VH06S,
It appears that the M-174 is an older Airmar 1Kw transducer that has is no longer in production. The information I found via a Google search says it is an in-hull transducer with a 10-pin plug? Airmar's website doesn't provide any additional information if the transducer uses two or four wires. Sorry without additional information I have hit a dead end.
Snips