[Elecraft] PLL ref Osclllator range test

[James T. "Jim" Rogers]

Ken wrote:

Am putting my K2 together, and have a question on the Alignment test, Part
II,
PLL Reference Oscillator range test. What I am getting is a high of
12,100.37,  low of 12,081.51
thats about 18.56 Khz, about 3 Khz high by the manual, any suggetions ??

Let me try this again without fouling it up by dropping words....

Ken, I just spent some time this afternoon trouble shooting that circuit for
another K2 builder. If the VFO linearization worked and if you measure the
control voltage out of DAC U5, I believe, and it is in specification, I
would say your crystal is just a bit more "rubbery" than some. Trying to get
crystals from different manufacturing lots to behave the same is not easy.
Check the control voltage out of the DAC on pin 7, that will be a true
reference because it is programmed by the MCU.

Ain't this fun!!!???

73,
Jim W4ATK
K2 #4028