[Elecraft] KPA100 Problem

[Harvey Howell]

Hello everyone. I almost made it to the finish line with my K2. I'm encountering a problem with the KPA100 SWR Bridge Null Adjustment (C1). I have everything hooked up correctly as far as I can determine. I set the power knob for 5.0 W. Enter tune mode and adjust C1 to get  1.0-1 SWR on the K2 display. The best I can achieve is 3.6w and  3.4-1 SWR. When the display reads this value my SX-200 power meter indicates about 18 watts out!! Also some of the voltages read a little high:

D13 cathode should be 90 to 150v : reads 158v.
U4 (MAX 1406) pin 8 should be -5 to -25v : reads -28v

Test Equipment Used: DL-1 and MFJ dummy loads.
                          SX-200 power meter.

I have given the board a close visual inspection and nothing looks bad. The red and green leads on T4 go to the correct pads. Any ideas? Thanks very much.

Harvey KN6VP
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