I wonder if Jukka remembered to re-tighten the screws holding the transistors to the heat sink after the first 10 hour "break in" period?
Doug W6JD -------------- Original message -------------- From: "Stephen W. Kercel" <[EMAIL PROTECTED]> > Fellow Elecrafters: > > I've had my K2 for only a short while, and I find that Jukka rises a > point that I've been wondering about. Can the K2 transmit at 100 > Watts (into low SWR) CW (say 20-30 wpm) in a continuous session for > tens of hours on end without damage? > > I usually use my rig in QRP mode, and only occasionally go to 100 W. > It always bothers me when the fan comes on even though I realize that > it is normal and desirable behavior. Thus far, I've only made one or > two extended "rag chew" QSOs where I've made long CW transmissions at > full power. > > Consequently, I have not much feel for how the rig should work while > transmitting CW at full power for extended periods of time. (As we > see from Jukka's post, running the rig until one smells smoke is not > a good idea.) What is a reasonable operational cycle? What is the > line between acceptable operation and abuse? > > Any insight from experienced K2 QRO operators would be most welcome. > > 73, > > Steve > AA4AK > > > > > At 04:21 AM 6/5/2006, Jukka Tarvainen wrote: > >Hello! > > > >Sunday afternoon my KPA100 started oscillating, I believe. It happened just > >when heavy rainshower hit our site. I was using a Spiderbeam on 20 meters > >and running small CW pileup with 100 watts. Rig was performing well for 18 > >hours on various bands and it was running quite hot. I put fan running high > >continuously in the beginning of contest. > > > >When this happened I disconnected power supply. K2 seem to work normally > >when KPA100 is not active. When KPA comes on it shows "Hi refl" immediately > >when transmitting and draws 20-30 amps from 30 amp power supply. Power > >supply starts to limit and cuts power. > > > >There was some smoke smell coming from K2. Can't see any blown away parts. > >Couple of 2 and 3 watts resistors have been warm, they are bit brownish. Any > >ideas what and where to start looking for? I built my K2 and options, but > >I'm technically challenged :) > > > >Jukka Tarvainen, OH4MFA > >K2/100 #4293 > >[EMAIL PROTECTED] > >http://personal.inet.fi/koti/oh4mfa > > > > > >_______________________________________________ > >Elecraft mailing list > >Post to: Elecraft@mailman.qth.net > >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 > > > _______________________________________________ > Elecraft mailing list > Post to: Elecraft@mailman.qth.net > 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 _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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
