[GreenKeys] Telex/TWX?

[George B. Hutchison]

TWX = Teletypewriter Exchange.  Telex used 5-level code with model 32 
machines at 50 baud, while TWX was eight-level at 110 baud, employing 
model 33s, and 35s if it was a heavily used circuit.

I believe that most of the telex  was done with high-voltage 
switching, as a telex line could really knock one on his ass. Latter 
day telex did use audio tone pairs as the high voltage switches also 
fell into obsolescence.

TWX was done with audio tone pairs, (originate and answer) and rode 
voice-grade dial-up circuits. TWX used a reserved area code (910), 
which was absorbed into the general switching arrangements as TWX 
became obsolete.

Perhaps one of the retired Western Union folk here on GreenKeys can 
supply better details.

George - W7TTY