Hello all,

I just revived a 17" crt computer monitor with the only obvious fault
beeing the shorted line output transistor
(a 2SC5148 replaced with a BU4508AX). When powering on the monitor,
with the video cable disconnected
there is no apparent problem, a moving warning about disconnected cable
just wanders on the screen changing colors. If I connect the video
cable to a turned off computer, the monitor starts to whine for about a
second and then shuts down, when the computer is turned on, the monitor
turns on and works very well.
The "whine" appears for a second or so each time the computer goes in
energy saving mode and before the monitor finally shuts itself down.
Turning off the monitor with its button doesn't give any whining sound.
I suspect this whining problem it's what killed the original transistor
but I don't really know what to look for.
I haven't been able to figure out the brand of the monitor.
Any hint?
Thanks in advance

Francesco IS0FKQ