Topic: Fishfinder interference

[bigbassbuck]

When I turn my 998 and 747 on at same time they both go nuts on depth up and down,they are going from like 4ft to 7ft for example,if I turn one off its fine,what can I do,the trolling motor has a built in transducer

[Humminbird_Greg]

Try setting the Noise Filter menu on each unit to a higher setting – or turn it on if it is not on yet.  You can also try manually setting the Lower Range menu on one unit to a different value than what is being used on the other unit.  Make sure that you are running the latest software as well.  If these don’t help than you will have to turn one unit off or turn the sonar in that unit off.

[justfishin]

A couple of things I have done to various boats over the years that helped are..

1. Run both units off the cranking battery. Not sure why this helps but it can at times.

2. Turn one of the units to the 83 kHz transducer band if both of them are on the 200 KHz.

James