20 Jun
2014
20 Jun
'14
2:23 p.m.
[TRS-80 M2 and printer]
I didn't get a cable for either the printer or the
external disks,
I seem to remember that early versions of the disk controlelr PCB i nthe
M2 has the internal and sxternal drives o nthe same bus. This had the
undesirable feature that if there was nothign conencted to the external
drive conenctor (no expansion drive unit or terminator), there was no
termination (and thus no pull-ups) on the intenral drive signals either.
The general result was a corrupted disk. Sounds like you hve the later PCB.
The priner cable is straight through from an IDC socket to a microribbon
plug. If you want one it's easy to make.
I'm having a heck of a time hunting down a manual
for the printer
though. I *think* it's a Centronics 703, but the 703 was blacked out on
the nameplate on the back, and there's no identification on the front. I
Ah... It probably is a Centroics 703. Is it the right colour ir is it
'battleship grey' like the computer? IIRC the rist Radio Shack 'Line
Printer' (which was not a ture line pritner, of course) was actually a
Centroics 703 with grey case mouldigns. No internal changes at all.
If this is the printer I am thinking of (and from your description of the
ribbon I think it is), the carriage motor is an AC shaded pole thign that
runs all the time. It drives a belt acorss the printer. Solenoids in the
carriage grab the top or bottom run fo the belt to move the carriage. Odd..
Anyway, I managed to get the service manual for the Radio Shack Line
Printer (the user manual mayeb there too, but I didn't need it) from
http://www.archive.org/ It might be worth a look.
definitely need to get a new ribbon for it, but it
looks like instead of
replacing the ribbon as a cartridge, you pull the whole ribbon out of
the screwed in case and then have to pack a new one in. The pinch
Yep :-(
-tony