K2: KPA100 fan issue + current question

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K2: KPA100 fan issue + current question

Jim KO5V
I just finished building and testing the KPA100 that goes with K2 #7225. This kit was a rev C, and I have brought it up to the latest specs. U1 says PA 1.1.

#1: It has passed all of the tests, except it apparently has no low fan speed. I have set the temperature of the heat sink using CAL tPA, after measuring it with an IR thermometer, and I have set and re-set the fan parameters in the secondary menu. On "nor" and on "LoHi" the fan is off. On "Hi" it runs. I have tested the amp's output into my power meter at 100w, but I haven't transmitted long enough to really heat anything up.

When I first applied power to the KPA100 for the initial tests, I believe the fan ran at low speed, so I have probably broken something...

#2: When I key the amp at 100w, through the power meter, and into a dummy load, I measure about .055v across R7, so that's ~11A. I expected higher current. Does that seem about right?

Any insight would be appreciated.

Thanks in advance, & 73,

Jim KO5V
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