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Purchased an Osborne MPV1024 monitor and it just works (lemmy.world)

submitted 1 day ago by [email protected] to c/[email protected]

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Last week I made a post asking if I should buy an old vintage monitor.

Well, I went back to the recycled goods store this week and it was still there, so $30 later I have it, and it seems to just work*

There's very little about this monitor on the internet, so I'm thinking of documenting as much as I can about it, especially as it's Osborne branded so there could be some interesting history behind it.

* The power button is stuck on, and it does an occasional unsettling arc sound and the image slightly distorts for a millisecond. I believe the latter is fairly common among old CRTs but I don't know much more than that.

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[–] [email protected] 20 points 1 day ago (2 children)

Do you know much about crt maintenance? If so get on it!

If not: it seems like it’s in good shape but based on your description of the arcing sound and image distortion you may have high voltage leakage.

Before investigating the fix for that start with basics: clean the inside of the case. Open it up, don’t touch anything dangerous yet (turn it off and disconnect power though, obviously). Blast out everything with compressed air. Dust build up, insect nests, etc can wreak havoc but I don’t think this is the issue. I bet it’s the anode cap

Pretty easy fix: clean the anode cap. Power it down, let it sit for a bit, look up how to discharge the tube (you basically bridge the anode to ground with something like a screwdriver. This is dangerous though bc very high voltage so watch a video to see what to actually do and use an insulated screwdriver, obviously)

Once the anode cap is off clean it and the area around it with isopropyl. If the anode cap is damaged that poses a bigger challenge, you can sometimes source a replacement still or bodge repair them if not

If it’s not the anode cap next check is flyback. This is easy to diagnose generally. Just look at it: does it have cracks, does it smell, burn marks, can you wiggle it/is it loose (power disconnected obviously) then that’s probably got some issues. Sourcing a replacement can be a pain

Finally check grounding straps. Less likely but could be a factor

If none of that works it’s probably arcing inside the tube. Sorry if that’s the case and enjoy it while it lasts, nothing lasts forever. This is probably not the case, maybe

[–] [email protected] 3 points 17 hours ago

The click and distortion is the auto degaussing. Probably happens because the power button is stuck down. You used to push and hold on some models to degauss.

[–] [email protected] 16 points 1 day ago* (last edited 1 day ago) (1 children)

This is dangerous though bc very high voltage

This cannot be stressed enough. You can kill yourself poking around in an old monitor. It's not even hard to do. There are thousands of volts in there, just waiting, even when it's unplugged.

All of this advice is not really wrong, but I would revise all of it to "leave the cover on, unless it's giving you an issue, in which case take it to someone who knows enough about this stuff to mess around with it safely."

[–] [email protected] 12 points 1 day ago (2 children)

Can’t learn if you don’t try!

But seriously that person is correct you can die

But also at the same time it’s a little overblown. My friends and I learned how to do this shit as dumbass 12-16 year olds without the support of the internet and we’re all still here. Research what you are doing, take your time, learn to discharge things safely. It’s not rocket science to discharge a capacitor or a tube. And with proper maintenance that monitor will run for at least another decade or two (but without it convergence issues and that arcing issue might worsen and take it out sooner rather than later)

If you really don’t trust yourself to do it then find someone else though. There’s plenty of dorks out there who love tinkering with CRTs

[–] [email protected] 2 points 18 hours ago* (last edited 18 hours ago)

https://www.ifixit.com/Answers/View/197/How+dangerous+is+it+to+work+on+a+CRT+display

Servicing a CRT-based Macintosh should be left to the professionals due to the inherent dangers. I avoid them as much as possible, even though I am thoroughly trained, with decades of experience working on CRT-based computers, monitors, and test equipment.

[–] [email protected] 4 points 1 day ago* (last edited 1 day ago) (1 children)

Thank you both for the advice, this was exactly what I needed - I know absolutely nothing about CRT maintenance but I have tinkered inside plenty other electronics before.

Before I do anything on it I'll be doing all the research I can to ensure it's as safe as possible and avoiding areas that can't be discharged, and otherwise hunting within my friend circles for a CRT guy who can help me with it.

Edit: this will all serve as a lesson for me taking on a more ambitious project I have, an iMac G3 that doesn't post. Unsure at this stage if the CRT works or not in it, but I believe something is wrong with the PC's PSU currently

[–] [email protected] 5 points 1 day ago

Just keep in mind that pulling the anode cap of a crt is genuinely lethal electricity. Like you can get zapped pretty bad by a power supply cap (you should get in the habit of discharging these too) but generally unless they’re seriously big caps you won’t die. A crt can kill your tho so make sure you discharge it correctly. That’s why I say watch a video on how to do it, there are plenty of them and it’s much better to see what to do than follow a text description. Keep in mind that sometimes you have to discharge 2-3x (not usually but sometimes, and never hurts to be safe). You’ll see a spark and hear a pop. You can get a tool to discharge but an insulated screwdriver is all I ever used

Macs of that era are a pain. Good luck. Check capacitors of course, replace battery, reset pmu. That era of mac you can get a service manual which is nice, get a meter and you can trace reference voltages thru power supply and logic board. Flyback is notorious in those imacs so look at that (same as above, check for burn, crack, loose, smell). 68kmla.org has a lot of great repair info on that era

[–] [email protected] 14 points 1 day ago (1 children)

Bruh this would have been the most bad-ass website on the internet in 1998.

