I am using a Racerstar 35A 4 in 1 ESC, and only have the plugs wired between it and an Omnibus f4 V2 FC.  After maybe 10-15 seconds, the FC keeps rebooting.  I can't check the ESCs or motor direction or anything because by the time I get connected, it disconnects and reconnects every couple of seconds.  I am also testing the 5V pads and am getting the full battery voltage on them.  What's going on?

It could be a bad connection on the FC-to-ESC wiring harness. Try re-seating both connectors by unplugging and re-plugging them. And while they are out, use a magnifying glass to check inside the sockets for any bent or damaged pins.

Other than that it could be a bad 3.3V voltage regulator on the FC which is the regulator that powers the MCU. Use a magnifying class to for any stray solder balls, splatters of solder, or whiskers of wire on the board that might be causing an intermittent short circuit.

I'm not sure it's a bad connection - I re-seated both plugs and made sure they were in all the way and that the wires were snug and locked in. I went over everything looking for a stray wire or solder ball and everything checks out.

I've tried this now on two of the same flight controllers (both Omnibus f4, different versions) and it happens with both of them. Both also read the full battery voltage on the 5V pads as well - I tried hooking up an old Runcam Nano 2 last night and when I plugged in the camera got smoked.

I've had issues with these flight controllers in the past so I'm going to order an iFlight SucceX-E F4 MPU6000 FC and try hooking it up to that.

(09-Oct-2020, 02:25 PM)Eazy123 Wrote: I'm not sure it's a bad connection - I re-seated both plugs and made sure they were in all the way and that the wires were snug and locked in.  I went over everything looking for a stray wire or solder ball and everything checks out.

I've tried this now on two of the same flight controllers (both Omnibus f4, different versions) and it happens with both of them.  Both also read the full battery voltage on the 5V pads as well - I tried hooking up an old Runcam Nano 2 last night and when I plugged in the camera got smoked.  

I've had issues with these flight controllers in the past so I'm going to order an iFlight SucceX-E F4 MPU6000 FC and try hooking it up to that.

Try cleaning the plug with alcohol... it does sound liek a bad connection.

My phoner charge is securely snug as well, but it goes on and off because it's old and the connection is not solid. Poor design. Maybe oyou have another wire harness to try?

I ordered a different FC to arrive tomorrow - since there's clearly an issue with 5v regulation on both FC's, I don't think fixing the connector plug would solve much, even if it did fix the connection. But thanks for the idea!

(10-Oct-2020, 04:07 AM)Eazy123 Wrote: I ordered a different FC to arrive tomorrow - since there's clearly an issue with 5v regulation on both FC's, I don't think fixing the connector plug would solve much, even if it did fix the connection. But thanks for the idea!

Oh my bad I misread what you wrote... What I saw was "I checked the 5v and it gave full voltage"

 I thought you were saying they were good.

No, sorry - I wasn't exactly clear. Im getting whatever the lipo value is on the 5v. I'm never buying one of these omnibus boards again. That's 3 now that have gone bad.

which omnibus board was it?
i own one which does need 5v input voltage, probably this was your issue with them?

(10-Oct-2020, 02:55 PM)hugnosed_bat Wrote: which omnibus board was it?
i own one which does need 5v input voltage, probably this was your issue with them?

Flip32 f4 v2.

Snow Leopard helped me a few months ago with a v4 board that randomly blew a trace to the ram pads. I seem to have nothing but issues with these.

The clone Omnibus boards seem to be nothing but trouble and some of them are poorly manufactured. They also have some weird oddities with the way they do signal inversion. I would personally steer clear of any FCs that are Omnibus related unless they are an official Airbot manufactured board.

To all electronic guru, any help would be much appreciated.  I have a similar problem on my f4v3pro.  I must have damaged some components with the hot air gun.  The FC works perfectly when using USB power, so I know the 3v regulator is "fine".  However, as soon as I plug in the battery, either with or without USB, the FC would go into continuous reboot after around 10 seconds.

Maybe the 5v schottky diode is defective?  this is the component that regulate 5v from usb vs 5v from 5v regulator(battery).  Any other ideas?  THanks!