Working on my 2nd K2 (S/N 7869) and have run into a problem with the VCO alignment. I'm getting a constant 8.37 V at R30 at 4.000 MHz.. I cannot change it with the full range of L30. Correct type inductor is installed at L30. Dropping the VFO down to 3.500 doesn't change it either. I have gone back through the archives and read just about every post concerning this problem but nothing I have tried has made any difference. I have double checked all correct parts placements and orientations, re-flowed all connections in the quadrant of the board around the VCO section. T5 is wound as per the manual (from the Toroid Guy) and installed correctly. I have tried both spreading and compressing the turns on T5 with no change either way.
Regarding the thermistor board, I have 4.18 V on pin 5 of U6. Test in the previous section were within specs: 4 MHz Oscillator Cal using CAL FCTR was 12099.61 and confirmed with an external counter. Range of the PLL reference oscillator: 12099.61 - 12086.01 = 13.59 kHz VCO oscillator test: 8162.60 MHz I'm about out of ideas at this point. What should I start checking next? Thanks for any help! 73 de John, WB4GLJ ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
