A 10¢ part kept this monitor from working

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#crt #apple
This Apple Color Monitor IIe turns on but has no image. Unfortunately, I didn't find any schematics for this set, so let's use logic to figure out what's wrong and get it working again.
Model A2M2056
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22 фев 2023

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Комментарии : 242

@yadabub Год назад

Your tester was going into calibration mode. You start calibration mode by connecting all leads together. That transistor was fully shorted.

@skonkfactory Год назад

a hinge that works by bending the material is called a "live hinge".

@volvo09 Год назад

Ah, I've always hated those.

@adriansdigitalbasement2 Год назад

Funny term for it! I'd never heard it called that.

@kentwobits Год назад

Live until it dies, am I right?

@darkwinter6028 Год назад

@@kentwobits ironic, isn’t it?

@Petertronic Год назад

It's living hinge on wikipedia

@xliquidflames Год назад

I have learned _so freaking much_ watching this channel and just listening to Adrian talk about everything. I still wouldn't feel comfortable working on a monitor like this but I did repair an Apple IIe using things I learned on this channel. Thanks for all the help, dude. This channel is an invaluable resource.

@BilisNegra Год назад

Congrats on that repair. That's awesome.

@xliquidflames Год назад

@@BilisNegra Thanks. :)

@Norstator Год назад

Time to bring out the rejuvenator. I'd love to see that thing in action again and see if it does bring back any emission.

@jeromethiel4323 Год назад

I remember when the NEC multisynch monitor came out. Without a video signal input, that thing would just whine at a super high frequency. It was so bad it would drive me out of the room. But with a good video signal, it was fine, because it was syncing to the video signal. But that monitor was a sign of things to come, as it would work with so many different video signals. Which eventually became the norm.

@hadessuk Год назад

“You can’t tell whether it’s a Hitachi” Neckring: JVC

@MattPlachecki Год назад

And a JVC deflection yoke! 18:12

@mrnmrn1 Год назад

Which is strange, because I don't think JVC had their own CRT fab. They used other Japanese brands, rebadged. Probably Hitachi was one of them, and somehow a yoke intended for sale to JVC ended up on a Hitach branded tube. I have two old JVC TVs, IIRC both have Hitachi tubes in them.

@MikesArcadeMonitorRepair Год назад

Fantastic! Love the monitor repairs...of course ;) EDIT: A suggestion when trying to adjust the image at the 44:00 mark, turn the brightness/contrast all the way down, turn the screen pot up until you get the retrace lines, turn the screen pot back down until the lines JUST go away, and leave the screen pot at that level. Then adjust the brightness/contrast/colors as needed. If it still looks dim at that point, then yes. The tube is weak. That's what I have found to be the best way to get the best results. The issue in the bottom right corner is likely bad/failing caps or the B+ regulation is incorrect. And yeah, bad caps won't affect colors or a weak image but they can cause oddities like the issue in the bottom right corner. I've even seen a failing flyback cause black blobs in the image as well.

@horusfalcon Год назад

Yup. This is pretty much universal for many models of CRTs. There are a few for which it doesn't work, though.

@briangoldberg4439 Год назад

i typically leave the brightness at the halfway point when doing this because if you put the screen pot at thr retrace point and the brightness is all the way down, you basically have zero adjustability in the brightness pot at that point

@cannotbeleftblank6027 Год назад

While you were talking about the various brands of chips and picture tube, you could clearly see 'JVC' on the yoke. So yet another brand to throw in the mix.

@cambridgemart2075 Год назад

That heatsink will not be connected to either mains line, it will be the negative of the rectified mains supply which will be at a high voltage relative to ground whichever way around the plug is inserted into the outlet.

@adriansdigitalbasement2 Год назад

I think the danger is it's still earth ground referenced, so if you touch it and you are grounded, it will shock you.

@cambridgemart2075 Год назад

@@adriansdigitalbasement2 Absolutely correct. My first experience of a TV set on the service bench using a chassis connected to B- was shocking, literally!

@TechnicolorMammoth Год назад

I absolutely love watching and listening to you work through these repairs. You’re the best, Adrian!

@davidellsworth4203 Год назад

Really nice to finally see you work on an Apple Color Monitor, even if it's a tired one. I based the color emulation of ApplePC (an Apple ][, //e, and //c emulator for MS-DOS) on this monitor - never owned one, but there were a few at my high school. It's so rare to see any of these in RU-vid. One thing I always wanted to do for ApplePC was take photos of images on the Apple Color Monitor to get some actual RGB values, and build a model of the effect of turning the Tint control, but I didn't have a digital camera at that point, and just had to go by my memory of what it looked like.

