Filtering alternator noise

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Dear All,
I just install a TV in my car. Without turn-on the engine, the picture looks very good, clear, sharp.
As soon I start the engine, the picture become blur, and there is also stright line moving up and down and up and down.

I think this is mainly caused by the noise of the alternator.

Anybody know, how to filter the power line in automotive system?

Thanks.
 
Almost the only way is a supressor capacitor across the alternator terminals.

Don't try and do it away from the alternator as the noise is then already all over the wiring.

Since it is a TV, you may be getting pickup from the spark plug HT to the antenna inputs. This used to be very prevalent with old VHF TVs

To prove this, turn the engine over but with the LT disconnected from the coil - no sparks. The engine will not fire but if the noise doesn't change it is not HT.
 
cliff said:
Almost the only way is a supressor capacitor across the alternator terminals.

What do you mean by suspressor capacitor? Is it large value capacitor, such as 1 Farad capacitor, that usually found in car.

I was thinking simpler solution such LC filter from ACC/Key to B+ of the TV, do you think this will effectively filter the noise?

Thanks
 
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