opposite side from the
> >harness too.
> >
> >So for the power lines, to have a CB on the center or passenger side of
> >a GM van, the wires have to run up the passenger side fender to the
> >front of the vehicle, across the front of the radiator supports and back
> >to the battery. If you run them across the firewall, you void the
> >warranty for the vehicle's electronics, all of them.
> >
> >Mike
> >86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >88 Cherokee 235 BFG AT's
> >
> >Howard Eisenhauer wrote:
> >>
> >> TW, another old wive's tale about the coiled coax thing. If
> >> everything is working the way it should all the signal travels through
> >> the coax between the center conductor & the inside of the braid, not
> >> along the outside where coiling it would have any effect. Coiling it,
> >> tying it up or crocheting it for that matter will not make any
> >> differencet :). There are actually some situations where coiling it
> >> up would make a system work better, but you won't run into them in a
> >> jeep using a commercially available antenna.
> >>
> >> Howard.
> >>
> >> On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
> >> <thomas@OBVIOUSrubicons.com> wrote:
> >>
> >> >The rule of thumb is to be 3 ft. from any other antennas. Shortening
> >> >your coax run in your TJ is not going to help your transmit range. Just
> >> >make sure you don't leave a coil of coax somewhere.
> >> >
> >> >TW wrote:
> >> >
> >> >> I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
> >> >> will be spent installing it.
> >> >>
> >> >> I was thinking how would it look if I could somehow install the CB antenna
> >> >> on the exact opposite side of the radio antenna (same height and spot). My
> >> >> radio antenna is on the right side of the TJ, CB antenna on the left side
> >> >> would ensure coax is shortest and the antenna would be somewhat in the
> >> >> middle of the truck (though to one side). Any ideas or photos of such an
> >> >> install?
> >> >>
> >> >> Thanks for all the help guys. Its much appreciated.
Guest
Posts: n/a
Re: CB Radio or PRS - Update -(long & semi OT)
Well, never could turn down a Keith's! Even if I do end up buying. ;-)
I can see what you are saying, if done right no issues.
I guess I just see a lot of crappie installs that 'do' interfere with
onboard systems and am used to the 900 mhz stuff.
I also have a big ball of antenna cable stuck in-between the fiberglass
body layers I wouldn't mind getting rid of.
Mike
Howard Eisenhauer wrote:
>
> Mike, I hope I didn't come across the wrong way on this, I have no
> desire to start a flame war over this. You have, IMHO, a well
> deserved reputation on this group for knowing your stuff, but I still
> think you're wrong.
>
> My position on this comes from being an electronics technician
> working in the radio field for somewheres on the upper side of 30
> years. An awful lot of that time has been spent testing &
> troubleshooting antenna & transmission lines on everything from
> microwave relay links to CBs, with a bunch of cell tower & military
> stuff in between. I think by now I'm pretty well grounded in both the
> theory & the practice.
>
> As far as CBs are concerned, if your antenna is properly designed &
> installed then the length of the coax line & whether or not the coax
> is coiled up is immaterial to the operation of the system. If there's
> a problem with the installation then you may well have problems with
> the coax radiating the reflected power that was supposed to go out the
> antenna. You may also experience the signal trying to get to ground
> through you power cabling instead of the coax shield. In this case
> you may well have interferance problems inside the vehicle & changing
> the length of the coax may affect your SWR meter's reading, but
> changing the length to make the meter read "right" is really only
> covering up the problem. The best way to check the SWR is with the
> meter inserted into the line right at the antenna, unfortunately the
> way most antennas are built makes this difficult. To get the real
> picture of whats happening from the radio end of the line requires an
> antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
> did I mention "$$$"?).
>
> I saw what you said about the problems you were having with your fleet
> vehicles & the data systems, I've seen it too. When the digital
> "TDMA" vehicle mount cell phones came out, we really had to crack down
> on the installers to get the VSWR down as far as possible, otherwise
> the bit error rate went crazy. We also made them trim the coax to
> "just long enough" in order to eliminate the loss from the extra
> length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
>
> If your SWR is high & you can't do anything about the antenna then you
> can reduce to problems inside the vehicle by (gasp) looping the coax a
> few times at the antenna to form an rf choke, this prevents the
> reflected signal from travelling back down the outside of the coax.
> Another trick that works is to get one of those ferrite sleeves that
> you see showing up on power & telephone cables these days. Stick it
> over the coax at the base of the antenna & it'll do the same thing as
> the loops. Running the power leads through one of these things
> wouldn't hurt either.