@jamesbennettmusic Год назад

if you want makeshift jigs to work on stuff, save / keep around rolls or parcel tape or the wide masking tape. Even keep the cardboard centers when they run out. They are a huge help to me

@Renville80 Год назад

Seems the (2S)C945 and the (2S)A733 were the all-purpose PNP and NPN transistors in Japanese electronics, much like the 2N3904 / 2N4401 and 2N3906 / 2N4403 in US-made products.

@jaycee1980 Год назад

Yep, exactly.... and us european guys tend to use BC546/BC556 for the same purpose :)

@garthhowe297 Год назад

That was a terrific example of tracing a fault. Loved the video!

@RudysRetroIntel Год назад

Nice save from the landfill! At least it was very cheap to get it working. Thanks for sharing

@shibolinemress8913 Год назад

I think my family had that monitor with our Apple IIe back in the day. I'm glad you got yours working again, even if it's no longer great, and it gets a well-deserved retirement rather than the scrap heap. 😊

@achubananoia Год назад

Another great video, thank you for sharing! I really enjoy your energy while you explain things.

@darkwinter6028 Год назад

“Hi, Tachi! How’s Mrs. Tachi?” 😜

@CaptainShiny5000 Год назад

Is the rejuvenator not an option anymore? I thought that you got a pretty good result on that one Apple monitor some time ago.

@pavuk357 Год назад

IIRC he dislikes rejuvenation even though he has all the necessary equipment. It just doesn't give you stable and reliable results and more often than not it will just completely ruin already bad CRT.

@kaitlyn__L Год назад

@@pavuk357 he’s also said he had better results with the simpler rejuvenator. From all the other such videos I’ve also watched, the kind where you just manually blast voltage for a fraction of a second does seem to be more reliable than the computer-controller multi-minute ramp-up on his most recent tester. But even then, the results don’t last, so it’s simply not worth the gamble unless it’s totally unusable. More often than not, a weak monitor gets made worse, so it’s a crapshoot.

@mrnmrn1 Год назад

This monitor is almost NOS, super clean inside, it shouldn't have a weak tube, especially since it's Hitachi, they made one on the most rubust, long-life CRTs. I have repaired/refurbished many dozens of CRT TVs and monitors, and seen hundreds of them inside, even the ones with half an inch thick soot-like black dust on every high voltage part often had a perfectly usable CRT, with sharp and bright picture. There might be problems with bad caps on the neck board, or increased leakage current of interstage coupling capaciors in the video or RGB circuits. It needs a CRT test, and if the tube tests good (it should), it needs a partial recap with all the electrolytics in the signal path replaced. And all of the dipped tantalum ones, too. ESR meter is not enough in cases like that to find bad caps, because increased leakage current can cause big trouble in high impedance circuits, and an (electrically) leaky cap might still have low enough ESR.

@vdivanov Год назад

Very nice troubleshooting! Thanks for saving the oldies but goodies!

@adriansdigitalbasement2 Год назад

Thanks for the super thanks! I passed the monitor on to a friend and even though it's worn out, he's happy!

@mattelder1971 Год назад

The term you are looking for about the hinge is "living hinge". It's really commonly used in flexible 3D prints these days. Same type of thing on some small containers as well (such as pill organizer boxes).

@Waltkat Год назад

Love your content. Even though I've worked with electronics as a hobby then making a living at it since the 60's, I always gain something from your videos. Just a heads up on the glue used to secure components to the PC board on a lot of older electronics. I've found that when the glue turns brown, they can sometimes become conductive, so if the glue is contacting multiple bare component leads such as capacitors, resistors, etc., it can short out that part of the circuit or at least cause enough leakage current to affect operation. I've fixed several devices by simply scrapping off the old glue. It can get so bad that you can actually measure the amount of conduction/resistance of the glue by using a multimeter.

@TheFurriestOne Год назад

Time for the CRT rejuvenator, maybe? Alternately, install it in a arcade cabinet with a IIc!

@Renville80 Год назад

I think that glue Adrian is talking about is a form of contact cement - vibration damage is a thing, and certain parts are tacked to the board to minimize the parts shaking loose over time (my company uses a relatively soft epoxy instead on the various products we assemble).

@BG101UK Год назад

This reminds me of one of the repairs in the workshop we had above the TV shop. A VCR with no colour .. like you, it took me a few seconds with the scope to spot the culprit, a 2SA1015 or 1018, can't remember exactly .. which cost a matter of pence. I'd had exactly the same fault on my (identical chassis) VCR prior to being in the service trade but as I didn't have a scope at that time, it cost me £40 at a repair place for a lazy board swap.

