Trouble shooting with a CRT Monitor

[vivek16]

I recently did a new computer build (very nice stuff, works great) and was attempting to put the old rig back together in the basement. However, the CRT monitor will not turn on. I just have it plugged into an outlet (no video feed) and when I push the power button, no lights turn on. I can, however, hear a faint clicking noise near where the power cord enters the monitor.

Any ideas? I don't want to take it apart and I think it's probably busted.

-vivek

[DonRotolo]

It can most certainly be repaired, but before you remove ANY of the screws, think: Do you have any training on dealing with high voltage? Or someone nearby (old ham radio operator, or TV repair guy) who can stop by and explain how to avoid killing yourself?

If not, stop. Recycle it.

I was zapped by CRT voltage once, and lived to tell - not many can say that. And, that's not the most dangerous thing in there.

It is probably a fuse in the power supply, but I really hesitate to encourage you to go in there. It's not like a computer, where nothing's lethal - in a CRT device, almost everything is dangerous, even the plain metal chassis.

Don

[Al Skierkiewicz]

Vivek,
If it has no video feed and is a "green" monitor, it may not turn on until connected to a computer. Many monitors are looking for the presence of video sync before they will fire the power supply. Let us know what symptoms you have when connected to the computer.

[vivek16]

This has been a family computer monitor for about 8 years now. It always atleast lights up the LED in the front. It is now not even doing that. Again, I am also hesitant to open it. There is a clicking noise back where the PSU should be but besides that, nothing whatsoever. I've tried hooking it up to 2 different computers. Still nothing.

[Al Skierkiewicz]

The clicking noise could be one of two things and it would (should) have clicked in the past, you just didn't notice. If the LED is not coming on that sounds like the low voltage power supply but the clicking is also controlled by the very same power supply in most cases. I would suspect at this time that the low voltage power supply is likely lost a capacitor and is putting out largely AC voltage. This would prevent the startup circuitry from turning on the rest of the power supplies and thus firing the monitor. However, since it is eight years old, it is time for a change. Unless it has remained off for weeks at a time, the CRT is likely less than optimum and the other caps in the monitor are likely in poor condition as well.
There is another possibility but it leads to the same conclusion. A dead short on/in the supply could produce the same symptoms. Still better to replace with an nice LCD.

[Qbranch]

Originally Posted by Don Rotolo

I was zapped by CRT voltage once, and lived to tell - not many can say that. And, that's not the most dangerous thing in there.

*chuckle* The flyback transformer usually does have the last laugh.

-q

[vivek16]

I did a new computer build and the new family computer now has decent stuff and a nice lcd monitor. I was just trying to boot up the old one to play around with it. If it doesn't work, then no harm done.

[Al Skierkiewicz]

vivek,
Keep an eye out for a monitor that is getting tossed. It would be a perfect addition to this setup.
I had a friend who asked me to help out a startup business a few years back. The business was going to take in used monitors and fix them and tweak them up for resale. The first part of the business was going fine. People wanted a place they could send their old monitors and not have to worry about disposal. I was involved to resurrect dead devices and there were a lot. I tried to tell them that this was not a great business idea but they continued on. They also payed on time which was an incentive for me. There is nothing more demoralizing then getting something fixed only to find out it was not worth fixing to begin with. The business closed after only two months.