Anyone have a problem with transom mount transducers?

[juniorg]

I have the raymarine dragonfly fish finder combo with chirp and a transom mount transducer. I also have a garmin smartduser transom mount that ties into my nema 2000 network to give my garmin chart a depth reading because my dragonfly isn't nema 2000 The boat dealer has adjusted the transducers but still not consistent sometimes they work perfect sometimes they read 0 or false readings. Both at different times and sometimes together. I shut one downt to check if they were interfering with each other and same results.

 

[POGE]

Where are they mounted ?
Do they work if the boat is just floating still Vs. running?
working and not working, seems like a install issue from just guessing.
On my DV and have 2 units both mounted on the flat part before the chine, second one in from outer hull.
I have one set at 50Khz and one at 200Khz. They work fine, bottom paint does not effect them, but barnacle growth can.

 

[juniorg]

One is mounted on the left and one on the right about 8" in from the trim tabs. The dealer mounted them in the right places I am being told. They work perfect not moving. And sometimes perfect for the whole ride. Then sometimes they just misread and one will read bottom then the other won't and ..... The raymarine is a chirp I thought that they possibly were bouncing frequencys off each other but turning one or the other off doesn't change it. Originally it would lose reading when I trimmed the boat up. So we pulled it out and adjusted the transducer angle. Now I'm getting the inconsistency still.