Re: Calibrating the Oscillator and Other Start-Up Questions for K3

Posted by Julian, G4ILO on Feb 21, 2010; 9:21pm
URL: http://elecraft.85.s1.nabble.com/Calibrating-the-Oscillator-and-Other-Start-Up-Questions-for-K3-tp4608623p4608762.html

I can't answer all of those. As for the frequency calibration there are many ways to do that, and it probably isn't all that important anyway unless you are doing some specialist operating that requires you to know your frequency to within a few Hz, as it is unlileky to be all that far out as received from the factory anyway.

Whether you use a broadcast station or a frequency standard like WWV really depends on which you receive strongest. If using a broadcast station then Deutsche Welle is generally regarded as being pretty accurate. If you tune through the SW band in SSB 1KHz off the 5KHz multiples you'll probably notice that most stations give an identical pitched heterodyne, a few don't. Don't use any of the latter.

I use WSPR (one of the modes developed by K1JT) which demands high frequency accuracy and one of the features of the latest WSPR software is a tool that measures an audio frequency, to aid with transceiver calibration. So I use that to measure the frequency of the heterodyne when 1KHz off, and adjust the oscillator calibration value until I get as close as possible to 1000Hz.