2nd Gen Non-Engine/Transmission Radio reception/antenna ground

[WBusa]

Hi folks. I'm new to TDR, having just bought my first diesel, but reading over these forums has already solved three or four problems for me. Here's one I haven't seen discussed yet:



Our 'new' '95 2500's radio reception sucked - the stock radio/tape player hardly pulled in any stations (we live out in the boonies, but not THAT far out... my Ford Windstar and Subaru have no problems with reception). Decided to replace the stock radio with a new radio/CD player, but saw no improvement in reception. The installer told us that the end of the antenna wire he dealt with looked fine.



So I inspected the other end of the antenna wire. I unscrewed the mast, then unscrewed the chromed nut, lifted off the black plastic cowl, and retracted the antenna mount (metal thingy onto which the mast screws and to which the antenna wire is crimped) from its hole in the fender ,through the engine compartment. All looked OK. When I screwed the mast back onto the antenna mount WITHOUT replacing the mount in the fender (i. e. , just let the mount hang in midair, without touching anything) reception is GREAT. But when I touch the antenna mount to the fender, reception dies. There was no washer or anything isolating the mount from the fender metal before I disassembled it, so of course this is the source of my reception problem.



I tried to electrically isolate the mount from the fender metal by wrapping it up in electrical tape, and when I reinstalled everything reception was great as long as I didn't tighten down the chromed nut very much at all (since doing so tends to move the electrical tape). Of course, without the nut tightened down firmly, bumps and wind whipping the antenna soon screw things up again, so I lose reception.



My question: was there supposed to be a washer or something isolating the antenna mount from the inside of the fender metal? If not, then why am I losing reception when the mount touches the fender? Many thanks!

 

[B.G. Smith]

You need to get another antenni. The mounting part and the external part of the coax should be grounded but of course not the center lead. bg

 

[John - K5AWO]

I agree, it is far cheaper to replace the antenna and cable assembly than to screw around and try to replace/repair what the installer broke or lost. The isolator at the base mount.



Most likely when it was done, the owner lived near some radio stations and figured that was "as good as it gets. " Have I heard that phrase before??

 

[WBusa]

Thanks for the recommendations. I'm going to try another quick fix (heat-shrink tubing) before I give up and buy a replacement, mostly because I hate throwing out things that can be made to work. In my ill-spent youth, driving VW bugs, I used to patch exhaust leaks with a tomato paste can and two hose clamps... a Contadina can would get you from San Francisco to San Diego, but Hunts cans would give out by Santa Barbara

 

[esdd]

There is a short in the coax between the antenna and the radio, when you ground the shield you effectievely short the entire antenna. as others have said replace the whole d##n mess and be done with it.