I started out, in 1982, with a Futaba 27MHz twin stick two channel, mostly because it was cheap and I was a poor E2 in the Navy. It went into my first two boats, then found its way onto a shelf where it still sits.
Radio number 2 is a Futaba 9CAP on 75MHz. It's a great radio, other than the fact that it's more of an aircraft radio. It's also sitting on the shelf waiting for me to get some planes built to put it in.
Radio number 3(and 4 for that matter) is the previously mentioned Futaba 4PLS. I still use it in my boat that I presently run and will be using it in the multiple boats I'm building.
As far as I know, no one makes a waterproof receiver. There are ways to increase water resistance however. Here are four ways, each with it's own benefits and issues:
- disassemble the receiver case and spray the circuit board down with Corrosion X and reassemble the receiver. DO NOT wipe off any excess from the board.
- without disassembling the receiver, fill the case with Corrosion X.
- coat the receiver circuit board with epoxy after removing it from the case, being sure to cover all component leads. After it cures, reassemble in the case
- stuff the receiver into a balloon after connecting the servos. Tie the balloon neck closed with a wire tie
As far as benefits and issues:
- Corrosion X isn't guaranteed to be water proof but can be removed if desired. It is, however, better than nothing
- epoxy will pretty much make your receiver water proof but it also makes sending it in for repairs impossible since there isn't any way to remove it without damaging the board
- balloons are not fully water tight and are susceptible to getting holes in them
Radio boxes have several ways for water to get into them:|
- through poorly fitted and glued seams
- through linkage or antenna holes
- through the box lid
Since you have electric boats, do you tape anything over the opening when you're running? Many of the guys I know have a thin piece of lexan they put over the opening into the hull and it's taped down to seal the boat against water. My boat is nitro powered so I only have the radio box sealed. It has a piece of clear plastic that sits on a lip inside the top that is taped down as well. Foam or rubber seals/gaskets just don't work. Where my rudder and throttle linkages come out of the box, I have rubber or rubber-like bellows seals like these:
https://www.towerhobbies.com/product...PRB286072.html
Hope this helps