I notice hobby-shop RC kits look insulated to withstand experimentation. Is a voltage regulator at $40 still almost mandatory, though, or can a $50 receiver board be pretty tough ? I'd be glad to hear recommendations for brands and models for the rig-development phase (and hopefully fitting a 2" inside-diameter cylinder).



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My track record with electronics on this project:

All the following boards were taken from cheap, sacrificial R/C cars--new, two channels each. Aside from on/off switches, which I forget to test, I've tested every switch position of every board and transmitter before lobotomizing the car.

Initial purchase--two 4-AA cell R/C car boards, $13 each. Experimented a lot and found I couldn't work the tiny filament wires through the board, eventually ruined every channel: My soldering iron is battery-powered and I kept trying to solder with low batteries--dropped copper rings off them. Started substituting my own, thicker wire which is more workable.

boards 3 and 4: 6-AA boards, $15 each, got response for a while during development, experimented and eventually ruined the same way.

5: 6-AA cell for $15. Knew what I wanted by this time; after water exposure, it still tested OK, but maybe waterlogging caused a voltage spike later as I fiddled with it, so its power circuit is dead now also.

6: 6-AA for $15. Thought I would get crafty using a fine drill bit to open lead holes in the board, possibly then just hitching bent unsoldered leads into the board (the possibility that voltage spikes were killing hadn't yet occurrred to me).

How #6 died is a mystery to me, but I hypothesize I loosened or perforated a conductor strip or ring with drill vibration. After removing it from the car and giving the board my cleanest, best-looking soldering job yet, I never got a milisecond's worth of response from this board mounted in the sub.