Re: straight 8 engine

Posted by HH56 On 2012/11/14 15:03:20

I'm still thinking the tach may be picking up some noise on the input leads. Could be either power or signal wire or both. Since the radio is obviously picking up extraneous noise, to my mind it's only logical other things may be too.

Putting an oscilloscope on to verify what is happening is most likely out of the question so next best would be the brute force attack. Would be very curious how wire separation or a shielded cable would affect it.

It shouldn't take 10 minutes for the radio to calm down. If your radio has all it's old capacitors still present, those dry out and a bad filter capacitor could be contributing to some of the hum and noise problems. A poor ground on the antenna coax could be contributing to the problem too.