help finding ground inside C5, installing CB
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help finding ground inside C5, installing CB
I bought the Koolkat cb antenna set up for my car and I followed all of the directions but I can't get the thing to ground. I attached the ground wire to the seat stud on the floor but that isn't giving me a ground. My SWR is right around 3 on all the channels. When I grab the metal base of the antenna with my hand the swr drops to 1.5 so I know I'm not getting ground.
What do I need to do? I tried scraping the paint off of the seat rail but that didn't help either. Any ideas where I can get a good ground inside the car?
Thanks!!!
What do I need to do? I tried scraping the paint off of the seat rail but that didn't help either. Any ideas where I can get a good ground inside the car?
Thanks!!!
Melting Slicks
Joined: May 2003
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From: arlington tx
the metal framing of the console "stack" (where the radio and AC stuff is at) is excellent ground. i grouned my XM radio tuner there and it checks out awesome as a ground. my sub amp is grounded in the trunk....the ridge that goes across the car from side to side right behind the seat is metal and i used a self tapping bolt and star washer for my ground and again got an awesome ground. its covered with carpet so its not seen either.
Melting Slicks
Joined: Feb 2002
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From: Coal Valley IL
CI 4-7, 9 & 10 Veteran
That ground will work fine. I have my CB tapped into the cigarette lighter socket power. I am running a fully peaked out 31 watt Cobra 29. Since that antanna setup is inside the car, I wouldn't expect much better than a 2.0 SWR. But, 2.0 is still decent.
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Originally Posted by sebringsilver97coupe
the metal framing of the console "stack" (where the radio and AC stuff is at) is excellent ground. i grouned my XM radio tuner there and it checks out awesome as a ground. my sub amp is grounded in the trunk....the ridge that goes across the car from side to side right behind the seat is metal and i used a self tapping bolt and star washer for my ground and again got an awesome ground. its covered with carpet so its not seen either.
I tried the cigarette lighter as a ground and was very dirty power, lots of noise through the cb radio. So I drilled into the cross bar that runs behind the seat and used a self tapping screw. WOW, it finally works!!!! I got my SWR down to around 1.3 on channels 1-20 channel 40 is still around 2.4 though. Should I keep shaving off the top of my stinger to get that channel 40 down more or just leave it? I will never use the high channels anyway.
Intermediate
Joined: Jul 2004
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From: Wheaton IL
What kind of antenna are you using? I got a no-ground antenna through Firestik. My CB is powered through the cigarette lighter. It works great, both on my '82 and on my '04. My reading is just over 1.0. One of the best sites for CB info is firestik.com. Also, if you call them, they're very helpful.
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From: HOW FAST WAS I GOING OFFICER? Los Angeles Hating GM Dealership Service Dept.'s Since Sept. 2004
St. Jude Donor '04-'05-'06-'07
Under the dash on the right side of the driver's side .. kinda where your right knee would meet the dash ... there is metal. I used it to ground some electronics.
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From: Putting a 50¢ sticker of the U.S. Flag on a $50,000 import does not make one a patriot.
SWR (Standing Wave Ratio), has nothing to do with a ground connection. It has to do with reflective ground planes, not a grounded connection. Since the Vette is plactic and fiberglass, you have a poor reflective ground plane.
An SWR of 3.0 is horriable. You are loosing power and range. I would experiment with different antenna lengths to lower that SWR. 1.5 and lower is optimal.
You can also try an antenna tunner, but adjusting antenna length is the best way to go.
Read this link http://www.wilsonantenna.com/swrg.htm It has some info on SWR, and how to tune it.
AZC5
An SWR of 3.0 is horriable. You are loosing power and range. I would experiment with different antenna lengths to lower that SWR. 1.5 and lower is optimal.
You can also try an antenna tunner, but adjusting antenna length is the best way to go.
Read this link http://www.wilsonantenna.com/swrg.htm It has some info on SWR, and how to tune it.
AZC5
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From: HOW FAST WAS I GOING OFFICER? Los Angeles Hating GM Dealership Service Dept.'s Since Sept. 2004
St. Jude Donor '04-'05-'06-'07
Thank goodness someone knew what SWR was ... I was shooting with my eyes closed.
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Originally Posted by AZC5
SWR (Standing Wave Ratio), has nothing to do with a ground connection. It has to do with reflective ground planes, not a grounded connection. Since the Vette is plactic and fiberglass, you have a poor reflective ground plane.
An SWR of 3.0 is horriable. You are loosing power and range. I would experiment with different antenna lengths to lower that SWR. 1.5 and lower is optimal.
You can also try an antenna tunner, but adjusting antenna length is the best way to go.
Read this link http://www.wilsonantenna.com/swrg.htm It has some info on SWR, and how to tune it.
AZC5
An SWR of 3.0 is horriable. You are loosing power and range. I would experiment with different antenna lengths to lower that SWR. 1.5 and lower is optimal.
You can also try an antenna tunner, but adjusting antenna length is the best way to go.
Read this link http://www.wilsonantenna.com/swrg.htm It has some info on SWR, and how to tune it.
AZC5
Thanks for the information but a reading of 3.0 on the SWR meter on all channels is a result of not having a ground or having a poor one. You can tune the antenna all you want but if you are at 3.0 you are just spinning your wheels because the antenna isn't grounded properly.
Also, if you read down a little you will se I got the SWR well under 2.0 on the lower 25 channels. (after I found a good ground)
Last edited by lvvette777; Oct 22, 2004 at 12:48 PM.
Thread Starter
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Originally Posted by AZC5
SWR (Standing Wave Ratio), has nothing to do with a ground connection. It has to do with reflective ground planes, not a grounded connection. Since the Vette is plactic and fiberglass, you have a poor reflective ground plane.
An SWR of 3.0 is horriable. You are loosing power and range. I would experiment with different antenna lengths to lower that SWR. 1.5 and lower is optimal.
You can also try an antenna tunner, but adjusting antenna length is the best way to go.
Read this link http://www.wilsonantenna.com/swrg.htm It has some info on SWR, and how to tune it.
AZC5
An SWR of 3.0 is horriable. You are loosing power and range. I would experiment with different antenna lengths to lower that SWR. 1.5 and lower is optimal.
You can also try an antenna tunner, but adjusting antenna length is the best way to go.
Read this link http://www.wilsonantenna.com/swrg.htm It has some info on SWR, and how to tune it.
AZC5
This was taken out of the link you provided:
3. The SWR on a trunk lid mount is 3.0:1 on all channels.
[red]When a reading of 3.0:1 is present on all channels, this indicates a lack of ground for the antenna. [/red]For example, some of the vehicles today insulate their trunk lid from the actual chassis or frame, ground of the body. This is done by inserting plastic washers on the trunk hinges, and/or sandwiching a layer of styrofoam type material between the two piece trunk lid. To eliminate this situation, a jumper wire must be installed from the actual bottom lip of the trunk lid to metal on the body of the auto. To accomplish this, loosen one of the hinge bolts on the trunk-lid side and install a braided strap. Re-tighten the bolt. Loosen the bolt on the other side of the hinge (trunk-body side). Install the other end of the braided strap to this bolt and re-tighten. Be sure to leave a long enough loop to prevent pulling apart when the trunk lid is fully open. As added ground insurance, you may wish to add a jumper from the set screw on the trunk lip mount to the hinge bolt on the trunk-lid.
