DSM 300 Sounder - B117 Transducer Issue

[baja bum]

I have a customer with a DSM 300 (v4.20) driving a new B117 transducer which is mounted in a pocket on a Regulator 26FS. Following installation of the new transducer, the DSM 300 worked fine for several hours then lost bottom while showing a snowy screen on the C140W (v1.12) This same sounder works fine with a P79 transducer. I have tried two other DSM 300's with the same result. Is there any sort of issue with a DSM 300 when it is paired with a B117 transducer?

[Chuck - Raymarine - Moderator]

Baja [censored],

There are no known compatibility issues between the B117 transducer and the DSM300. The B117 and is plastic counterpart, the P319, have been installed on countless vessels without similar performance issues being reported. Also, as the 600W fishfinder performance characteristics of the B117 and and P79 are quite similar and the problem has been duplicated with two other DSMs, the fault appears to be rooted in the B117.

[baja bum]

Thanks. That is certainly one of the possibilities I am considering. What is unusual is that my EDI TT2D transducer tester indicates that the newly installed B117 is good. Another theory I am considering is that air has been trapped inside the recessed pocket where the B117 is installed. However, I have found no reports of this as a possible issue on Regulator boats.

[Chuck - Raymarine - Moderator]

You're welcome. You may want to try testing the sounder with another B117 slung over the side of the hull while the boat is drifting. Alternatively the second B117 may be tested after inserting into the P79's reservoir. Should the problem be duplicated with the second B117, then it would be recommended that the DSM300 be sent to Raymarine’s Product Repair Center to be bench tested with a B117.

[baja bum]

OK. Will do.

[Chuck - Raymarine - Moderator]

You're welcome.