A recent issue of B&W magazine had an article on using 2 Bottomline
fish finders at the same time to get a better idea of the position of
fish under the boat. The author supposedly interviewed Scott and Marty Glorvigan who are the guys who own the boat and the fishfinders.
They specifically stated that the units must be identical and operate
on the same frequency.
Now the Question....
I contacted both Bottomline and Garmen and asked about the
possibility of using two units at the same time like this and both
companies recommended against it due to interferance of one by the other. They said the two units should be operating on different
frequencies to avoid interferance.
Are they "pulling a fast one"?
Any comments?

If you are running two 'ducers that operate at the same or almost the same frequency, 192kHz/200kHz for example, you will have interference as soon as you're deep enough for their coverage zones (cones) to overlap.

I tried using 2 lowrance units, a LMS-240 and x-45 one is 192 and the other is 200 and they do at times interfer
either in deep water or when starting out or stopping

I have been told I could angle the transducers away from each other but I think that will give false depth readings and also mess up the fish arches

I could use some input on this subject too

rebs

What about Pinpoint gentlemen? They allow you to network front
and rear together. This is going to be my next step. Check out
their website. (http://www.pinpointfishing.com/)

Brian

You are correct BigZees2, I think you have to special wire or network them together.

A nice innovation, especially if you like Pinpoint 'finders...I guess ONLY if you like Pinpoint.

I've been running a Hummer Paramount 3D in union with a Lowrance X-75. The Hummer operates at 455kHz and the X-75 at 192kHz. No interference.