Jess, One of the likely problems may be a solder bridge on the thermistor board itself. First check to see that the voltage at U6 pin 5 is 4 volts - if it is substantially different than 4 volts, you for sure have a poblem on the thermistor board.
The PLL temperature compensation keeps the PLL reference oscillator frequency constant with changes in ambient temperature (ambient is inside the K2 enclosure). A component failure is way down on the list of suspect 'things that could be wrong', but it is admittedly a possibility. First check soldering and all component values again. When you are finished, check soldering, then recheck soldering and when you are finished with that, check the soldering - that is the most common cause of problems. 73, Don W3FPR > -----Original Message----- > > I am at the point where I am testing the PLL reference > oscillator. To the > best of my ability, I have verified the components, values, assembly and > solder connections. > > When I put the K2 in freq counter mode, the PLL freq is not > correct. Pushing > the band + displays about 1620-1640 and jumpy. On band -, it > displays around > 1030-1050 and jumpy. Rotating the tuning knob displays about the same > symptoms. I am thinking that either the varacter or crystal may be bad. I > know that it is not the cal fctr function or probe as the rest of the freq > displays are stable and the correct values. > > Any help or tips would be appreciated. I am going to call > Elecraft tomorrow, > but thought that there may be some of the great help here that > there always > is. > > As another question, what problems is the new thermistor mod > really correct > and do you think that this may or may not be contributing to the problems? > Again, all of the values are correct and construction appears to > be correct. > > Jess AE0CW <>< > > -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.338 / Virus Database: 267.10.9/72 - Release Date: 8/14/2005 _______________________________________________ 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
