A few days ago, I somehow managed to fry something on my Axe CP. I was putting the canopy on when the tail motor spun up (it's got a GY240 gyro on) and I carelessly flicked the rudder over, accidentally giving it a bit of throttle at the same time. My other hand happened to be reaching through the rotors at the time and so the motor stalled/failed, and suddenly it seemed the heli was getting no power at all -- not to the receiver/servos, engine, etc.

I took it apart and found that I've got at the least a broken receiver and a non-functioning servo. Well, I have a spare Electron 6 receiver lying around, along with an HS-55, and I figured I'd take advantage of this upgrade opportunity to get the heli to run on my eclipse 7 radio instead.

Well, I wired it all up and with the receiver and servos plugged in, everything works like a dream. Programming the Eclipse was a little daunting but I'm happy with the result. I tested out the gyro and tail motor, works perfectly. I plug in the 3-in-1 board (which I'm essentially using as just an ESC for the main motor now, having done the GY240 upgrade) and ... no main motor?!? I've double-checked everything I can and I'm reasonably sure it's wired correctly, except for a small unusual thing.

In the Heli-Max upgrade, the C-12 ESC's BEC is disabled since the 3n1 board provides the juice. However, setting it up this way again results in the servos going whacko (extreme jittering) over which I have no control. I re-enabled the C-12 BEC and took the red wire out of the 3in1 board's connector, and the servos and everything else works -- just not the main motor.

I was wondering if this could be a setting on my transmitter (somehow enabled throttle hold? As far as I can tell, it's off) or a damaged/destroyed 3in1 board? Should I just purchase a new ESC for the main motor?

Any ideas are welcome

Sounds like you got your 3-in-1 a little too hot. Time for a new Main ESC ( and maybe an upgrade to brushledd main motor) to replace the 3-in-1.


Splat

I thought that might've been it, but I dearly hoped it wasn't What kind of amp rating will the ESC need to support? And I think I'll stick with the regular 'ol brushed ESC for now, I'm still a beginner and there's plenty of time to break things

20A to 25A or there abouts =) It's better to go a little heavier than to go too light. The stock motor can draw over 20A in a full stall, so if the ESC doesn't have current limiting, then you are going to want to figure out the max draw the motor would have in a full stall. If the resistance is 0.6ohms your max draw is 21A on a fully charged 3s lipo