Tips on troubleshooting sounder issues?

[jms02050]

I'm frequently losing depth readings.

In deep water I get frequent shallow water alarms as well as the depth reading just goes blank (appears as dash on my GPS). I'm also losing readings in shallow water as very slow speeds, so I don't think this is all caused by turbulence under the hull. Also noticed the water temp readings are incorrect as well (-1 F yesterday with water temps in the 50s).

My setup is a Raymarine DSM250 module and an Airmar B series transducer. These are tied to a Raymarine RL80C with an RL70C as a repeater.

Any tips on tracking down the gremlins in the system? I figured it's the transducer, but not quite sure where to start.

Thx.

[RobS]

You can contact Airmar for troubleshooting techniques. I did when I lost my temp reading. I was able to check the ducer and confirm it was ok and the problem was in the sounder.

The temperature reading sensor in the ducer is a thermistor. At 77deg F there is a resistance of 10,000ohms. The resistance increases as temp decreases. Mid 50's water should read a resistance of approx. 36,000ohms. With your VM set to OHMS connect the read lead from the meter to the brown Airmar wire, and the black lead to the white Airmar wire. You will need to get a pin configuration to know what Airmar wire color goes to what pin on the connector. On my Furuno ducer the white is 7 and brown is 4. Hope this helps...

[jms02050]

Wow!. Now that's a detailed tip. Rob, I'm thinking you've seen and fixed just about anything the forum presents. Thx!

[Serenity]

I had temP issues with my C-70. I went as far as order a new thru hull transducer. However when they told me I might require glass work around the old transducer I decided not to. Another ET advised me to just replace the temp unit in the transducer, crimp a couple of wires and I would be good to go. The total cost was half the cost of the new thru hull, which I sent back. The temp works great.

[jms02050]

Max, thank you for the tip. The sounder is on my to-do list...