Vic The bandpass filter alignment merely assures you have adequate drive to the PA. The LPF will have more effect on the PA current, as it determines whether you have a match between the load the and PA. 73, Bob N6WG
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Vic Rosenthal Sent: Sunday, May 15, 2005 3:39 PM To: Elecraft Reflector Cc: Gary Surrency Subject: [Elecraft] K2 current draw I just noticed an interesting thing about my K2/100: the current drawn by the low-power part of the K2 (that's the current measured when you tap DISPLAY) is extra high on one band: 20 meters. When I'm running 100 watts out, the current displayed varies from about 2.2-2.8 amps on all bands other than 20. On 20, it's 3.5 amps. My first thought was that the bandpass filter was misaligned on 20. Sure enough, after adjusting L7 and L8 on 30 meters, the 20-meter trimmers were at minimum capacity when the output peaked. I had to add an 8 pf capacitor across one of them and a 27 pf capacitor (!) across the other in order to have the peak fall in the adjustment range of the trimmer. Very suspicious. After doing this, I verified that the current draw when running 10 watts on 20 meters was in line with the other bands. But when running 100 watts, I still get 3.5 amps! Something funny is going on. Why was I unable to get a peak on 20 without extra capacity across the bandpass filter trimmers? And why is the current drawn at 10 watts normal, but high at 100 watts? This is not something new, I've just ignored it until now! -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco _______________________________________________ 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 _______________________________________________ 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
