The most common US manufacturer is AirMar. It is common on modern
recreational type boats for dual frequency transducers running at 50 and/or
200 KHz to be installed. A lot of them also have Hall Effect speed sensors
and a temperature sensor, hence are called dual frequency Tri-ducers. AirMar
makes them as the OEM for Raymarine, Furuno, etc. If you have any numbers
you can find on the cable, etc., I may be able to cross them to an AirMar
equivalent and then give you the specifications and pin out.
Doug K7ABX
"Bruce in Alaska" wrote in message
...
In article 7y%Mb.83359$X%5.9293@pd7tw2no, "Henry" wrote:

Modern depth sounders work at 200K. This is radio frequency.

Well, maybe, but not for sure. Common sounder Frequencies a

50 Khz
88 Khz
100 Khz
200 Khz

Most of the consumer type sounders are 200Khz, that is true,
but there are a whole slew of different types and they use different
frequencies, depending on the typical use.

Bruce in alaska
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