In the reply to Mike, VK1KCK I said "R1 is given as 50K preset. In the world outside the USA this would indeed equate to 47K" I found that this is not quite correct as although for carbon presets and controls have changed to the same decade values as fixed resistors in Europe at least, cermet presets which most probably Elecraft will be using for R1, still retain the older values such as in this case 50K for some reason. A visual check on my K2 is that R1 when set for 3.70V at U2B-5, being the optimum AGC threshold setting for my K2, the control is not far from half rotation, i.e. about 25K ohms. Working out the maths for the various resistors in series and parallel, including the RF gain control to form the potential divider from the 8A rail comes out fairly close to this voltage. The preset R1 is as shown in the K2 Control Board schematic, maximum resistance for fully CCW. Bob, G3VVT K2 #4168 _______________________________________________ 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
