Hello all,

Just wondering. Do you all have your trolling motor and fish finders hooked up to the same battery? I wired two new fish finders onto my boat and now it seems like ever time i run the trolling motor I get interference on my fish finders. I put a second battery on the boat and it seemed to correct the problem but I don't like the extra weight. Do you think I could wire one for the cranking battery and put the trolling motor on the same one? Any suggestions.....hope I didn't confuse anyone!!

Trolling motors use a lot of power and in create a lot of noise on the battery. This has often cause interference on my FF. I have 2 boats, both have the same problem. I improved the small boat by putting an L/C filter in the battery power line. I think almost any filter will help, just be sure it has an inductor (L) and a capacitor © in it and it can handle 1 amp of current.

The larger boat is used on the ocean and I am often in hundreds of feet of water. My Raytheon unit was about useless when moving along at speed, and unreliable at 5 mph. I installed a small motorcycle battery and use it just to power the FF. I also disconnected the FF Negative lead from the motor ground. Great performance now and I can use it at 20 mph with no problems. The small battery will run the FF for several weeks and I take it off the boat to recharge it . My FF only draws .05 amps so it doesn't use much battery.

This is what I run my fishfinder off of:

I was having the same problem and I didn't like the weight of 2 deep cycles in the small pond hopper Jon boat.

Panasonic LC-R127R2P1  I can run the fishfinder and portable bubble maker off this battery for 10 to 12 hours before I have to recharge.

Panasonic LC-R127R2P1 (12 Volt/7.2 Amp Hour) Sealed Lead Acid Battery - 0.250 Terminal - VRLA (AGM) Technology

Weight about 5 pounds.  I have two of these that I take out with me fishing.  Mine came out of APC Power supplies.  But they can be had for around 24 dollars

I wouldn't wire it up to the starting battery. My dad's boat was set up this way when he bought it and every time you would start the motor it would turn off the DF. I am running itno the same problem with mine. I run a 36 volt tm and the Df gets its power from the 12 volt side of the setup and both share the same ground. my problem is weird. It will interfer only when the TM is running at a slow speed (whitch is what it is run at 99% of the time). but when I ramp the power up past 50% the interference goes away. I think I will try the filter, if that dosen't work I will have to rewire it to another battery