Hi Ross; This looks exactly like the problem that I just recently experienced on #732. It turns out that one of the output FETS (Q5) in my LPA developed a gate to source short. Check the gate to ground resistance on each device which should be 1K-4K ohms. You should contact gary @ elecraft on instructions for a recent modification of the LPA to help with this issue.
I replaced Q5 and everything is almost back to normal but now I am working through another issue at this time. Russ, N3CO ________________________________ From: Ross Primrose N4RP <[email protected]> To: Elecraft Reflector <[email protected]> Sent: Sunday, March 13, 2011 9:33 AM Subject: [Elecraft] K3/10 low power output, fails TX calibration? My K3 #5143 has suddenly developed a low power output problem. Even with tune power set to 7W, it can only generate 3.5W or so on all bands except 40 & 80, where it can still produce 7W. Running the TX calibration in the K3 utility generates a failure when it starts as it can only do 3.7W on 160. Ideas? -- FCC Section 97.313(a) “At all times, an amateur station must use the minimum transmitter power necessary to carry out the desired communications.” ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] 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:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
