[Elecraft] Adjusting the 4MHZ Master osc in the K2

[Ron Willcocks]

Hi,
     I know this is an "Oldie" on the Reflector, but possibly worth 
bringing up again for the builders that have arrived since it was last aired.
A while ago, I built K2# 5577 and it was my "second set" until I sold off 
my old K2 #2204 to a keen chap here. It didn't take me long to realize I 
had made a less than perfect job of setting the 4 MHZ Master Oscillator 
when I joined in a net and found my readout didn't match the net frequency.
In the past, amongst other methods I had used to set the 4MHZ oscillator, 
was the one put out by Wayne N6KR, and I hadn't had much success with it, 
but decided that if anyone should know how to set the oscillator it should 
be the designer, so I gave it another try.
Without going into great detail, the method involves adjusting C22 (after 
tuning in a SSB signal "perfectly"), until the frequency readings at TP1 
and TP2 are the same.
My first problem was tuning a SSB signal in "perfectly", but it was fairly 
easily got around by listening to WWV and altering the dial on the K2 until 
there was no difference in the audio while switching between USB and LSB.
Switching to CW mode and using "SPOT" seemed to confirm I had the setting 
right.
 From there I followed Wayne's instructions and soon found where I had been 
going wrong in the past....I hadn't been following steps 6 & 7 in the 
instructions, and that made all the difference. I was able to get the 
frequency around 20hz off, which is far better than the 220hz discrepancy I 
started with.
Where are the instructions to use Wayne's method??... On the Elecraft site 
go to "Builder's Resources" and then select " Frequency Calibrating the 
K2's 4Mhz Master Oscillator".
Appologies to all those who find this "old hat", but I am sure there will 
be a few look-ups amongst the newer Elecraft fraternity...
73.......Ron ZL1TW


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