On Sun, 16 Mar 2003, Tony Duell wrote:
So if the return character is not getting to the rails
correctly then
firstly it won't punch properly and secondly, it won't be detected by the
approipriate lever in the function unit.
I haven't be able to verify what character is being produced because the
durn carriage is stuck on the right. Once I get the carriage returned
then I can determine what's going on.
So let's get that missing bit back first. Are you
running the machine in
LOCAL mode (i.e. from its own keyboard to the printer?). If so, the
Yes, LOCAL mode.
problem could be in the transmitter side (contacts on
the keyboard, for
example). Or it could be a problem in the RX unit (sticking lever). I
think it's safe to assume that the solenoid driver is not the problem
here (it's not going to mangle only one bit).
While I can't say I examined it to the point of ruling this out, I didn't
notice anything wrong with the levers. However, it is an obvious place to
start.
Incidentally, the carriage is fed by the 'spacing
mechanism' which drives
the left hand sprocket for the toothed belt. At the bottom of this
sprocket shaft, right against the casing, is the spacing ratchet with the
pawls to move it on one character, and to allow it to be released for a
carriage return. IIRC, _carefully_ frobbing levers in this area will
release the pawls and allow the carriage to return.
I'll look into that. This is my primary concern as of now.
Whoever
designed the ASR33 must have sold their soul to the devil to make
it all work. It's amazing how intricate and delicate everything is, and
how damn kludgy as well.
I find them rather beautiful...
I agree, but I still can't believe this thing works and stays together as
it does considering how delicate all the parts are and how delicately
everything hangs in balance.
--
Sellam Ismail Vintage Computer Festival
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