The pin diode bias supply is 270dc. That is what is failing. Has nothing to do with your mains. Generally you should look at the last thing(s) you did before it failed. That is where you opened it up and did something. How did you determine that the HV was ok as is? Unplug anything...inadvertently...? Take a look where you were inside. Something with the interlock micro switch?
Chuck Hawley c-haw...@illinois.edu Amateur Radio, KE9UW ________________________________ From: elecraft-boun...@mailman.qth.net <elecraft-boun...@mailman.qth.net> on behalf of Mike Streeter via Elecraft <elecraft@mailman.qth.net> Sent: Tuesday, April 30, 2019 2:52 PM To: Elecraft Reflector Subject: [Elecraft] Fw: KPA 500 HV Problem. ----- Forwarded Message ----- From: Mike Streeter <wm...@yahoo.com>To: elecraft@mailman.qth.net <elecraft@mailman.qth.net>Sent: Tuesday, April 30, 2019 02:50:12 PM CDTSubject: KPA 500 HV Problem. My KPA 500 has been running ok for several years on 120 Volts. Today I turned it off on the back , unplugged it and opened the top because I thought I might need to change the voltage tap. I did not need to change it. I replaced the top cover, plugged it in and turned it on at the back. All ok, but when I turned it on with the front panel button the HV reads .1 in standby. If I tap OPER it shows a hard fault and "270V error" .The Manual says this is a 270V supply failure and to recycle the mains power KPA 500 after it is corrected. I tried recycling the power but still faults. I don't have any 270V power from the mains, if I did it would be 240ish, not 270. The fuse block on the back is set to 115V.Any advice would be welcome.Mike, WM5DX. ______________________________________________________________ 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 ______________________________________________________________ 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
