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Discussion Starter #1
I recently tuned my CB stuff and found that my SWR was super high. I built a new mount and tightened stuff here and there, that brought SWR down to a safe level. Then I fine tuned the antenna to even it out on all channels, I cut the cover and moved a couple of turns of wire up (just like on the firestik site) thats when a funny thing happened, the ANT light started coming on on channels above 13. I bought a new fire stik antenna saturday but that made it worse (now it's on all channels), the SWR is nice and low but the ANT light still comes on. I can send/recieve well most of the time, some times it fades in and out.

any ideas?
 

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Cleaning the trails
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Take the connector off the back of the radio. Connect a VOM to the center pin and the shield. You should have no continuity there. If you do, you have a short somewhere. Very radio unfriendly. Also check the continuity from the shield to ground. Should have continuity. If the cable is long enough to reach to the antenna, check the continuity from the center pin to the base of the antenna where it screws into the mount. You may have to get a piece of wire to go from the base of the antenna to the center pin. You should have continuity there

More than likely it is a bad connector on the cable where it connects to the radio. I make mine, so I know what I have. The premade ones are prone to problems.

Look at the base of the antenna and verify that the center conductor and shield are not touching in any way. If you can post pics of the install it may help!

Good luck. Finding these gremlins can be time consuming if you have not dealt with this before.

If you are ever in the Inland Empire (way down south from you), stop by and we can troubleshoot it.
 

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Discussion Starter #5
Thanks Tony! wow, good advice-- I'll check it all out tomorrow and let you know, it looks like it may be ground because the mount is painted and mounted on a painted body panel.:banghead We'll see though, pics too!
 

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Discussion Starter #6
Ok, The center pins have continuity, the pin and shield has none. There is continuity from the ground to the shield. It all seems to check out. Would a thicker coax make thing better?

Edit: I tried taking out the spring, SWR went up, same results with the ANT light

 

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Cleaning the trails
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OK, usually a 1/4" or more will change the SWR drastically. A few turns would be about an inch or so. To do a quick check, take out the spring and check the SWR. See what happens. Check to see if the SWR is higher on CH 1 or CH 40 with the spring out. Let me know what the readings are on Ch 1 and Ch 40 without the spring. The spring adds 4-6 inches to what the radio sees as antenna length. This will dtermine if we need to add wire back in or remove.
 

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Discussion Starter #8
Sorry, I was gone for the weekend, I suspected it was the radio so I picked up a new 29 at radioshack and all my probs disappeared! SWR is now 1.1-1.2 on all channels and I can transmit and receive super clearly, WAY better than before.

I haven't tuned the antenna either, I kinda don't want to mess with near perfection

Tony- thanks for all the help man!:beer
 

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glad u got it fixed, i was looking at your pics and noticed the ''spacer'' between the mt. and the spring ,i've never seen this done.
iknow u said everything working good now,but u should try doing away with the spacer and mount the spring staight onto the center theaded rod coming from the coax mount,
your new radio might have solved the promblem for now but i think your ant. might cause your new radio to go ''south''
i know this might sound confussing, so maybe somebody else saw your pics and can chime in on this
 

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That is the way that mount is designed. Without it, there is no way to isolate the center conductor from the ground. Short the antenna to the gorund and you burn up the finals in the radio.

Glad to hear the issues went away!!!
 

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Discussion Starter #11
Exactly, the mount has a bolt that runs up through that hole and in order to isolate the antenna from the ground there must be a non-conductive spacer between them.
 

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i dont mean the white plastic one , i mean the chrome 1'' inch tall conector between spring and white plastic isolator.

i dont think it is needed, but been wrong before C-YA!:rebelflag



are the coils of the spings part of the gound? and isnt there an internal conductor running inside them?

something just doesnt look corrent guys! wheres bronco rob and gacknar when i need um? oh well
 

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Discussion Starter #13
Oh, that spacer! That has threads on the inside so you can screw the antenna (or spring) in on the top and that bolt I was talking about screws in on the bottom. The spring is part of the antenna itself, not the ground, and yes there is an internal conductor inside.

Actually it all looks ok to me, and my SWR is 1.1 to 1.2 on all channels so I think electrically it's good to go as well.
 

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Discussion Starter #15
10-4:rockon

You sig only appears once per page. It makes the pages load faster. Sometimes you can trick it by editing your post but once you leave the page it disappears.
 

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Does anyone still read this page?
 
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