[GreenKeys] FRXD Update

[jhaynes@alumni.uark.edu]

Yes, as noted the cabinets containing FRXDs were usually multiple units 
and were presumably scrapped when the systems they were used in were
scrapped.  I'm not aware of any cabinets being built by Teletype, tho it
is certainly possible.  Teletype did make cabinets for the 28-line
narrow reperforator transmitter stands.

You could make your own - I remember seeing some at an FAA site that
were pretty obviously homemade (or made in their own shops, or made
by a contractor for them)  They were made of plywood, sat on the floor,
had a shelf for the FRXD.  The FRXD compartment was lined with acoustical
ceiling tile.  (The old fashioned kind that was just perforated with a
whole bunch of round holes)  The front sloped and had a window in it.
There probably was a light because I don't remember it being dark
in there.  I don't remember what, if anything, was in the bottom of the
cabinet, nor whether the bottom part had doors.  Probably there was at
least a tape winder for the tape coming out of the reader.  There may or
may not have been anything like a scramble bin to hold the tape loop 
between punch and reader.

Something I have done with an FRXD is to mount it on one of the military
cabinets that were made to mount an XD and a reperforator.  There are
several of these, all of them excessively heavy, and known by names such
as AN/TGC-3, TT-10/FG, 132A2, 133A2.  They include a scramble bin to hold
the tape loop.  When I was using this in the past I just used a cardboard
box as a dust cover over the FRXD.  If I get around to reviving it I will
probably make a wooden box with a window in the door that just sits on the
table and encloses the FRXD.  

The AN/TGC-3 or 133A2 set contains a rectifier and a couple of repeaters
in the cabinet.  The TT-10/FG or 132A2 set looks the same externally;
but if you find one don't tear it up until I talk to you about it.
This set contains a one-tube electronic timer that is intended to supply
start and stop pulses to the receiver in sync with the distant transmitter
sending continuously from tape.  It is sort of a very primitive version
of K6STI's electronic flywheel in his RITTY software.  I sure wish I could
get my hands on one to test it and see how well the synchronizer works.