(tr)uSDX Forum

I'm sure it was designed for 13.8vdc and it powers up on as little as 5v, but will the circuitry handle anything over 13.8vdc?

Thanks!
Steve/K7KWW

There´s a few parts in the Schematic, that would limit your max input Voltage.
Most prominent one is the 7805. Absolute max rating is 30V for that one, but Dissapation (wasting energy by heating up) because of big voltage drop increases extremely at higher input voltages.
Another one is the Class E Circuit itself, creating more and more power at higher input Voltages, up to the point of failure of the FETs.

So I decided to recommend min 7V and max 16V
But be careful at 16V.... It could already cost you the FETs when TXing into bad SWR.
On the other Side, I know a few people, that used it successfully with 4 Li Cells, but they did not tune their filters for 7W@12V before

73 Manuel; DL2MAN