Caveat : CRT Monitors contain lethal voltages, even when disconnected from power, do not attempt to open or repair any CRT.
So more than a few years ago I ”rescued” a couple of HP D2827A monitors. One was prefect, the other one would turn on and the front panel and lights worked but the CRT had no display at all and did not exhibit the high voltage thump and crackle as it powers up. Try as I might, I could not find a repair manual for the Monitor.
I've been putting the repair of all of my monitors for years. Finally after years of repairing my computers and their power supplies and reading untold many blogs, repair guides and videos I felt I was ready. Also I bought a proper discharge tool. The thought of using a home made tool was totally unpalatable.
Opening it up and looking at the motherboard marking it turned out the monitor was a re-badged Daewoo CMC518X monitor and the service manual was readily available.
It was fairly easy to find the culprit Q104, a transistor KTA1273-Y. This was mainly due to the huge burn mark and the exploded solder from the center pin. Unfortunately that part is no longer available, luckily a drop in replacement is still available KSA928A-Y.
I took the original part out and cleaned it up a well as I could before putting in the replacement. There was tiny balls of solder all over the bottom of the board which I painstakingly removed.
There are a couple of things that are a little out still. There is slight bow in the picture that’s not adjustable. The brightness and contrast are set up to max. However the monitor is now usable (shown connected to my MiSTer). Further troubleshooting will need to wait until after I've completed the other unfinished pre-COVID-19 projects littering my workroom.
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