[Lowfer] LOWFER receiver conundrum.

[Ben Hall]

Good evening all,

I've been using my Elecraft KX3 with a Jackson Harbor Press upconverter 
to monitor LOWFERs.

The combination of the KX3 plus the converter has some drift.  I'm not 
sure if it is the KX3 or the converter.

But...being that I like to build stuff...I figured I'd build an 
OCXO-driven AMRAD converter similar to those built by Todd Roberts, 
WD4NGG.  I even found a very similar 3 MHz OCXO on the e-place.  :)

So...the Todd Roberts design upconverter will eliminate the converter as 
a possible source of the drift.  But...now what do I do about the KX3?

So I started pondering a SoftRock SDR-type receiver with the clock 
source being either the 3 MHz OCXO above or my 10 MHz HP Z3801.  (GPS 
disciplined oscillator)

In both cases, using a simple prescaler or ripple counter frequency 
divider cannot cover all LOWER and other frequencies of interest.  (SAQ, 
135 to 138 kHz, 160 to 109 kHz, 472 to 510 kHz, etc.)

So here's the question...there are plenty of articles online using a 
reference oscillator and PLL to generate a *higher* frequency than the 
reference.  (IE:  the microwave folks generating multiple GHz 
frequencies from 10 MHz)  But...I've yet to find anything about using a 
PLL and reference oscillator to generate a frequency *lower* than the 
reference oscillator.

I know some folks here with transmitters have locked them to either an 
OCXO or GPS.  Can someone point me to an article on how this is done?

thanks much and 73,
ben