Grounding radio head unit

[Klutch9]

Got a bit of an odd situation here... a couple of months back, I replaced the head unit in my van with a cheap aftermarket one. I did this purely because I wanted an AUX input. However, I noticed upon installation that the radio reception is terribly fuzzy and full of static in urban areas (closer to Detroit). Many of the local radio and TV stations broadcast from within the city, or just outside of it. You'd think that being close to the transmission point would help, not hurt. Antenna wiring is fine, and securely in place in the head unit. Then I got to thinking of something...

The OEM radio has a metal chassis that connects to the metal dash support. The aftermarket radio also has a metal chassis, but because it sits inside of a plastic adapter, it does not actually touch the metal dash support. The only grounding that is present is through the negative wire in the harness. Should I add an additional ground between the head unit directly to the dash support? I don't recall having this issue with aftermarket head units in the past. FWIW, others have commented online about poor radio reception with the model as well. Again, it isn't range that's an issue; it's when I'm in close proximity to the broadcasts that the signals get full of static.

 

[Klutch9]

I should also add that my head unit has a 'local' and 'distance' setting. I've had it set to local, but I guess I could give the distance setting a try.

 

[Jimmy9190]

The outer shield of the antenna coax cable is connected to ground through the chassis of the van so it also connects to the case of the radio when the antenna is plugged in. You may not get much improvement by grounding the radio case itself but it can be worth a try. Does the radio have a local tuning function? If it does, try turning it on when in the city. That is what local tuning is designed for, to cut out interference when you are near a higher powered station or near one or more radio transmission towers.

 

[Jimmy9190]

Originally Posted By: Klutch9
I should also add that my head unit has a 'local' and 'distance' setting. I've had it set to local, but I guess I could give the distance setting a try.


You typed your response while I typed mine. If local tuning does not help you may need to use a different brand of radio.

 

[Nitronoise]

I have a similar problem with my sons jeep and when installing 2 way radios in public safety vehicles you always have to have a good ground and the ground for the power line is usually fused on kenwoods,

run a wire from the frame of the radio to the dashboard and see if that improves reception , and check your coax antenna line for corrosion internally as MI uses some very aggressive de-icing compounds known to wreak havoc with electrical equipment on heavy duty trucks

 

[HerrStig]

A good "ground" never hurts. But it sounds like the "front end" of your receiver is unable to handle a number of strong signals at the same time. It's called "desense" and the effect is to make the receiver seem deaf. If you have an old style segmented whip antenna, make it shorter and see if it helps. The local/distance switch lowers the sensitivity for use close to transmitters, but
perhaps in your case, not enough. Perhaps your switch is wired backwards by mistake, otherwise going to "distance" can only make your problem worse.