[Elecraft] KPA100 Help PLEASE

[Lyle Johnson]

> I have completed the KPA100 upgrade but cannot get the K2 to recognize
> it. With a 20 amp supply connected I still get NO PA PS.


Check and verify that you have between about 3V and not more than 6V at U1
pin 7.  This senses the presence of the "12PA" source and is most likely
what the KPA100 CPU uses to verify there is a power supply attached and
working.  See Sheet 2 of the schematic,  in the upper left.  R8, Q12, RP1.
You should see about +12 on the 12PA side of R8, About +4 on the source and
drain of Q12, and about +12 on the gate of Q12.

73,

Lyle KK7P