[GreenKeys] RTTY VS wire loops, Robot 800C

[Tom Hunter]

It seems some people are confusing RTTY with the old fashioned wire loops
from when teletypes began replacing telegraph keys and sounders from city
to city.

That is when FIGS-H motor controls and Blank-Blank keyboard lockouts on
model 15's were useful.

Obviously they are of no use on RTTY.

By the way, I just acquired a ROBOT 800C RTTY keyboard. In XMIT mode it
will type directly to the TTY loop! The speed can be changed with a few
keystrokes and it can generate a line of RY's or a FOX. I can see using it
to test a lot of Teletypes. It requires an external loop supply. I had
already built a 60 Volt, 60 mA  loop supply to avoid stressing the keying
transistor too much. It drives my skintight 28 perfectly. It will also
demodulate 170 Hz shift. I have used it on ITTY news. I have been recording
things of my own on a $20 phone that I use as an MP3 player. 11025 and 8K
bits per second (as ITTY uses) is fine and it beats the heck out of a
cassette recorder.

The Robot needs to be used with a video monitor. I run it in to the analog
input of an old LCD TV.

I also use that 60 Volt loop supply with my MFJ-1224 TU.

Tom   N3CRK
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