Man, this is driving me a little nuts!

About two years ago, I replaced my radio with a Blaupunkt and I had the greatest reception on all channels both AM and FM. About 7 months ago, I started getting engine noise and terrible reception on the AM band. Even the strongest stations would have static and poor clarity.

I suspected the antenna, and as fate would have it, a relay blew in the antenna, and I had it overhauled. The antenna is not a problem from what I can tell as following replacement I still have the same problem. No better no worse!

The traffic reports are better on AM and if you are familiar with Washington, DC you know that I need traffic reports. I know that the answer I'll get is use FM. I can do that. I'm just a meticulous lout who can't stand things that don't work properly. Any clues from the audience?

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1988 560SL
Black Pearl/Palamino

Tom..Good AM reception is dependent on one major factor in your antenna circuit. The ground where the antenna mounts to the underneath of the fender must be perfect. By that I mean when you measure with an ohmmeter from the case of the antenna to ground of the car it must measure 0 ohms. If it does not you should either remount the antenna making sure that the area under the fender that grips the antenna is scraped clean of paint and other contaminants so the antenna gets a good ground. If this is not possible you can run a ground lead from the antenna body to a ground point near the antenna. If that does not work you must measure the resistance of the antenna lead extension that goes to the front of the car. Sometimes water gets inside the antenna lead extension and attacks the outside braid on the coax cable and increases the resistance of the ground braid to the point that the AM does not work well. I know that this might seem complicated but having diagnosed hundreds of bad AM sections of radios I know the solution is not always simple. These are just a couple of the most common failure points in AM.

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83 300CDTurbo 307,000
2005 Honda Element 266,000
56 Nash Ambassador Country Club Special 34,000(under restoration presently)

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