Furuno 587 50khz Interfeance problems



I have a Furuno 587 with TM 260, Recently I had a Suzuki 140 installed and now I'm getting a heap of interference in 50Khz as soon as I start engine even in idle, Return is fine with engine off really doesn't help trying to find fish!! I've attached some pictures, where interference is blue I turned tvg down to medium experimenting. So far I've re wired power straight to battery, added ferrite cores to all cables and run power through a noise filter and that's it I'm out of ideas. Anyone had any similar issues or thoughts of what else I could try?

Thanks regards 



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Posts: 187

Date Joined: 19/08/13

hard one to work out

Sat, 2016-08-06 15:11

Check the connection where the lead from the TM260 connects into the mix and match cable going to the 587 I was told to seal it all up with tape and make sure it isnt near any other electrical connections.

Are all your spark plug leads in good condition, don't know how this would only happen using 50 khz though and be ok on 200 khz  

Posts: 574

Date Joined: 24/04/11

DC-DC isolator

Sat, 2016-08-06 15:50

 Not sure what sort of noise filter you are using, but if the problem is only when the motor is running, then you could consider a DC-DC isolator. This decouples any interference from the DC supply. It could also be a a vibration thing (although i've never heard of this). Maybe remove the transducer from the bracket and hold it over the edge while the motor is running.....

Posts: 8

Date Joined: 29/07/11

Hey guys, The transducer

Sat, 2016-08-06 16:08

Hey guys, 

The transducer doesn't have a mix match cable runs straight to head unit, motor is brand new so unsure of leads unless have dodgy one, 200khz reads fine until hit speeds over 20kn or 190m in depth starts to struggle there. Yeh I think next step is to pull transducer off as have noticed a little more vibrations with this motor and test maybe test another head unit.

Used the 10amp dc noise filter.

Feral's picture

Posts: 1508

Date Joined: 01/11/06

 Not sure how yours is all

Sat, 2016-08-06 20:39

 Not sure how yours is all wired up but dont have the sounder power or transducer cable running next to power wires heading up to your dash or throttle controls and see if that helps