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The Secret Life of XY Monitors (2001)

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Re: The Secret Life of XY Monitors (2001)

#51

Post by xcv123 »

autoexec wrote: post #31
kjkjadksj wrote: post #29

Earlier quoted context omitted.

Lcds were way better than the crts consumers had. Most desktop crts were absolutely massive and took up the entire desk. We had to install special drawers in our desks that slid out and held a keyboard because there wasn’t room otherwise on most desks. The lcds that replaced them were far lighter, my grandparents could actually move them for once, they took up probably three inches of the desk, and they were bigger d…

LCDs were garbage at just about everything. It was so much worse when the screens were new, but even today I have yet to see an LCD screen that can display an image with even a single solid color accurately. Correctly representing an image on a screen is their one job and they still fail at it. See my reply here ( https://news.ycombinator.com/threads?id=autoexec#39670782 ) for a list of just some of the ways LCD scre…

> even today I have yet to see an LCD screen that can display an image with even a single solid color accurately

Have you tried professional calibrated monitors? https://www.eizo.com/products/coloredge/

Re: The Secret Life of XY Monitors (2001)

#52

Post by c22 »

kjkjadksj wrote: post #26
RetroTechie wrote: post #14

It's a pity such monitors aren't made any more. In the late 80s, I owned a small (12..13" or so) amber monochrome CRT monitor. Lovely phosphor color, non-flickering superb for text-based work, single composite video input. Let go when it didn't seem to matter much, and CRTs were still everywhere. But today I'd love to have such a screen. Commercially this would be a small niche market, but probably a stable one. And…

I turned on a crt recently and it was so noisy I could hear it outside, through the walls. My cat ran and hid. Did we really all collectively just tolerate that noise back then, or do these things decay over time somehow and get louder?

You couldn't hear it over the sound of your PC fans and hard drive seeking...

Re: The Secret Life of XY Monitors (2001)

#53

Post by LorenPechtel »

onetimeuse92304 wrote: post #3

> It's also a safety issue, since the Cathode voltage might be substantial. When I was a small kid, my father had a TV set repair side hustle. I was 7-8yo but I would sometimes be called to help him a bit. Once he asked me to clean a bunch of CRT tubes from substantial amount of dust. What he forgot is that he was just testing one of them and the charge wasn't properly dissipated and it did not have time to dissipate…

I got zapped once as a kid. My grandfather's TV, I was pulling the tubes to take them to the testing machine. Fairly small screen but I knew it probably had some residual charge that I most definitely didn't want to come into contact with. The layout was such that I could pull the tubes while staying far away from it. It never occurred to me that safety would require keeping him from looking on in curiosity and bumping my arm. (He was impatient about getting his TV fixed, I saw that whoever designed it had had the courtesy to put the tubes in an area where even if your hand slipped it wouldn't approach the tube. That was no protection against my hand getting moved in a direction I was not applying force, though.)

I don't think such things are actually capable of direct lasting damage but you do lose control--I slammed my hand into the cabinet pretty hard, completely involuntary. My understanding is that tasers are AC, thus involuntary movements will be back and forth rather than just in one direction.

Re: The Secret Life of XY Monitors (2001)

#54

Post by HeyLaughingBoy »

kjkjadksj wrote: post #26
RetroTechie wrote: post #14

It's a pity such monitors aren't made any more. In the late 80s, I owned a small (12..13" or so) amber monochrome CRT monitor. Lovely phosphor color, non-flickering superb for text-based work, single composite video input. Let go when it didn't seem to matter much, and CRTs were still everywhere. But today I'd love to have such a screen. Commercially this would be a small niche market, but probably a stable one. And…

I turned on a crt recently and it was so noisy I could hear it outside, through the walls. My cat ran and hid. Did we really all collectively just tolerate that noise back then, or do these things decay over time somehow and get louder?

Slap it on the side. Coils may be loose due to age and glue drying out.

