[Elecraft] high current with KXB3080

[Ron D'Eau Claire]

Rick, KL7CW, wrote

"... whenever I pried the LPF board slightly away from the main board
(1mm??) the 80 meter current dropped to a normal value and power on all
bands was OK.  I never identified the problem, but apparently something was
shorting with the LPF board snug against the main board.  With the LPF board
pried slightly away there is no problem.  I do not think it is a cold solder
joint since I can now tap the boards, wires, torroids, etc and nothing bad
happens.  Perhaps when installing the LPF board against the main board a
piece of tape or other insulation between the boards would prevent a
short..."

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There should be nothing to short to on the KX1 main board under the LPF1
board. There's only one solder pad under the LPF1 board. That is for the
inductor common lead from the LPF. (Originally it was one of the inductor
lead pads.) I wonder if you were shorting the inductor common lead to
something on the LPF1 board? It's a bare wire that has to bend over a bit to
reach the solder pad. Could it be pushed up against one of the solder pads
on the LPF1 and causing a short until you pull the LPF1 away from the KX1
slightly, which will straighten and move the inductor common lead slightly?

Ron AC7AC