[GreenKeys] Newbie setting up an m26

[Jomar Quilatan]

Greetings!

New list subscriber here - and a starting teletype user also. I got my
hands on an M26 not long ago in the hopes of getting it to work. Though the
keyboard area exhibited typical storage dust, the interior looked
surprisingly clean for something likely to have sat for 50+ years unused.

Anyways - I’ve read up that a loop current would be necessary to govern the
selector magnet and stop the “chattering” that the machine does when the
wires aren’t connected. Also possibly the way I test if the message
encoding/decoding works. Aside from the power cable, this has another with
two wires coming out of it, which I suppose are hooked up to the loop.

 I understand these also had a special table made for the unit to house the
paper roll and some kind of circuit - which this unit sadly did not come
with. A couple of questions as a result:

1) Assuming a 60mA basis, would this need to be a high voltage (120V)
solution or can a lower value work just fine? I’ve heard the that the
magnet resistance is no more than 120 ohms, but I’ve seen some people
supply a 120V 60mA source likely to the loop. Just assessing the power
supply and other equipment I need to get that might exceed the ratings of
the components of my Arduino kit.

2) On top of that, any newbie-oriented suggestions for testing out /
running diagnostics on the 26? I don’t mind wiring but have limited bench
tools and no solder (yet).

Regards,

Jomar Quilatan
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