[GreenKeys] Model 28 stock ticker progress

[Peter Gottlieb]

Update:

I have made some progress on several fronts with this machine.

Many thanks to John W9DDD I now have type boxes.  They are set up for 
weather symbols which is interesting.  The character ordering is 
completely different than the standard.

After running and oiling the machine seems to be working.

I made repairs to the plastic front where it attaches to the frame and 
those areas were cracked and missing.

I programmed an Arduino to send characters to the 28.  For now I just 
step through all 64 possible characters.  The speed of the unit is 
indeed 135 Baud and taking a video of the code bars shows them stepping 
through the binary possibilities.  So that is working and what I want to 
send gets to the code bars.  That's a good first step.

But the character encoding is very, very odd.  I'm not sure if I should 
rearrange the type box or not.

And I am confused about the printing in two rows.  The 573-140-100 
manual I have doesn't cover that.  But when I stepped through all 
characters the first half were on the bottom of the tape and the second 
half were on the top.  But not the same, they have different characters 
printing.  So there must be a shift code.

Once I understand this I can make a map and control what I print from a 
look up table but for now it's very confusing.

I tried going to Staples for a typewriter ribbon but all I could find is 
a little calculator ribbon but it was 1/2" and I could modify the spools 
so it's at least printing until I can find a proper ribbon.

I also need to locate some 1" paper tape.  For the moment I am cutting 
1" strips from regular paper.

Peter