CB Tuning Question (Doors & Top)?
04-14-2008, 05:10 PM
#11
JK Super Freak
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Location: Barrie Ontario, CANADA
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I just hooked up my cb this weekend, took it to a cb shop today, and he said that where we have them mounted below the roof and in behind the tire is part of the reason for the swr reading high, He told me my low channels are acceptable and not to use the really high ones, so 20 and down suits me just fine.
04-14-2008, 05:12 PM
#12
JK Super Freak
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I have read hundreds of posts on here and information on other sites about how to tune the antenna, but I haven't heard of anyone with the Cobra 75 and a Firestick 4' having to cut the antenna to tune right. 
Here are some pictures of my set-up:
Will grounding to the battery work the best? the 75 box is under the glove compartment.
My SWR ratings are 1.8 on Channel 1; and 2.8 on Channel 40. I have taken the QD off and taken out the tuning rod, and that is the best I can get.
Please let me know what I am doing wrong. Supposed to go on the trails tomorrow and would like it working by then. Appreciate it!
Here are some pictures of my set-up:
Will grounding to the battery work the best? the 75 box is under the glove compartment.
My SWR ratings are 1.8 on Channel 1; and 2.8 on Channel 40. I have taken the QD off and taken out the tuning rod, and that is the best I can get.
Please let me know what I am doing wrong. Supposed to go on the trails tomorrow and would like it working by then. Appreciate it!
04-14-2008, 06:39 PM
#14
JK Enthusiast
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04-14-2008, 07:17 PM
#15
JK Super Freak
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I used the radio shack mount and drilled the bolts into the license plate cover. I then ran a groun from the bolt to the frame directly and then attached the antenna ground to the bolt. I wish I had pic's but we are waiting on a camera my wife just ordered because the other one crapped the bed. If I would do it again I would of put it on the tire carrier mount system and run the ground from there. I got good readings but I think the CB is got issues so let's see if this changes when the new one comes in a few days.
04-15-2008, 01:37 PM
#16
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my first suggestion to you is get rid of the quick disconnect ! That is adding to a higher swr reading. I had the same issue. I have a custom length firestick. It is just under 6ft. high and has a tuneable tip. I have the same mount to the tire rack as you. That mount is self grounding! So no need to mound a grounding wire. I will get the guys name I got my antenna from and post it here when I get home. I would go to a CB shop and have them peal the radio and use a external swr reader to tune you setup. Should cost around 50-60 bucks for the peaking and 20 or so to tune the set up. I have an original Cobra 29 old style that's been peaked. I have a swr under 1 on both channels 1 and 40. I acne talk about 10 - 15 miles depending on surrounding landscape.
04-17-2008, 05:55 PM
#18
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my first suggestion to you is get rid of the quick disconnect ! That is adding to a higher swr reading. I had the same issue. I have a custom length firestick. It is just under 6ft. high and has a tuneable tip. I have the same mount to the tire rack as you. That mount is self grounding! So no need to mound a grounding wire. I will get the guys name I got my antenna from and post it here when I get home. I would go to a CB shop and have them peal the radio and use a external swr reader to tune you setup. Should cost around 50-60 bucks for the peaking and 20 or so to tune the set up. I have an original Cobra 29 old style that's been peaked. I have a swr under 1 on both channels 1 and 40. I acne talk about 10 - 15 miles depending on surrounding landscape.
04-17-2008, 06:56 PM
#19
Rubi-WAC,
I had the same setup and had to ground my tailgate in order to get a good SWR. As far as the doors and top go, I tested with about every configuration and neither made a difference. The tops don't interfere at all since neither are made of metal. I did not have to trim the antenna, but then again I got the tunable tip rather than the trim type.
Feel free to PM me if you have any questions or need any help getting it setup. I've since relocated my antenna to my bumper and have even better SWR now.
I had the same setup and had to ground my tailgate in order to get a good SWR. As far as the doors and top go, I tested with about every configuration and neither made a difference. The tops don't interfere at all since neither are made of metal. I did not have to trim the antenna, but then again I got the tunable tip rather than the trim type.
Feel free to PM me if you have any questions or need any help getting it setup. I've since relocated my antenna to my bumper and have even better SWR now.
04-19-2008, 02:55 AM
#20
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HiJACK! Ok techies, here is a good one. I have a Cobra 75, install is under glove compartment, cooltech mount with associated firestick. Power to battery, ground to frame. I had external swr readings around 1.5 up and down the channel renge and loads of reception. Great huh?
I next bought a cool tech qucik disco for the antenna AND installed a garmin Trail Guide with on dash docking station (Jeep specific setup).This GPS configurtion resulted in my handset being mounted a few inches from the right speaker of the GPS docking station. I started to notice my CB seemed "quieter" with less reception. Also, I noticed my SCAN feature stopped working. I put my SWR meter on the radio thinking the quick disco required new tuning to the antenna. The SWR meter went off the chart on all channels. I removed the antenna quick diso to simulate my previously successful setup and the meter still goes off the chart. I've moved the tuning screw up and down its full range. I tried moving the handset away from the GPS mount and still got SWR readings OFF THE CHART. I've also noticed that with the CB on and handset mounted on the bracket, hand movement towards the handset cause static to warp as I get closer to the mike. So, I'm at a loss. I guess I could remove the docking station to check it's impact on this senario, but its kinda a perminant install location. Could the speakers (maginate) in the docking station be causing this problem? HELP HELP HELP
I next bought a cool tech qucik disco for the antenna AND installed a garmin Trail Guide with on dash docking station (Jeep specific setup).This GPS configurtion resulted in my handset being mounted a few inches from the right speaker of the GPS docking station. I started to notice my CB seemed "quieter" with less reception. Also, I noticed my SCAN feature stopped working. I put my SWR meter on the radio thinking the quick disco required new tuning to the antenna. The SWR meter went off the chart on all channels. I removed the antenna quick diso to simulate my previously successful setup and the meter still goes off the chart. I've moved the tuning screw up and down its full range. I tried moving the handset away from the GPS mount and still got SWR readings OFF THE CHART. I've also noticed that with the CB on and handset mounted on the bracket, hand movement towards the handset cause static to warp as I get closer to the mike. So, I'm at a loss. I guess I could remove the docking station to check it's impact on this senario, but its kinda a perminant install location. Could the speakers (maginate) in the docking station be causing this problem? HELP HELP HELP