[Elecraft] K3(s) main oscillator calibration

[Wes]

The various reference calibration methods, including direct measurement of the 
TCXO that I do, just determine what the actual reference frequency is, but don't 
change it.

This value is then used internally to compute the correct frequencies.

Wes  N7WS

On 6/6/2020 11:47 AM, hdv at kpnplanet.nl wrote:
> Hi all,
>
>   
>
> In the CONFIG menu REF CALL the value of the main oscillator can be set.
>
> However, this does not impact the TCXO frequency at all in a direct sense.
>
>   
>
> Whatever the REF CALL value, the TXCO frequency stays the same.
>
> This can also be seen in the schematic.
>
> The TXCO just outputs 49.380 MHz and has no voltage/frequency-adjustment
> input.
>
>   
>
> So where and how does the frequency correction take place?
>
> Somewhere at the 15 kHz level or in the KSYN3 DDS / KSYN3A divider?
>
>   
>
> Who can explain the principle.
>
>   
>
> 73 Henk
>
> PA0C
>
>
>