Cretster

Hi all, I'm doing various different boat builds currently but have not had a proper functioning boat for years now.

I have several radio sets but after a test run of one of my fast boats on the sea resulted in a runaway last week (luckily I did eventually manage to retrieve without much damage), I'm now super paranoid about which of the radio gear I've got would be most suitable for ensuring this does not happen again, and for the most part, which of these is most likely to best cope with issues like reflected signal from the water surface etc.
For some reason the failsafe did not engage - no idea why.

Here are the contenders:

• Flysky NB4 Noble - I use this for all my fast cars and crawler trucks and I love this radio (BUT this is what I was using when my boat made a bid for freedom).
• Spektrum DX5E (DSMX) - currently I've only got park flyer receivers (Spektrum and Orange RX) but am awaiting 2 sets of AR6210 + satellite rx.
• Spektrum DX6i (DSM2) - same as above for receivers
• TBS Tango FPV radio (with FrSKY XJT JR tx module and FrSky S6R rx)

I've got various other cheaper car rtr ones like a taktic set, carisma set, acoms, hpi, and then some old Futaba 35mhz plane/heli radios (would not be keen on using crystal radios anyway).I don't know the definite cause of my runaway but the following things factor in potentially:

• Was using a mini receiver stupidly (has no exposed/external antenna wire, it's printed circuit inside the casing), BUT, the model was nearby when the runaway happened.
• Receiver was mounted too close to the motor so might have picked up interference
• One cell in the lipo died during the ill fated test run, not sure if this caused an electronic issue resulting in it losing control (but not deploying failsafe).
• It was suggested to me that it could have happened due to signal reflection off the sea surface, and to maybe try a different radio set. Spektrum DSM2/X is rumoured to have funtionality that helps prevent this, but I have no idea how the FrSKY XJT stuff compares?

A combination of potential causes as you see, and lessons were learned. Not sure I'll be able to identify for sure the actual runaway cause though.
So I'm looking for opinions on which of these is going to be the best option to use in my boat (and why) to give the best chance of preventing any future issues like this? Obviously a runaway is potentially super expensive but more worryinging a potentially dangerous issue even on the sea, and this is the first time I've had one since the old days of using crystal based sets when it would happen occasionally.

Thanks for all useful suggestions!

Cretster

OR, alternatively, if the answer really is "I wouldn't use any of those for use on the sea/water. It'd be a bad idea because XYZ, and instead you should buy a radio specifically intended for use on water", then please feel free to recommend me some systems renowned for reliable link and minimal chance of control loss on water?

For instance I've seen various comments searching other topics suggesting Futaba are decent for boats, and seen people recommending the 3PM radio, but when I looked that up I could only find that it said 100m range on it which doesn't seem very much at all!?

Thanks

Andy Yuen

what I've learn is that you can use nail polish to sort of coat on the electronics to use on water... not sure is it usable in sea water, you can try to use a 9g servo coat it with nail polish and submerge it and monitor...

Zeeb

My Feedback: (41)

2,4GHz band is NOT a very suitable band for water use. You'd be much better off going back to a 75MHz system.

Cretster

Thanks guys. Yeah I have got silicone conformal coating that I have applied directly to the circuit boards and their components of all my receivers etc now to make them at least in theory water resistant.
I don't think I've ever had a 75mhz set but I still have 35mhz plane and heli ones. I think in the UK here they used 40mhz for boats. I'm not keen on using crystal based radios though if I'm totally honest as runaways seemed more common with those as the crystals never seemed the most secure and reliable things, even when treated very carefully.

mongo

My Feedback: (15)

well, if yer dead set on 2.4,
ya need a diversity antenna system for the rx. at least 2 separated antennas. as much separation as possible and in a different axis.
axis 1 verticle
axis 2 horizontal widthwise
axis 3 horizontal lengthwise

i believe most reputable radio manufacturers sell extended antennas you can install.

Zeeb

My Feedback: (41)

Well the reason I said 75MHz is that is what is used in the USA for ground RC. The other frequencies you list would work better than 2.4GHz due to the fact that they are not line of site protocols, are nor susceptible to signal reflection issues found with the 2.4GHz frequencies from water. It's a much longer wave length and can go around hills and not be bothered by water reflections of transmitted signals.

Good luck on your quest.....