@CapnKetchup Год назад

My uncle gave me a bunch of vacuum tubes and his fixing kit. Among the goods was a square mirror that had an attachment that would fit a student music stand so he could monitor a TV picture via the mirror while he would be adjusting settings from behind.

@jeromethiel4323 Год назад

LOL! "Junk in the trunk" made me pause the video to have a good chuckle.

@hammeh-js2pk Год назад

Adrian, thank you so much for your repair videos! I always learn a ton from them, even when they don't go as expected. Something that I've discovered watching your videos, however, is that I can't really enjoy watching videos about 'nicotene infused' electronics. This is entirely my issue and nothing to do with you: My parents smoked like chimneys and I grew up with severe asthma and allergies as a result. Just thinking about that smell, even tangentially, makes my airways feel like they're going to close up. And that's okay. Not every video is for every person. Something I WOULD be interested in seeing, and I don't even know if this is possible, is a video about removing the tar deposits left by smokers on electronics. Like, is there a soaking treatment that wouldn't corrode or otherwise damage components? I'm absolutely looking forward to your next non-tar-covered video!

@darrenmurphy6251 Год назад

talking from the tv side of repair, the heater supply to the crt was never direct. there was always a series resistor or series inductor to drop the heater voltage down to the 6.3v or 12.6v (i cant remember what the heater voltage was) because the line output transformer supplying the heater was always slightly over driven to allow headroom for width and pincushon correction, you can short out that resistor or inductor to boost the heater about 5-10% to get the emission up then run it for 4 or more hours and sometimes if you are lucky that burnt off the cathhode poisoning and you can then remove the short. definately worth trying and it will definately not kill the heater because its a very small boost. there was a trade in little mains transformers with a 20% heater boost back in the 70,s through 90,s and those got left in permanently

@thehandygeek922 Год назад

I’ve been working on the newer version the A2M6021. That has a hitachi branded pcb with a Samsung CRT. I bought it not working as a project. What’s a pain with these monitors is there’s no schematics available. After replacing the fuse and fixing a crack in the pcb I got it powering the low voltage circuit. However it never displayed an image. I found a bad transistor and manage to find replacements. I swap that out last night and I now have an image. Albeit not clear, kind of pixelated. Color generally looks fine. I expect a bad cap or two is the culprit. That will be my next task. Your CRT videos have certainly helped me along. Thanks!

@cjripka6752 Год назад

Adrian, thanks for the great video! Christmas 1985, I was selling Apple //e and //c systems with the Apple Color Composite monitor. There was a high failure rate that resulted many of the monitors failing within 90 days of usage. It appeared to be the same component on most if not all of them. the warranty was 90 days in 1985. May were purchased 2-3 weeks before Christmas, so we had to appeal to Apple for exemptions, which they granted. I wonder if it was not this same transistor?

@michaelblair5566 Год назад

Adrian is one of the finest technicans I have had the privilege to watch!

@retropuffer2986 Год назад

Yay! Another Apple II monitor available for an enthusiast!

@terryraymond7984 Год назад

that reassures me on the main PCB staying in the lower voltage side I didnt know that thanks.

@elektro-peter1954 Год назад

Be carefull with those hot grounds,! There is allways voltage on them regardless of which way you plug in the plug, because there is typically a bridge rectifier making the "ground" live during the negative halfcyle of the mains voltage

@adriansdigitalbasement2 Год назад

You're right, it's after the bridge rectifier, and it's referenced to the mains so it'll be shocking no matter what. (Unless you have an isolation transformer, which I ran this on.)

@Matt-ys5ix 9 месяцев назад

Hey Adrian - The “flexible material hinge” is called a “living hinge”. Love your content…never thought I’d be able to contribute to these discussions. 😎

@jeromethiel4323 Год назад

Every electronics hobbyist should have a junk box. Nothing beats having a ton of parts at hand that you can scavenge for testing or building things.

@xliquidflames Год назад

This is the exact monitor I had on my first computer. When my elementary school upgraded their computer lab in the mid 80s, we were given one of their old Apple IIes. My obsession with computers started around age 8 in the mid 80s because we had this computer in the house for me to tinker with. I learned to type and program on that computer. I was the only kid in middle school that could properly type. I had a free period in the 7th grade because it was supposed to be a typing class and I aced the final exam in the first week. I have fond memories of playing Number Munchers, Oregon Trail, and Where In The World Is Carmen San Diego on Saturdays instead of watching Saturday morning cartoons.

@bobweiram6321 Год назад

"Where in the World is Carmen San Diego" eventually became a Saturday Morning Cartoon. LOL!

@xliquidflames Год назад

@@bobweiram6321 It was also a live action game show on Nickelodeon, I think. Nickelodeon or Disney.

