Greetings from a newbie K2 builder. I am currently building #5390. Into phase 3 now, somewhere in the early stage of the rf board. Don't get too much time for this detailed work and my xyl has made me clear out the spare bedroom in our apartment (aka construction area), as she does not seem to like the lead droppings and other bits and pieces on the floor, while one of our daughters and young toddler are visiting.
While the build is only a work in progress, and although it passed the stage 1 and stage 2 tests it's not over till it's over, my mind is turning to the question how to exploit the K2 when it finally gets launched. Let me say, I have nothing against qrp. The main reason I bought the kit (instead of an Argo V), was the desire to have a low current drain rig, to take on /P. I don't have much of an antenna sytem at this VR2 location. I have a Icom IC-781 which serves as the main rig at this station, but if the K2 works, I would like to try it as a main station rig with decent power as well as a /P rig. Here's the question. My only amp at this location is a Drale L4. It is just a 10db gain amp. So it would only produce at most, 150 watts driven by the K2. In practice, probably less. I have never driven a grounded grid triode amp sccessfully with such low power with any success. How does one drive a 10-15 watt output radio to serious output without an intermediate amp? I have designed and built many amps and repaired many others but not before an amp with a projected power gain of 20db. They were all either grounded grid triode affairs or a G2DAF (pair of 813), which is pretty similar. My basic thinking is a high mu tetrode amp, grid driven, preferably with a swamp resistor as input but, if needed, a tuned input and neutralized. I love glass tubes and am shy of using a 4cX400a or 4cx800a type tube, as I hated my ex-Alpha 01b, although I think the tubes would probably work ok but uninspiringly with the right design. I would really like to try a 4-1000a or even a 4-400a in that configuration. I have no issues with working on high voltage and plan to use the 2.5kv supply from the L4, though the 4-1000a does benefit from a higher anode voltage if available. I would be interested to hear from anyone else who has gone down this road and of their experiences. Meanwhile, best 73s and GL to you all from Hong Kong. Wyn VR2AX (ex VS6UK) GW3YGH _______________________________________________ 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
