[GreenKeys] GreenKeys Digest, Vol 96, Issue 7

[John Nagle]

> From: Paul Beckmann<wa0rse at gmail.com>
> Subject: [GreenKeys] Where to start?
> To:greenkeys at mailman.qth.net
>
> I now have a collection of RTTY machines that cover all functions. (Model
> 15, TT-14TD, and Kleinschmidt TT-272/FG). These pieces have not been run in
> a while. The Model 15 was running at one time before I inherited it as was
> the Model 14 TD. The 272 was running before being acquired by a party in MA
> and then shipped to me.
>
> Here's the question of the day for Greenkeys: Do I dare plug these things
> in and flip the power switch? Am I in danger of braking something? I've
> checked to see that no major pieces of debris, animal parts or waste, or
> broken pieces are lodged within. What should I watch/listen for? I assume
> it would be a good idea to, rather quickly, power the loop to prevent them
> from running "open". (I don't think that's the technical term, but you know
> what I mean.) I can try the Model 15 first, maybe with the Dovetron as a
> loop source, see if it prints what I type, and add the 272 to the loop.
> Does that make sense?
>
> My inclination is to dismantle, clean, and lube/reassemble everything
> first. However, it seems worthwhile to power them up to see if they work,
> what their issues are, and then make a decision on the sequence of TLC to
> give them.
>
> Any ideas and/or suggestions?

    I'd suggest the following for the models 14 and 15:

First, try turning the motor by hand.  Those motors
rotate counterclockwise viewed from the fan end.  It shouldn't
be that hard to turn the motor.   This is the "running open"
condition at slow speed.  If something is seriously jammed,
you'll find out at this stage.

Then manually press down the selector magnet plate (the
metal plate the selector magnet attracts) and continue
to turn the motor.  After one cycle, the clutch should
release and the motor should then turn without much
happening.  That indicates the clutch is basically
working.  Be gentle with parts in the selector magnet
area; that's the most fragile part of the machine.

Then push each typebar down and release it, to see if it
returns properly without sticking or jamming.  This
way you'll find out if you're missing springs, or if
the typebars are too dirty or un-oiled to move properly.

Try this simple electrical check.
First, measure the resistance across the printer
selector magnet input.  It should be around 55 ohms.
Then take a small 9V battery and apply it to the printer
magnet input.  The selector magnet should click.

If you get through those checks, it's probably safe to
power up the motor. The motor may have problems
of its own, so make sure you have a GFCI and a circuit
breaker in the power line. Check for cracked insulation
on the motor leads.  Ozone from the motor indicates trouble
with the centrifugal starting switch (this assumes
a synchronous motor).  Motors are compatible from 1924 to
1959, so motor replacement isn't hard.

It's quite likely that a dirty machine will have either
a clutch that won't drop out or typebars that won't return.
Here's the cleaning process.

http://www.aetherltd.com/refurbishing15.html

You don't have to dismantle much.

			John Nagle