Well, after checking that all of the components in the fan circuit were correct, I decided to follow Don's usual advice about checking my soldering, so I re-flowed all of their joints. None looked bad, but now the fan works as it should, so...
I'm still curious about my 11A @ 100W measurement. I think I'll borrow a friend's DMM and see if I get the same voltage measurement across R1 (unless 11A is in the ballpark). 73, Jim KO5V -----Forwarded Message----- >From: Jim KO5V <k...@earthlink.net> >Sent: Nov 8, 2018 2:11 PM >To: Elecraft List <elecraft@mailman.qth.net> >Subject: K2: KPA100 fan issue + current question > >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 ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
