The Model 33's I bought back when I was a teenager, were all ex-Telex use and 
had exceedingly complicated wiring harnesses as well as built-in modems. They 
had paper tape readers and punches with various auto-start/auto-stop relay 
options.


The exceedingly complex wiring harnesses were to add various options. The 
wiring harnesses made the wiring of the unit look, literally, a thousand times 
more complex than it actually was.


In the end all I ever did was find the magnet wire, and the keyboard contact 
wire, for the main unit and the punch.


I usually also found a useful current loop supply in the base. Sometimes I 
would find bipolar relays and 20mA/60mA conversion supplies. I was a little 
surprised at some of the current loop supplies - some of them weighed 20 pounds 
and were obviously made for driving exceedingly long lines (open-circuit 
voltage way over 100VDC). Seemed odd these were in there considering the units 
had modems just a foot away from magnet and keyboard switch.


Tim N3QE

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