Mystery objects - anyone recognise this?

[Ardenfour]

I,m getting very erratic depth readings from the sounder NASA Clipper - mostly displays 'OUT' but occasionally jumping numbers and sometimes an actual depth. Been tracing wiring and came acrossobject in pictures. There are two of them, p + s, and two of the connection boxes. They seem to lead to a third box containing a mercury tilt switch, and then to the display head. But I also have a third transducer with coax going to it, original to the boat, encased in grp. Any ideas? I've fitted a new coax plug at the display end, the old one was a tv coax and the core and braid were shorting.View attachment 52671View attachment 52670

 

[prv]

There used to be a vogue for fitting a log transducer on each side of the boat, and automatically selecting the leeward one for each tack via a tilt switch. The idea being increased accuracy away from the surface turbulence. I've even seen the wiring for this on a 600 ton sailing ship, though the switch had been bypassed to run one transducer all the time. Not uncommon, I suspect.

No doubt that's what's going on here.

Pete

 

[Ardenfour]

cheers pete. Nothing to do with sounder then. Will look again but i'm pretty sure the output from the tilt switch goes to the sounder

 

[prv]

cheers pete. Nothing to do with sounder then. Will look again but i'm pretty sure the output from the tilt switch goes to the sounder

I suppose the same principle could be applied to a sounder. But the transducer device, though it looks like nothing I've ever seen before, seems more like a log than a sounder. It seems to be removable, and/or retractable without removing, which makes sense for cleaning a paddle-wheel but is irrelevant to a sounder.

The box in the second picture clearly says "log" and "speed".

Pete