@jph it's the On/Off switch, and I've called a couple of those places and no one seems to be able to have that switch for the older GA-52, not even Sc...

Not sure how to take that comment ???? Enjoy!

@brad-ott the specs can be found

@brad-ott Brad, the X3 & X4 measure the slope distance and angle to the shot, calculates the vertical (side b) and displays the lengths a, b &...

I tried several of the units mentioned, but ended up buying the Leica Disto X4 ($376 on Amazon). It measures the angle and slope and reports the calcu...

@amfromnome That's an impressive setup. Any chance you could share your parts list, especially the echo sounder and connection details? Thanks!

Thanks for the recommendations-greatly appreciated!

@martin_au thanks Martin!

@mark-mayer Great! Thanks Mark!

@learner -thanks! That particular unit is out of stock, but I would imagine any in that class would do the job.

Sounds good-thanks!

Thanks for the reply and pics. Would you know what brand/model your single beam sonar is?

Many thanks for the replies!

Ranger 500X SP4.7.1 Robotics & GPS * SOLD!!!Thanks!