>
> Tell ya what- next time you're in Halifax drop me a note, I'll get
> some test equipment togeather & I'll try to show to prove to you in
> person what I'm saying is right. If I'm wrong I'll buy you a 24, If
> I'm right you do the buying, How's that?
>
> -Howard.
>
> p.s.- I drink Keith's :).
>
> On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
> wrote:
>
> >You are mistaken.
> >
> >The coil can act as a pickup for noise and it can put out RF.
> >
> >You should really read the TSB out on how to install a transmitter into
> >a new modern vehicle or you will void your vehicle warranty.
> >
> >The antenna cable can and will interfere with the vehicle's onboard
> >electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
> >Jeep automatic tranny module so every time you key up you go into
> >neutral. It also will interfere with the fuel injectors.
> >
> >GM, Chrysler and all the rest have booklets out now on how to properly
> >wire a transmitter in order to avoid voiding the vehicle warranty.
> >
> >GM insists on minimum 10 ga. power and ground run right to the battery
> >and double fused there on the opposite side of the vehicle from the
> >wiring harness. The antenna must run on the opposite side from the
> >harness too.
> >
> >So for the power lines, to have a CB on the center or passenger side of
> >a GM van, the wires have to run up the passenger side fender to the
> >front of the vehicle, across the front of the radiator supports and back
> >to the battery. If you run them across the firewall, you void the
> >warranty for the vehicle's electronics, all of them.
> >
> >Mike
> >86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >88 Cherokee 235 BFG AT's
> >
> >Howard Eisenhauer wrote:
> >>
> >> TW, another old wive's tale about the coiled coax thing. If
> >> everything is working the way it should all the signal travels through
> >> the coax between the center conductor & the inside of the braid, not
> >> along the outside where coiling it would have any effect. Coiling it,
> >> tying it up or crocheting it for that matter will not make any
> >> differencet :). There are actually some situations where coiling it
> >> up would make a system work better, but you won't run into them in a
> >> jeep using a commercially available antenna.
> >>
> >> Howard.
> >>
> >> On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
> >> <thomas@OBVIOUSrubicons.com> wrote:
> >>
> >> >The rule of thumb is to be 3 ft. from any other antennas. Shortening
> >> >your coax run in your TJ is not going to help your transmit range. Just
> >> >make sure you don't leave a coil of coax somewhere.
> >> >
> >> >TW wrote:
> >> >
> >> >> I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
> >> >> will be spent installing it.
> >> >>
> >> >> I was thinking how would it look if I could somehow install the CB antenna
> >> >> on the exact opposite side of the radio antenna (same height and spot). My
> >> >> radio antenna is on the right side of the TJ, CB antenna on the left side
> >> >> would ensure coax is shortest and the antenna would be somewhat in the
> >> >> middle of the truck (though to one side). Any ideas or photos of such an
> >> >> install?
> >> >>
> >> >> Thanks for all the help guys. Its much appreciated.
I can see what you are saying, if done right no issues.
I guess I just see a lot of crappie installs that 'do' interfere with
onboard systems and am used to the 900 mhz stuff.
I also have a big ball of antenna cable stuck in-between the fiberglass
body layers I wouldn't mind getting rid of.
Mike
Howard Eisenhauer wrote:
>
> Mike, I hope I didn't come across the wrong way on this, I have no
> desire to start a flame war over this. You have, IMHO, a well
> deserved reputation on this group for knowing your stuff, but I still
> think you're wrong.
>
> My position on this comes from being an electronics technician
> working in the radio field for somewheres on the upper side of 30
> years. An awful lot of that time has been spent testing &
> troubleshooting antenna & transmission lines on everything from
> microwave relay links to CBs, with a bunch of cell tower & military
> stuff in between. I think by now I'm pretty well grounded in both the
> theory & the practice.
>
> As far as CBs are concerned, if your antenna is properly designed &
> installed then the length of the coax line & whether or not the coax
> is coiled up is immaterial to the operation of the system. If there's
> a problem with the installation then you may well have problems with
> the coax radiating the reflected power that was supposed to go out the
> antenna. You may also experience the signal trying to get to ground
> through you power cabling instead of the coax shield. In this case
> you may well have interferance problems inside the vehicle & changing
> the length of the coax may affect your SWR meter's reading, but
> changing the length to make the meter read "right" is really only
> covering up the problem. The best way to check the SWR is with the
> meter inserted into the line right at the antenna, unfortunately the
> way most antennas are built makes this difficult. To get the real
> picture of whats happening from the radio end of the line requires an
> antenna line analyzer ($$$- google "Anritsu Sitemaster" for one model,
> did I mention "$$$"?).
