radio interference with trolling motor

[Darrendude]

When I run the trolling motor i can here the radio. Is there something I can put inline to the radio or trolling motor to get rid of this buzzing on the radio?<br />Thanks

 

[jlinder]

Re: radio interference with trolling motor

2 ways to get interference on the radio. Either direct up the power line, or by RF<br /><br />Direct - easist to fix. To test, hook the radio to a separate power source (battery) and see if it goes away. If so, solution is to filter the power source. You should be able to pick up filters at radio shack or any electronics place. <br />You can also look towards running a separate line back to the battery to clean up the power (if you don't have that already).<br /><br />RF - this is the motor creating radio frequency noise. Either try to get a better signal (antenna?) or find out what you can do to clean up the motor. Brushes are a good thing to look at - are they clean and not worn?<br /><br />Let us know what you find out.

 

[chuckz]

Re: radio interference with trolling motor

DC motors until they are run in are very noisey. If this is a new trolling motor wait until you've run it for at least 24 hours before doing anything. Running in the brushes will probably solve the problem.<br /><br />Otherwise, the best approach is called source supression. You want to put a filter as close to the noise source as possible. This works for conducted as well as radiated noise.<br /><br />You didn't mention which radio was being interfered with, AM, FM VHF? Based upon which radio, a capacitor valvue can be selected to filter in that frequency range.

 

[Darrendude]

Re: radio interference with trolling motor

Thanks guys. Its and old trolling motor and the radio is an AM/FM/CD. It interferes even when Im playing a CD. The trolling motor , fish finder, and radio/cd are all run from my trolling batteries. I will try wiring the radio to the starting battery and see if that works.<br /><br />Thanks

 

[jlinder]

Re: radio interference with trolling motor

If you hear it even on a CD it is most probably getting in via the power line. Moving to the starting battery should cure it.

 

[chuckz]

Re: radio interference with trolling motor

Wow, that is broadband noise. The opposite of what I said is also true. When the brushes wear out there is a lot of arcing and a lot of noise. Check out the condition of the brushes in the trolling motor. Probably time to replace them and clean up the commutator. <br /><br />That much noise is not normal, it's telling you something is wrong. Fix the source of the problem. Otherwise I think you will be in the market for a new trolling motor real soon.