What radio are you running?

Perhaps, I am sending them to Nomadio for repair, so it will probably be less than $100 each. That is just the replacement cost.

The Sensor.

The only thing I came up with last night is that the MGM was trying to power everything through the receiver plug, pulled too much current, and poof. But the question is why?

If the ESC's BEC output voltage is higher than the UBEC voltage, the current will come from the ESC BEC and the UBEC won't do anything.

Once again, this is an opto controller, no internal BEC.

The real shame of it is that the Compro looks like such a bad a$$ controller and it's appears to be built well. I feel for you. It sucks to have problems like this with a piece of electronics that is on the pricey side.

Sorry, I guess I missed the first time you said that. My bad.

Question: What exactly does opto-isolation mean for R/C? I know what it means in the electronics world, but am having a hard time firguring out how it relates to BEC use...

No problem at all and I appreciate your trying to suggest an answer. I just wanted to re-post it for clarity's sake.

As for the second part, I don't have a clue. I'm still trying to figure out this mystery before I do any more figuring.

OK, where are the mods! I now need to know how opto-coupling applies to R/C!

However the BEC is coupled, it seems odd that the receiver is fine until you hook the MGM to it (if I read the problem correctly). It just sounds like the receiver is getting more voltage (somehow) than it can handle and blows up.

try this, just for trouble shooting. Measure the voltage at the receiver, maybe use some small wire to hook up in the there. Then use a multimeter on that, just don't let the wires touch!! :026:

My Sensor read a constant 5.57-5.58 for receiver voltage with the ubec. It has never been wrong (I love this radio). Just for giggles, I hooked up a receiver pack and got a reading of 6.78on the display. I then took a multimeter to the pack and got a reading of 6.82.

Well, something has to be killing your receivers. I don't know how often the radio samples the voltage which it simply isn't picking up, maybe there are spikes of voltage. Although I can't imagine why...

Let me help you out:

Opto Isolation as relating to R/C is the same OI as in all other electronics pertaining to OI. OI allows a low voltage/power circuit to control a much higher voltage/power circuit. Your Opto-ESC contains two basic parts, the Control side and the Power side. Between the two sides are three OI Semi-Conductors. Three because the ESC has three phases, usually. Each OI SC contains an Infrared LED and an Infrared Phototransistor. The Control side of the Opto-ESC simply turns on each IR LED in sequence, which turns on each IR PT in sequence, which activates each phase of the Power side, yes, in sequence. There is absolutely no hard-wired connection between the Control side and the Power side of the Opto-ESC thus you need a reciever pack to supply power to the Control side of the Opto-ESC as well as the reciever and servos.

Thank you. That does not have anything to do with the BEC circuit though! I then take it OI has nothing to do with the BEC...