> But I am finishing my 300w HF amplifier kit and will be using a dc > open-frame relay for TR switching of RF. I guess I can time it using > my dual trace scope and set K3 TX DLY accordingly (amp will be keyed > with KEYOUT). I do not use CW very much on HF so QSK with 300w is > not necessary (or probably possible).
Even if you use PTT CW and set TX delay for 20 ms you will get choppy CW > There is one thing I do not see being addressed in this > discussion. Maybe more important than clipping of CW characters is > avoiding QRO "Hot Switching" of RF. Calculate the RF voltage for > several thousand ohms impedance (open circuit) that will result if > the amp is pumping out "globs" of RF before being connected to a good > load. The relay contacts will definitely get burned big time. And > maybe your output devices will have a short live-span. > > > 73, Ed - KL7UW, WD2XSH/45 The entire topic stems from the fact that I wanted to avoid hot switching of the external relays (linear amp, stack switching etc). To acheave that I have tried to increase TX delay and got choppy CW. So without external sequencer there is a choise between the two - 'hot switching' or 'choppy cw'. 73. Igor UA9CDC > ====================================== > BP40IQ 500 KHz - 10-GHz www.kl7uw.com > EME: 50-1.1kw?, 144-1.4kw, 432-QRT, 1296-?, 3400-? > DUBUS Magazine USA Rep dubus...@gmail.com > "Kits made by KL7UW" http://www.kl7uw.com/kits.htm > ====================================== > ______________________________________________________________ > 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