>
> I saw what you said about the problems you were having with your fleet
> vehicles & the data systems, I've seen it too. When the digital
> "TDMA" vehicle mount cell phones came out, we really had to crack down
> on the installers to get the VSWR down as far as possible, otherwise
> the bit error rate went crazy. We also made them trim the coax to
> "just long enough" in order to eliminate the loss from the extra
> length, which admittedly is a lot worse @ 850 Mhz than 27 ;>.
>
> If your SWR is high & you can't do anything about the antenna then you
> can reduce to problems inside the vehicle by (gasp) looping the coax a
> few times at the antenna to form an rf choke, this prevents the
> reflected signal from travelling back down the outside of the coax.
> Another trick that works is to get one of those ferrite sleeves that
> you see showing up on power & telephone cables these days. Stick it
> over the coax at the base of the antenna & it'll do the same thing as
> the loops. Running the power leads through one of these things
> wouldn't hurt either.
>
> Tell ya what- next time you're in Halifax drop me a note, I'll get
> some test equipment togeather & I'll try to show to prove to you in
> person what I'm saying is right. If I'm wrong I'll buy you a 24, If
> I'm right you do the buying, How's that?
>
> -Howard.
>
> p.s.- I drink Keith's :).
>
> On Tue, 13 Apr 2004 10:10:35 -0400, Mike Romain <romainm@sympatico.ca>
> wrote:
>
> >You are mistaken.
> >
> >The coil can act as a pickup for noise and it can put out RF.
> >
> >You should really read the TSB out on how to install a transmitter into
> >a new modern vehicle or you will void your vehicle warranty.
> >
> >The antenna cable can and will interfere with the vehicle's onboard
> >electronics. It 'Will' cut out anti-lock brakes. It 'will' cut out a
> >Jeep automatic tranny module so every time you key up you go into
> >neutral. It also will interfere with the fuel injectors.
> >
> >GM, Chrysler and all the rest have booklets out now on how to properly
> >wire a transmitter in order to avoid voiding the vehicle warranty.
> >
> >GM insists on minimum 10 ga. power and ground run right to the battery
> >and double fused there on the opposite side of the vehicle from the
> >wiring harness. The antenna must run on the opposite side from the
> >harness too.
> >
> >So for the power lines, to have a CB on the center or passenger side of
> >a GM van, the wires have to run up the passenger side fender to the
> >front of the vehicle, across the front of the radiator supports and back
> >to the battery. If you run them across the firewall, you void the
> >warranty for the vehicle's electronics, all of them.
> >
> >Mike
> >86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >88 Cherokee 235 BFG AT's
> >
> >Howard Eisenhauer wrote:
> >>
> >> TW, another old wive's tale about the coiled coax thing. If
> >> everything is working the way it should all the signal travels through
> >> the coax between the center conductor & the inside of the braid, not
> >> along the outside where coiling it would have any effect. Coiling it,
> >> tying it up or crocheting it for that matter will not make any
> >> differencet :). There are actually some situations where coiling it
> >> up would make a system work better, but you won't run into them in a
> >> jeep using a commercially available antenna.
> >>
> >> Howard.
> >>
> >> On Mon, 12 Apr 2004 14:40:20 GMT, twaldron
> >> <thomas@OBVIOUSrubicons.com> wrote:
> >>
> >> >The rule of thumb is to be 3 ft. from any other antennas. Shortening
> >> >your coax run in your TJ is not going to help your transmit range. Just
> >> >make sure you don't leave a coil of coax somewhere.
> >> >
> >> >TW wrote:
> >> >
> >> >> I went out and bought an AM CB radio (Uniden Pro 510XL). Now the weekend
> >> >> will be spent installing it.
> >> >>
> >> >> I was thinking how would it look if I could somehow install the CB antenna
> >> >> on the exact opposite side of the radio antenna (same height and spot). My
> >> >> radio antenna is on the right side of the TJ, CB antenna on the left side
> >> >> would ensure coax is shortest and the antenna would be somewhat in the
> >> >> middle of the truck (though to one side). Any ideas or photos of such an
> >> >> install?
> >> >>
> >> >> Thanks for all the help guys. Its much appreciated.
