Radio noise

Wag2+2 said:

If the radio static goes away when the alternator is turned off, would the cause be within the alternator or wiring to and from? The charging system works fine.

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1. loose screw on output breaker(would sometimes weld, other time be loose and noisy)
2. bad grond alt to airframe
3. bad master solenoid, burnt contractor?

finding gremlins...

the battery is the big noise filter, any bad connections allow noise that normal the battery will soak up and hide, to be heard....so long before adding a noise filter i hunt for bad connections...


but to find the bad conection/noisy conection... say like yours alternator sounds


first use a temporary jumper wire from the case of alternator to battery ground post, run-up test it... is sound still there? if it is gone the problem is in the ground circut, so move end of jumper that was at battery ground to next closer conection to alt (which is the other end of the battery strap at this 2nd step).... and repeat this till you find it...


if the ground directly to battery terminal did NOT make it go away.....


do a temp jumperwire from alt out terminal to battery positive terminal.......run-up test it... is sound still there? if it is gone it is in the positive side of alt output circuit, so move end of jumper that was at battery positive to next closer conection to alt (which is the other end of the battery strap at this 2nd step).....and repeat this till you find it...


and if all that did not work, then i would call it noisy alternator it self....


this has worked for me on diffrent planes to find a bad master solinod, and a coroded conection on a alt out breaker

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