K2 Help Troubleshooting a dead short on RF board

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K2 Help Troubleshooting a dead short on RF board

dw-4
Is there a particular component on the RF PCB that would fail and give a
dead short from 12V to Ground?

I'm wondering what component(s) you might look at first?

I had the K2 cover off the other night.
The unit was turned off and the power supply turned off.

I attempted to solder a 2n7000 circuit to the 8R line for an external
T-R switch.
But I neglected to unplug the power supply even though it was turned
off.

I'm guessing some kind of surge hit a component.
Now I'm looking at the RF board to see if I can single out the area
where the short is.
With a digi-ohm meter I get almost zero ohms from 12+ to ground.
The F1 Fuse appears to be fine.
And I lifted one side of the D10 (reverse polarity safety diode) so that
is not the problem.
I've pulled the IO controller PIC from the board and the short is still
there.
Also all other PCBs removed.

I wonder if I killed a fet?
I'm thinking about lifting a couple of the RFC-chokes as a way of
isolating the different areas.

Any suggestions would be very helpful.
Sincere Thanks!
N1BBR
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