24 Jan
2006
24 Jan
'06
3:56 p.m.
jim stephens wrote:
how freely does the mechanism move on the carriage?
sometimes this causes
jitter, though not at rest.
Freely enough, with the power off obviously. There is a little
resistance as the ribbon feeds, but not much.
look at the power to the control circuit and the
drivers to the servo
motor and
make sure it's not about to blow, and maybe has high ripple on it if the
jitter
is happening at rest.
It does happen occasionally. I haven't scoped the PSU rails yet but on
the odd occasion that it does jitter at rest, it doesn't sound ripply.
What I have found is that it seems to do it when the opto-interruptor is
at certain positions. Sometimes it will print 1/4 of a line, skip a
1/4, print another 1/4 and skip the rest.
I took the opto sensor assembly off and blew it out with an air duster.
This didn't help.
Gordon.