[Milsurplus] Astro Communications Laboratory, Model SDU 101, Signal Display Unit, S/N128

[antqradio at juno.com]

Picked up the above at the Radio Meet in Henderson, TN.  Seems to be two
panoramic displays in a 3.5 X 19 inch rack.  One input is marked, in
pencil, 21mc the other 30mc.  Both display modules look identical with
the same coil or IF type transformers, transistors etc.  There is a
provision for a display marker crystal oscillator but the crystals are
MIA.

My questions are:
What is the input frequency range or how broad does the internal VCO
sweep?
What are the crystal specs for the marker?
Does anyone have a manual I can copy?

Would like to mate this with some of the CEI or WJ receivers that I have
to cobble together a "system".  A Google search led to Technical Services
Laboratory, Inc in Florida.  Seem that they have acquired the assets of
ACL.
Any information greatly appreciated.
Regards,
Jim