[yashuone]

While flying today testing some new expo settings I was doing some multi rotation rolls and one went awry at low altitude and we suffered a mild bounce off the ground. It's pretty cold out and I didn't even suffer a broken prop just to give an idea that the impact was mild. I flipped the quad back upright but then had no response when attempting to re-arm. A quick visual check showed no lights on the rx so I headed back home to the bench.

At home I discovered that the only illuminated LEDs were on the PDB. No power to the FC however the accessory LED board I have is still powered and it draws power from one of the free channels on my CC3D Atom. So there is power at the pins but no illumination of the FC LEDs.

At this point I plug into GCS and the board wakes up and appears normal. Power to the FC returns, Blue and green LEDs are illuminated and displaying the expected pattern of flashes and GCS is recognizing the board.

I am running iBus on an FS-iA6B plugged into the Flexi-port so the rx draws power from there normally however it appears that if the FC is not powered I am getting no voltage at the Flexi-port even when connected to battery power. I have checked for voltage at the BEC on the PDB, also at the pins on the FC and it shows normal.

In summery; upon battery connection I have 5V at BEC and all six channel pins on the board and 0V at ports and the FC is not powered (no LED). Upon USB connection I have power to the FC and FC checks out normal in GCS.

Ideas???

[TheOtherCliff]

There is a diode that does exactly that.  It or the traces to it are probably damaged / gone.

If you can solder very very tiny stuff, you could fix it correctly by repairing / replacing, or hack it by just running a wire from here to there (short out the diode).  Or you could buy a new CC3D for about $8 shipped (the full sized version) on eBay.

[yashuone]

Well that's unfortunate... thank you for the heads up T.O.Cliff, once again bringing light to foggy, black magic world of the CC3D FC. I think I'll just order another board. Perhaps in the meantime I'll mess around with this board and hone my soldering abilities 😄

[yashuone]

On a now related note, are the STM32F405 chipped Revolution knock offs seen on EBay worth getting? I am finding them for about $20 from China and $25 from domestic warehouses. It would be nice to have some of the Revolution upgrades without suffering the $40 to $80 price tag. Just not sure if these boards are junk or not.

[TheOtherCliff]

Cheapest Revos I see on eBay are about $34 shipped.

Some stuff I have bought and tested... other stuff may be OK but I don't know.

I have bought some Sparky2's from xt-xinte.com for about $38 shipped but they require some fairly easy soldering and some solder removal with a knife.
http://www.xt-xinte.com/F16821.html

I have bought some Sparky2's from this eBay seller for $46 shipped.  He appears to be clearancing the official (black) Sparky2's that are no longer sold officially.  For Sparky2's, I recommend these because they work out of the box.
http://www.ebay.com/itm/172353561802

I haven't bought a Revo in a while, but the Nano's from here are legit and work for $30 shipped.  It appears they are also clearance of the official OP Nanos that are no longer for sale officially.  Shipping price drastically increases if you buy anything else.
https://sasquatchlabs.org/product/genuine-nano-flight-controller-w-case/ (sasquatchlabs.org web store has closed)

If you eventually want GPS flight or baro controlled altitude or telemetry or AutoTune then a Revo or Sparky2 is what you need.  Nano is the same but doesn't have built in telemetry.

[yashuone]

Thanx for the info. I already picked up another CC3D but I might pick up the "nano" you posted up there. Seems like a good deal and while telemetry is not a huge factor for me at the moment I have been wanting to take advantage of the auto-tune capabilities.