Unit dead


Another clue, when unit is powered successfully the 5 volt regulator on the raduino gets quite warm. You can affirm its action by checking to see that there is 5 volts on the board.

With my v4 it is visually easy to plug the raduino into the board and be off by one pin.

If a tiny piece of wire is shorting something, a good power supply may stop outputting voltage then.

The need to debug is part of the journey. My v4 is on the bench because one of my mods isn't properly installed, even though it is working nicely on transmit. Debug time, I will find it.


Evan Hand

A quick check for the Raduino is to pull it from the main board, connect a miniUSB cable to the Nano (socket is between the Nano board and the Raduino board) and supply a standard 5v USB power to the USB cord.  If the display lights, and the operation of the Raduino seems normal, then the problem is on the main board.

If the Raduino display will not light, then it is possible that the problem is the 5vdc regulator failed on overvoltage.  Only what that I know would be to remove from the board and try USB power again.

What test equipment do you have access to?  Since you reported voltage and continuity measurements I would assume at least a multi meter or DVM.




Short of seeing visible burn damage in both rig and power supply, let's hope its something else. Use a dvm in ohmmeter setting to do a continuity setting, no voltage applied.  first check for a direct short. Then move to using the schematic to see if there is connections from 12 volt input to the board, and places where it should be. Mistrust your own wiring, and I hope you find something.

Separately check that power supply, that you may have to plug in.

It has to be something. With no burn or fireworks,  lets look for a connection problem.



Don't know if it's related, but my power supply died and now the unit is also dead.  I wasn't sure if it hurt to have the power supply on when the transceiver is off and I forgot to pull the plug, but the other day all I got from it was a faint flicker on the power supply light, no output.  Perhaps a surge wiped it out.  I got another power supply and it measures 12 volts output, but no response at all from the Ubitx5, no sound, no display, nothing.  I've checked the connections and don't see anything obvious.  The fuse tests OK with ohm meter.  The power switch seems OK.  The 2 cables from the big board to the small board are firmly seated.  I've jiggled wires and played with it but it's not resuscitating.  Any suggestions?