Hi Tom, just would like to thank You very much for Your (and Nigel's) very valuable information You have put on Your web site.
I stumbled on the birdies on 160/80 some time ago on a fieldday and was thinking about looking into the circuits one day. But the birdies are just S3-5 here. Just to add a few notes: I added a hard DC connection from the negative output to chassis/ground. This was done because modern 12 V rigs do not have any chassis ground connection when using symmetrical antennas (dipoles) and those ground isolated PS. This makes the rig chassis and coax braid eventually floating on unknown voltages. I observed this on several field setups, especially when using vertical antennas. The protective ground of Your mains may not be a good RF grounding, though. But it prevents static charge up of Your chassis (and the "connected" operator) via the coax braid. I also added a surge arrestor to the 13.8 V output of the PS. One day on the field there was a thunderstorm around, but it was still some miles distant. But a surge came via the mains line killing not the Samlex PS but the TR switch in my K2! Fieldday over. The only destroyed part was the 1500 V rated ZVN4424A! Ouch. After christmas I will add the ferrite beads ... Have a good time. VY 73 de Marcus, DL1EKC _______________________________________________ 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