Mike, You most likely do have a thermistor board problem - a short from pin 2(and 3) to ground (pins 4 and 5) could cause the situation you describe - in that case, the op amp would be producing full output with any voltage input above zero volts.
73, Don W3FPR > -----Original Message----- > > My K2, #5943, is having a bit of an issue. I've just finished the last > construction stage (except for final assembly) and have yet to do the > final alignment. The issue is, I've got a problem somewhere around U6 on > the RF board. During CAL PLL, its input from U5 decreases steadily in > voltage, as it should, except its output remains at a constant 8 VDC. > During normal use, the VFO display acts normal but I can effectively > only tune in approx. 5 KHz intervals, due to how the K2's fine tuning > works. Examining the board did not show any shorts anywhere around U6 or > on the thermistor board. Any ideas? > -- > 73, Mike > KCØTQX > -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.446 / Virus Database: 268.18.4/703 - Release Date: 2/26/2007 2:56 PM _______________________________________________ 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
