[GreenKeys] a couple M28 / TT-176C questions

[Chris Elmquist]

Hi Guys...

I've been plinking away at restoration of an M28 "Skintight", TT-176C for
a while and am just about ready to call it done.

However, I seem to have had a small setback in print quality since putting
the lid on (not likely related) and giving it a more serious workout.

The print is quite light on the left side of the platen.  Additionally,
when $ (dollar sign) is printed, it is extremely light and then it also
prints " (double quote) on top of the $ and the double-quote is actually
pretty crisp.

As the carriage moves more to the center, the print quality improves,
the " stops printing on top of the $ and finally, when we get to the
far right, $ looks pretty good too.

Other characters print pretty well across the entire width, just a little
lighter on the left.  No other characters do the double hit thing that
$ and " are doing at present.

I have confirmed that the $ and " are not stuck together since they are
adjacent in the type box so something more sinister is likely at play.

I'm looking for some guidance on where I should look in the manual for
this type of problem and adjustment.  Obviously, there could be multiple
maladjustments at work here.  I am prepared for that :-)

Also, on the TT-176C, there is a red lens with light bulb behind it on
the front panel.  What is that indicator for?  I assume there is some
code, that when received, will light the light but I'm not finding any
clues as to what the code is or if that is actually how the light works.

One guess I had is that it would turn on when BELL was received but
that does not happen presently.  New bulbs are installed in all sockets.
The two lamps that light up the print area work nicely and look very nice.

Finally, there is an unlabeled key on the keyboard bottom row, just to
the right of LINE FEED which puzzles me.  It appears that pressing it
once does nothing but pressing it twice causes the keyboard to lock.
To release the keyboard, I have to press the red KBD ULNK at which point
I can send again.  I do see that each press of this unlabeled key does
cause traffic on the loop but if I just press it once and then press a
different key next, the keyboard does not lock.

I have only this M28 on my loop along with loop supply.  No other gear.
So, keyboard is looped to printer.

Thanks for any input you can offer on these topics!

73, Chris N0JCF
-- 
Chris Elmquist