[GreenKeys] Model 15 Electrical and Conceptual Help

[Thomas McCourt]

Hello greenkeys, my name is Thomas, and I am a chemical engineering junior
who has been interested in mechanical calculators and teletypes for a
number of years. I was just able to acquire a model 15 off facebook
marketplace about a month ago. From my experience with messing around
with typewriters and my Friden calculators I feel pretty confident that I
can figure out working with the mechanical side of the model 15, but I'm
entirely out of my depth on the electrical side of things. How electrical
stuff works on a fundamental level has been entirely non intuitive for me
and is the reason I didn't go for ECE, and I simply don't know what I don't
know. I don't want to fry components of this thing, so I'm here.

I've done some research and I've watched all of the Curious Marc videos
where he restores a 19 and a 15, and I've downloaded and started to read
the manuals he archived. I also tried looking through the archives of
greenkeys, but I didn't see any way of sorting it by topic. I still tried
looking through 1.5 years of the subjects, but I didn't see anything which
applied to my situation.

My 15 came wired up with a 4 prong plug where 3 of the prongs are
parallel and the other is perpendicular to the others. It also came with a
stand which had 2 2 prong wall outlets, the 4 prong, some large 2 prong
I've never seen, and ports for the send and receive. The stand itself had a
male 2 prong plug. The last time this was used seems to be in 1958 in a
hospital based on the paperwork that was under the stand.

With all of that said, I'll ask my questions. Can the 15 be wired such that
it can be plugged into a standard US outlet without the stand using a
normal plug? From looking at a wiring diagram which looks like it matches I
think it says that it can take 110V AC from the 4 prong plug, or 120V DC
from a different plug. Next, how do I set up a current loop so it can just
print to itself? What do I need to buy/build to be able to connect a
computer to it? With the photo I hopefully attached correctly, what are the
intended purposes of the ports under the stand? What are things I should be
especially careful of when working on this, in any sense?

Sorry for all of the questions and text, but I wasn't able to figure this
stuff out from my research thus far,
Thomas M


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