3

I received this off eBay yesterday and the seller had showed images of it working. The CRT shows many signs of life, I hear static when it turns on, a sound when I switch resolutions, the degaussing sound when it turns on, the indicator LED stays when its receiving input, but it just stays black.

It has VGA and BNC connectors at the back but the problem is the same with both. I twice now have booted the PC and a faint image of the BIOS screen very quickly expands on the screen and fades out unil its black again. Ive also seen the OSD do the same thing once (I think also during boot).

I'm just not sure what's going wrong. At first I thought it was a resolution issue on my PC's side, since both the seller and an online source listed it as 1800x1440x76hz (I assume the seller got their info from there), but the manual says its max resolution is 1600x1200x85. Ive tried pugging it into my motherboard's VGA port, an old discrete GPU's VGA, a DisplayPort to VGA adapter and an active (tested and working) DVI-D to VGA adapter adn the VGA port built into an older laptop. All of it behaved the same.

Windows 10 correctly identifies and name of the monitor, and I can change the resolution and refresh rate, but the screen reamins black.

I would really appreciate some help. Thank you!

5
  • 2
    For other readers, and because the original post does not mention it, this is a cross-post/duplicate from Super User SE.
    – Justme
    Apr 20 at 13:33
  • The original post has been deleted in favour of this version. I'm still looking for answers here, since the original didn't get anything addressing the question
    – Idmi
    Apr 20 at 14:57
  • I owned one of these monitors (with a second VGA input instead of BNC connectors) until a few years ago. The brightness of the display had faded somewhat over time, to the extent that I used it with its brightness settings at max. With settings turned down, the the desktop image could be completely black, with only the menu/OSD showing. You may find that it's a physical component failure (e.g. flyback circuitry) that requires repair in a similar manner to an old CRT TV. Beware high voltages inside!
    – Kaz
    Apr 21 at 17:44
  • Does it flash the BIOS logo every time you reboot? Or just the first time? Apr 22 at 14:51
  • It happened twice but I haven't been able to repeat it since. however, my PC doesnt always output the BIOS screen to the same display. I also cant remember how I had it connected to my PC (i.e. which output from the CRT or which port I conencted it to), so I may just not be repeating the same conditions.
    – Idmi
    Apr 24 at 11:47
8

In the following I'm assuming you don't have the manual brightness control turned down to the minimum. That is the only trivial problem that might cause the issue.

When the CRT isn't even able to display it's own OSD, there must be something seriously wrong with it. The OSD is produced by the CRT itself and should come up even without a working connection to an image source.

The digital part of the monitor is certainly OK when Windows 10 is able to identify it properly.

That means the analog part must have a problem. Old CRT monitors really are susceptible to damage from transport shock. It consists of some quite heavy parts like the flyback transformer or big capacitors soldered to the PCB that have a tendency of breaking loose by their sheer mass when handled in transport.

And, no offense intended: If you need to ask what could be broken, you probably shouldn't try to open the case. CRT monitors work with very high hazardous voltages, that can kill you and can be present even long after the device has been switched off.

Get an expert to repair the monitor (to me, it sounds like a simple fault, as it sounds as if the flyback transformer and the tube itself are OK), or write it off as transport damage.

5
  • Yeah, I have some experience repairing graphics card but this is way out of my comfort zone. After doing some research into CRTs it sounds like it might be the flyback transformer, since I havent been able to repeat the image flashes. My guess is that without that flyback working properly, static built up in the display and it can't show anything now. But I'm just googling stuff. What makes you say the flyback is OK?
    – Idmi
    Apr 21 at 9:21
  • 3
    OK, because you have a picture at all (even if only momentary). With a broken FBT, you wouldn't see any picture. I'd rather assume something with the power supply is broken. With the CRT in transport recently, it's relatively likely some of the solder joints holding the heavy FBT on the PCB are loose.
    – tofro
    Apr 21 at 11:19
  • What is the OSD? Is it an image generated within the monitor itself in response to a Power on event? Apr 22 at 14:54
  • @WalterMitty The On-Screen-Display displayed when you press one of the settings buttons.
    – tofro
    Apr 22 at 16:00
  • Thanks. And yes, that's a good test of the screen. Apr 22 at 17:02

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.