[HomeBrew] Panadaptors

[WB6BLV]

Many years ago I constructed a very simple Panadaptor,
so I could see about 500 KHz of each band I used.  It has
been so long since I used it that I have forgotten the purpose 
of the crystal in the last receiver stage of the adaptor.  Anyone
who might be able to help, I will gladly send you the schematic.

As I recall, the unit samples the output of the first mixer in the\
Rx, and heterodynes it with a local HFO that is swept in sync
with the sweep of the display CRT.  Then come a stage of
intermediate frequency amplification, then this crystal stage, then
a diode detector to drive the vertical plates of the CRT.  I wonder
if the crystal is used as a second mixer to rescale the sample to
original frequency, since the crystal matches the offset of the HFO
from the sample exactly.

Any assistance appreciated

John