[Elecraft] K3 Power Issues

[Keith Trinity WE6R]

Corky;
1. You can shove some probes (needles or something) into the Anderson's 
to check the voltage at the back of the radio.
Or pop the lid and measure at the circuit breaker terminal, but beware, 
this is always HOT even with the radio turned off!
We recommend 1/2 volt or less drop at 100W TX. (I have 13.8 to 13.7 drop 
at my bench with 2ft of heavy Motorola two-way wire).
1.(b) Measure the voltage at the 12V RCA out jack, this is after the Q2 
switch on the RF board that also powers the whole radio (other than the 
KPA3).
The RCA jack does have one protection diode in series however, (D34), 
not sure the voltage drop of that device.
Compare this with the above, maybe the 12V out has an issue. I have seen 
protection diode D35 drag down the voltage (or worse).
It is acceptable to just remove D35 because if it shorts (or partial), 
it can cook Q2 and possibly destroy the RF board!! (the resetting fuse 
does not protect for this).

2. If your P3 has the SVGA option and you are powering it from the K3, 
make sure you have the 1.0 Amp upgrade if an older rig.

3. Also check your "ADC REF" voltage fine-tuning, that will make the 
internal measurements more accurate.

4. Disabling the automatic TX gain cal @ 1.0milliwatt, 5.0 and 50watts 
in FW has not been implemented.
Keith WE6R K3/K4 Tech