The closest thing we had at the time was Craigslist missed connection.

We made do.

[–] [email protected] 2 points 1 day ago

We had IRC and AIM but it just wasn’t the same.

We searched yahoo and lycos. We asked Jeeves. We had it all.

[–] [email protected] 10 points 1 day ago (2 children)

Until I get a nice computer to pair with it (that is, not my Linux server), this just felt right to do with it

[–] [email protected] 4 points 1 day ago

my win11 (a necessity, not a choice) box at the office drives a 17in trinitron crt running at 1600x1200

[–] [email protected] 2 points 1 day ago

Needs to be 3.11 skifree

[–] [email protected] 5 points 1 day ago* (last edited 1 day ago) (1 children)

It's just SVGA; why wouldn't it "just work?" It doesn't appear to be weird or special in any particular way.

(Edit: other than being 240V/50Hz, which isn't normal where I am but presumably is normal in OP's country.)

[–] [email protected] 5 points 1 day ago

Welllllllll.... A couple points to mention are that it is SVGA but interlaced, so I'm doing a bit of messing with xrandr to get that working but otherwise it is happy doing 800x600 progressive

I also meant that I didn't need to do any work to it - it has a couple minor issues as mentioned but didn't have any major components that have failed (like the flyback for instance)

Also yes I'm based in Australia so 240v is standard here

[–] [email protected] 7 points 1 day ago* (last edited 1 day ago) (1 children)

My grandpa had a monitor like this - it came with a Osborne computer he bought in the mid 1990s. It was either a 486 or Pentium 1 (can't remember) and came with an Osborne-customized version of Windows 3.1 along with some floppy disks and CDs with Osborne software on them.

He was still using that same computer, with the same OS, until he moved into a retirement home in the late 2010s. He only really used it for writing stuff in some old version of Word, and playing Italian card games (Scopa, Briscola, etc).

I'm not sure what happened to the computer since it was all gone the last time I visited his house after he passed away. I live in the USA but he was in Australia so it was hard for me to try and keep on top of things like that.

[–] [email protected] 2 points 1 day ago (1 children)

I imagine a lot of these went that way unfortunately, including this one. They were difficult to use on Windows 95 onwards as far as I've found due to the SVGA resolution being interlaced, making them more tempting to toss once the Osborne PC became obsolete.

It's quite amazing he continued using it up to the 2010s, but I suppose when you have a completely offline system that already meets your needs, then it can't really go obsolete.

[–] [email protected] 3 points 18 hours ago

It's quite amazing he continued using it up to the 2010s

Yeah I'm surprised it lasted that long. He never used the internet or mobile phones and the Windows 3.1 PC was probably the only piece of modern-ish technology he used.

[–] [email protected] 5 points 1 day ago

Bro you have to have the screenshot be showing the post showing the screenshot. Do you even internet?

[–] [email protected] 2 points 1 day ago (1 children)

Butwhy.gif

[–] [email protected] 3 points 1 day ago

The ultimate plan is to have a full retro setup, and I will piece it together as I come across more components that I think will fit.

The dream would be a PC from about 2000, running Win2k but dual booted with something old like Win3.11 and/or DOS, and period accurate (but still comfortable) peripherals, so keyboard, mouse, and speakers.

[–] [email protected] 4 points 1 day ago* (last edited 1 day ago) (1 children)

The power button is stuck on, and it does an occasional unsettling arc sound and the image slightly distorts for a millisecond. I believe the latter is fairly common among old CRTs but I don't know much more than that.

Sounds like a degauss!

It's relatively common for CRT screens degauss as they turn on, so it makes some sense that it's still happening, even if the power button otherwise doesn't work - the degauss must be triggered by a different internal mechanism than the one controlling the power

[–] [email protected] 3 points 1 day ago (1 children)

This monitor has no OSD or button to trigger a degauss. The coil will be wired directly to AC via a posistor, so it's entirely passive and will only trigger again when the monitor cools down.

The distortion is caused by the high voltage arcing over, which droops and interrupts beam deflection for a moment. I wouldn't want to run it this way for very long, because it can damage the flyback transformer over time (although the flyback could itself be arcing anyway).

[–] [email protected] 2 points 1 day ago (1 children)

Thanks for the heads up - it'll stay as a very occasional use monitor until I either feel comfortable enough to look inside (after lots of research, given the voltages within) or find a friend experienced in CRTs. I really wouldn't want to blow it up when it could've been prevented easily by maintaining it.

[–] [email protected] 3 points 22 hours ago* (last edited 20 hours ago)

Ragebutt's advice is good RE: maintenance. I would take the back off, make sure it's discharged then clean around the anode cap and in general make sure there is not excessive dust/soot that could form a path for electrical discharge. Clean the anode with alcohol, apply a little dialectric grease to the cup and put everything back together. There is a decent chance that will help, just make sure not to wipe off the black paint on the tube - this is called "aquadag" and it is important to the operation of the monitor.

[–] [email protected] 4 points 1 day ago

That's hot.