20 Dec
2022
20 Dec
'22
10:06 p.m.
Peter, thank you for the reply! i had to wait a bit for it to get dark
enough, but i just checked and i could not see any visible arcing inside
the chassis when the terminal is powered on. there is a slight buzzing
noise coming from the problem area but i suspect that is normal.
i did notice something new and potentially enlightening though, this time
when i turned the terminal on i could see several lines stretching
diagonally across the screen that were not there before. i also checked the
transformer(?) above the power distribution board while the unit was
powered on, it does not seem to be overheating.
On Tue, Dec 20, 2022 at 1:09 PM Peter Coghlan via cctalk <
cctalk(a)classiccmp.org> wrote:
I had something similar with a VT220. I didn't
get around to
investigating it
before the flyback transformer failed :-(
I can only suggest to run it for a short time with the cover off and the
lights
out while looking for any glows / discharges around the flyback
transformer,
the EHT cable, the EHT connector on the tube and the tube base connector.
Regards,
Peter Coghlan.
Ps: Anyone got a flyback transformer for a VT220?
i have a VT100 that is working fine (powers on, navigates setup,
saves/restores settings, etc) but has an unpleasant burning/ozone odor
coming from the rear of it. i suspect something is running hot but i am
not
sure what, i do not currently have an IR camera
in my hands- working on
that. the original power supply has failed and is currently in storage,
so
the terminal is being powered by an ATX power
supply and adapter board
for
the time being. this eliminates the usual R27 as
being the culprit.
as best i can tell, the smell is strongest just above the power
distribution board, around the neck of the CRT. appreciate any
suggestions
you might have!