This reminds me of the IC706 (I think) which has a spike leading edge which shuts down an Alpha (which has protection circuits) but not a Heathkit for instance. Or is it just the power control itself which is faulty?
David G3UNA > > From: "Kamal Sirageldin" <[EMAIL PROTECTED]> > Date: 2008/09/25 Thu AM 03:35:12 BST > To: <elecraft@mailman.qth.net> > Subject: [Elecraft] K3 SSB Power Control and ALC Metering > > Michael, > > I also see the exact same symptoms you describe below. This is after > implementing Wayne's procedures 'to the letter.' Firmware V2.38, K3 S/N > 775. > > 73, > Kam N3KS > > Thanks for the detailed information. However, this is not my problem. > > The most severe problem I have is: > > a) the output power spikes and overshoots in CW or SSB or FM as you adjust > the power control, so it is not advisable to use a sensitive, i.e solid > state power amplifier with the K3. Especially not one needing less than 50W > of drive. It needs a fast responding meter to see it. > > A work around is to set the power without the amplifier in circuit, speak or > key to let the spike happen, then switch on the PA and not adjust power or > mode afterwards. > > Does this not happen to anyone else? > > A lesser problem is: > > b) that the power output is unstable once set in SSB mode, showing > variations of around 50-100% in the peak output depending on the power > output setting. This is when set up as described. It is only really visible > with a peak reading power meter. > > _______________________________________________ > 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 > ----------------------------------------- Email sent from www.virginmedia.com/email Virus-checked using McAfee(R) Software and scanned for spam _______________________________________________ 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