Sounder interference

[cheno]

Has anyone had any experience with removing sounder interference.

My set up is as follows:
Lowrance x85 shooting through a Polycraft hull.
Power is a 60 hp 4 stroke yammy.

Cabling:
transducer passes on same side of boat as motor electrical cables but is not in the main bundle of cables that are in the conduit.
Sounder power cable is attached to bussbars that are used to power all electrics.

Description of interference:

Sorry I dont have a pic.

Vertical bars running through the picture at regular intervals that resemble fish show but continue through the bottom signal. These are not totally solid bars like I have seen on other set ups.

I am pretty sure that this is motor dependent interference (I have tried with and without the GPS etc) but I dont know how to get rid of it.

Was fishing the 36s off the seaway yesterday and the sounder had no worries picking the bottom and fish but the interference was a total pain.

Cheers

Cheno

[Kerry]

"shooting through a polycraft hull" is this a normal setup and is poly acceptable with shoot thru?

If all else fails then if it's possible hang the transducer over the side and see if there's any difference?

Cheers, Kerry.

[cheno]

Kerry the shoot thru part of it works fine.

My understanding is that Furuno has done some tests on this and reported no detectable signal loss.

The interference only is present with the motor running.

[Fordo]

Hi Cheno,
A couple of suggestions,
Make sure the power supply to the bus bar is coming from the battery as this should flatten any voltage ripple.

If you haven't already, also check on the sounder for a noise filter adjustment in one of the menu's, this might help but it can also effect your sonar returns.

Fordo

[ANYFISH]

guday mate
my lowrance sounder did the same thing when i turned on my electric motor. i got a small 12v battery similar to a motor bike battery and use it to run the sounder. it lasts for about 20 -30 hours of use and i just recharce it when i get home.

hope this helps

[cheno]

Fordo

I take it that you mean to check that the cables coming from the alternator do not have the opportunity to bypass the battery itself when the motor is running?

Come to think of it, although the buss bars are fed by dedicated cables from the battery, the connectors do overlap on the terminal posts. Pitty my battery does not have dual terminals like my last one.

BTW did you end up getting a new boat? I remember you stopping by to have a look at my old explorer

ANYFISH

Thanks mate I have a motor bike battery on hand that I could use if I can't fix the problem. Just gotta a place for it if need be.

[smerl]

Cheno,

Have you tried a 12V noise filter? Bias boating have the following which would probably do the job:

5 Amp Noise Filter Cat. 4844 BIAS $21.95
Suits most FishFinders, Radios, Stereos. 54mm long, 31mm diameter.

You just install this filter inline in the sounder power circuit. There is also a 20A option which may be big enough (should be) to install between your battery and busbar to protect all of your equipment from noise. I have a separate bus for the radios, GPS, and Sounder power which has a filter fitted.

It is better to install one of these filters in the power supply as teh filtering options on your sounder will actually just dampen the response time of the signal and cause a loss of resolution.

Cheers

Smerl

[Fordo]

Hi Cheno,

Hope you have your noise problems sorted, or are getting closer to a solution.

Bought a 4.5mt trailcraft profish a few weeks ago, so it took a while to find something.
Very Happy to be back on the water though.
Now down to planning the fishing trips again.

Hope your project boat goes well, when will you be finished?

Fordo