Re: The Secret Life of XY Monitors (2001)

#55

Post by gwbas1c »

autoexec wrote: post #15
RetroTechie wrote: post #14

It's a pity such monitors aren't made any more. In the late 80s, I owned a small (12..13" or so) amber monochrome CRT monitor. Lovely phosphor color, non-flickering superb for text-based work, single composite video input. Let go when it didn't seem to matter much, and CRTs were still everywhere. But today I'd love to have such a screen. Commercially this would be a small niche market, but probably a stable one. And…

When LCD monitors/TVs came out they were a huge step backwards in terms of quality. They were relentlessly pushed on consumers because they were cheaper to make, cheaper to ship, and took up less space in stockrooms and on store shelves. I doubt the CRT will make a comeback. Even today's TVs are inferior to CRTs in some ways and so we're still compromising, but at least current LCD screens are so much better now than…

> Even today's TVs are inferior to CRTs in some ways

Get a high-end OLED. Totally exceeds the real and imagined advantages of CRT.

Re: The Secret Life of XY Monitors (2001)

#57

Post by HeyLaughingBoy »

dn3500 wrote: post #27

I used to have a 1948 Hallicrafters TV and it had yet another type of high voltage supply. There was a 100 kHz oscillator driving an air-core transformer in normal (not flyback) mode. The potting had gone bad on the transformer, and I couldn't find a suitable replacement, but I did find one that had the right secondary winding. Since it was air-core I just cut the secondary off that and the primary off the original a…

Hallicrafters made TVs? I guess I shouldn't be surprised but I've only ever heard that name in the context of ham radio and shortwave listening.

Re: The Secret Life of XY Monitors (2001)

#58

Post by renewiltord »

close04 wrote: post #10
onetimeuse92304 wrote: post #5

Earlier quoted context omitted.

Well... one difference between a stun gun and CRT tube is that in a stun gun you usually have both terminals relatively close to each other. Little chance of the main pulse going deep across the chest. On the other hand working with the CRT you are likely using both hands and that makes the signal go through your upper chest, by default. So yeah, there is something to it. One thing I learned as amateur EE is to alway…

> One thing I learned as amateur EE is to always use just one hand to probe the device under test I was taught to use the back of my hand to avoid gripping the damn thing and never letting go.

Same. And I do it like a superstition now.

Re: The Secret Life of XY Monitors (2001)

#59

Post by TFortunato »

sowbug wrote: post #9
Scoundreller wrote: post #7

Earlier quoted context omitted.

And have someone nearby with a 2x4 to beat you off whatever you might be gripping/fell onto.

Just to add a bit more color here: most flexor muscles in your body are a lot stronger than the corresponding extensors, so when an external command comes in telling both to contract, for example from electricity in the thing you're working on, gripping wins. You can't let go. Great for grabbing a branch as you fall out of a tree. Not so great for repairing a power line. Late edit: I've heard you can use this factoid…

Related fun fact - On many industrial robots that I've worked with, the teach pendant (the handheld controller you drive it around with), requires you to hold a 3 position spring-loaded switch in a middle position for the robot to operate, which requires you to hold with a rather precise amount of force. Squeeze it either too loosely or too tightly and the robot disables.

The idea being that not only will you dropping the pendant disable the robot, but it will also disable if you accidentally touch energized equipment and your hand clenches, or (more likely) you panic and squeeze the controller too tightly.

https://us.idec.com/idec-us/en/USD/Safety-Components/Enablin...

Re: The Secret Life of XY Monitors (2001)

#60

Post by onetimeuse92304 »

dmoy wrote: post #50
onetimeuse92304 wrote: post #5

Earlier quoted context omitted.

Well... one difference between a stun gun and CRT tube is that in a stun gun you usually have both terminals relatively close to each other. Little chance of the main pulse going deep across the chest. On the other hand working with the CRT you are likely using both hands and that makes the signal go through your upper chest, by default. So yeah, there is something to it. One thing I learned as amateur EE is to alway…

> One thing I learned as amateur EE is to always use just one hand to probe the device under test if there is any high voltage or AC involved. I remember in some EE course, the prof randomly stopped in the middle of a lecture and said roughly "Ok now that you all know this theory, I need to remind you that you should not go do your own home electrical work, because you will get ahead of yourself and die from some kin…

I did not mean doing home electrical work. That I do leave to professionals.

But there are times I have a device on my bench that is consuming 230V AC.

I have a 3kVA separation transformer set up, which makes it safer for me to work with the device (there is no potential between the DUT and the ground).

Technically, even without the transformer the residual current protection should kick in and prevent you getting killed between device and the ground. I have tested mine couple of times to check whether it works. But I somehow still feel better with a separation transformer.

But there is still the problem that I could touch different parts of the device that are at different potential and then I could get zapped this way. There is not much protection there. Solution -- If you must, don't ever touch more than one place at a time.

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