How to electrically release a buoy ?

[USNMARS]

when we do something like that then use a 20ft section of rope tied to the platform with a small weight at the other end. Stretch the rope out and drop the weight., mark GPS locations. When you come back to recover the equipment just start tossing a hook with a rope around and snag the tagline you layed out. Catch the rope with the hook, and pull everything up.

 

[lowviz]

...//... I would be discreet with the final design, a remote deployed bouy and a remote deployed tethered mine are very similar in basic design.

You share my concerns.

I have experience designing highly reliable electronic systems. It would comfort me if the OP would pony up as to the exact intent.

DTMF is proven and easy. Cheap. Ultra low battery drain receivers. So, if you are looking for any one frequency with a scalable gain receiver, you will find it. Probably a passing boat. Looking for two distinct (much higher than background) tones will provide a tremendous increase in reliability.

This is fun too: