"capt-dia" wrote in message
oups.com...
I am about to purchase a depth sounder to replace the old one[s]. I
have two transponders in the bottom. One at 50hz from a Furuno/Kobel
and another 200hz (???) that belonged to a Gemtronics. What are the
chances that they will work with a new sender/display unit.

Making a couple of assumptions here, one that the two transducers in
your hull are still in good shape, and the second that you are not trying to
run more power to those transducers than they are capable of handling, then
chances are pretty good that they will operate fairly well.
Just how well will depend on the transducer matching network on the new
machine and the type of transducer cable on the old transducers. Cables with
a shielded, twisted pair of wires will adapt to many current machines (200
or 50 Khz, of course) but if the cable is a simple coax cable the matching
is not so likely.
While in the "business" for many years, we always advised the new
machine owner to be sure and anticipate transducer changes may be necessary,
but it is worth a try to use the old transducer. The Konel/Furuno
transducers were normally pretty high quality, and stand a small chance of
performing better than the transducer provided with the new machine.
Bottom line: It's sure worth a try!

Old Chief Lynn...... been there, done that.