30 Jan
2002
30 Jan
'02
10:10 a.m.
On Wed, 30 Jan 2002, Tony Duell wrote:
This seems to match up with the behavior the terminal exhibited. I heard a
few 'plink' type sounds a few times, accompanied by 1/2 sec or shorter HV
drops. I'm guessing the flyback was starting to arc internally? This
terminal had done this off and on for a considerable amount of time...at
least a year. The flyback's case didn't crack on this one (that I noticed
anyway). I pulled it out of service the second it quit working, so that
could have something to do with it. I opened it up, and found a
considerable amount of smoke had escaped from underneath the flyback,
which would have explained the cloud and smell that prompted me to yank
the cord from the wall.
I can vouch
for that. My VT340's flyback let out its magic smoke about 6-8
months ago. Does anyone happen to have the service manual and or a
replacement flyback for this thing? I'd like to repair it in the near
future. What most often causes the flyback to go out? It worked fine one
day, the next it let out a cloud of smoke.
My experience with the VT330 and VT340 suggests that there's no other
component that fails to kill the flyback. It's just that the HV
winding in the flyback breaks down. The flyback case cracks, lots of
smoke comes out... You should check the horizontal output transistor (on
a heatsink near
the flyback) and all the diodes and capacitors round the flyback. But
most likely they're fine.
Will do. Do you have any suggestions on a replacement flyback here in the
US? I'd also like to find a service manual for this terminal, so that I
can go through the basic checks and alignment procedures once I find a
replacement.
-Toth