Lennart wrote: > > When I powered on my K2 today it shut down after a few seconds. The 2 > final transistors are warm but no power out. radio has been standing > without antenna or PS connected since last time I used it. Seems like > some bias level or driver is dead. Last couple of times I have used the > radio has been during tests of my new RS232 interface that worked very > well, but that is removed now during fault finding. > > Any tip on where to start looking? Serial no 6403. > > I vaguely remember (it was a long time ago) that I had a similar problem when building my K2. There is a component, an inductor I think, that provides negative feedback to the driver stage. It was O/C so the PA went into oscillation when the rig was powered up, and blew the driver transistor.
Why yours should suddenly go O/C after being OK I don't know, so it could well be something else. It could be failure of the device that switches the supply to the TX stages, so the TX side is getting power during RX when it shouldn't be. ----- Julian, G4ILO. K2 #392 K3 #222. http://www.g4ilo.com/ G4ILO's Shack http://www.ham-directory.com/ Ham Directory http://www.g4ilo.com/kcomm.html KComm for Elecraft K2 and K3 -- View this message in context: http://n2.nabble.com/K2-3-amps-on-receive-tp777708p777738.html Sent from the Elecraft mailing list archive at Nabble.com. _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
