ASR-33, was Re: DEC VT05 with OS/8 -- basic system rebuild?
ard at p850ug1.demon.co.uk
Wed May 13 13:24:11 CDT 2009
> It has an annoying issue with carriage return...If a CR is
> received, and if the print mechanism hasn't moved far enough to the
> right for the return action to build up enough momentum, friction
> causes the carriage to stop before it gets far enough to the left, so
> it doesn't trip the "the carriage has returned" lever. I don't know
> if it's a lubrication issue or if the CR spring is worn out. I'm
> pretty sure it's not the dash pot, as it doesn't get quite that far.
My first thought was the dashpot adjustment, but you say 'it doesn't get
that far'. I assume by this you mean you've stepped the carriage over far
enough for the piston to be entirely out of the dashpot cylinder, and
when it gets a CR, the carriage returns, but not far enough for the
piston to enter the cylinder.
To me this sounds like gummy lubricants. I wouldn't run a second-hand
ASR33 (or any other piece of mechanical equipment, actually) without
going over all the lubrication points. Actually, I'd strip it down, clean
off the old oil and grease and put it back together again (this doesn't
take that long if you have the manuals -- I did my first one while still
at school (so I was working evenings and weekends), I didn't have the
manuals, and I was learning as I went, and it only took a couple of
IIRC when it gets a crriage return, it lifts the pawls from the carriage
feed ratchet wheel at the front left side of the typing unit. At this
point the carriage is free to return (pullled by the spring), the pawls
only re-engage when it gets the next character. You should check this is
the case (if the pawls are not held off the ratchet wheel, then obviously
the carriage will be stopped). In the state where thhe pawls are lifted,
the carriage should move freely, you can move it by hand to see if it
seems to be sticking.
More information about the cctalk