@David_Ladd Год назад

Great video! Yeah even if it was dim I would use it. I would use it mainly for the 80-column text.

@freeculture Год назад

Looks good enough for those games, that computer isn't high res anyway, the blurriness actually smooths the edges 🙂

@tigheklory Год назад

Adrian if you have a rejuvenator you can use it to test the guns to see how tired the guns are. I wouldn't count the CRT as bad until you test the CRT isolated from the chassis. It is so easy to test. At least on my Heathkit. Also you can do a cleaning of the guns while you are at it. Did you notice that the yoke as a JVC logo on it? #ColecoAdam

@joesaiditstrue Год назад

I believe he has an old rejuvenator from the 1960s? he's used it in a few videos, odd he didn't mention it here, he didn't seem to like using it from what I remember

@tigheklory Год назад

@@joesaiditstrue my Heathkit is much newer, is his really from the 60s? There weren't a lot of color TVs at that time.

@joesaiditstrue Год назад

@@tigheklory Yeah search RU-vid for 'Adrian Basement 1969 Macintosh' and you'll see it

@Hogwarts.Failure Год назад

Not only causes the black goo of death corrosion but i gets conductive too, KRK studio monitors sufferd a lot due to this glue. i repaired hundreds off them.

@dglcomputers1498 Год назад

There used to be the issue back in the day when repairing old TV's, a lot of them had live chassis and required an isolated aerial socket, problem was a lot of repairers didn't realise about that or didn't care, potentially you could then get an energised aerial socket and a massive shock risk. Multi outlet aerial installations are supposed to have the shields connected to mains earth at the splitter/amp to protect against an energised aerial socket/RFI capacitor leakage, the only exception is a multi outlet satellite setup where the feeds come directly from the LNB on the dish as they are, in theory, already isolated so one rogue device should not be able to energise the other feeds.

@therealjammit Год назад

I think it's possible for the first PNP transistor you tried had the "C" and "E" backwards. Many low voltage transistors will still "work" with the "CE" swapped but it'll have really poor gain.

@tw11tube Год назад

Indeed. While the gain is bad, the collector-emitter saturation voltage is extremely low in that configuration. Before we had good MOSFETs to short things to ground, bipolar transistors with low satuation voltage were used to short an audio signal to ground as "mute switch". There are transistors that have the "reverse operation" mode explicitly specified in the data sheet, and often times "mute switch" is one of the recommended applications pointed out on the title page of the data sheet.

@eDoc2020 Год назад

Those little AVR transistor testers have no problem determining the proper lead configuration. The gain was fine, the problem was the bandwidth.

@sivalley Год назад

@@eDoc2020 This. Just because it's rated for up to 200MHz switching frequency doesn't mean its slew rate wasn't in the toilet

@ILikeMetricMusic 6 месяцев назад

I remember using an Apple color monitor with the composite video input with the NES growing up. I remember how clear the graphics looked to me 😊

@tony359 Год назад

Nice! I also worked on a CRT where the board was caged into a metal shield and it was a nightmare to disassemble every time! I have some Apple //c small ones to fix soon, I guess those are going to be demanding too! What was that issue on the bottom right of the screen in the end? Did I miss something or it just disappeared?

@ricardog2165 Год назад

Adrian don't forget to try your CRT rejuvenator!

@KING_VHS 11 месяцев назад

that pick looks like the one of four from a set at Harbor Freight Tools... good choice of picks.

@ofoehr Год назад

Adrian , you can do things like that verry short. Take an > 10k resistor , one end to ground one end to the transistors on the neck board. on the head think or better known as collector. The picture tube will show you the max what is possible. Play around wit the resistors , lower resistance more intensive beam.

@marka1986 Год назад

If the mains uses a bridge rectifier the live side of the chassis will be about 70 volts hot no matter which way you plug it in. Most consumer electronics used a 2 prong cord, sometimes polarized, sometimes not. It was up to the tech to do a leakage check on all exposed metal parts accessible to the customer after the unit was reassembled. The test can found described on the back page of almost every SAMS photofact.

@myusernameisrighther Год назад

That thing you described as a little floppy piece of plastic as the hinge is called a living hinge. They suck really hard because they work harden. So they don’t tend to last very long.

@DavidRavenMoon Год назад

Your chassis ground is connected to the third pin on the AC plug which is missing. So no ground for you. AC neutral is not ground.

@bhhenry Год назад

My neighbor asked me to post this comment because their internet went out: "Wow, great video, Adrian! I love watching you work on these old monitors, but I have to say, my attention was a bit divided during this one. Did anyone else notice that cute little kitty that kept sneaking into the frame? I swear I saw a flash of orange fur just off camera a few times. I'm a huge cat lover, so I couldn't help but get distracted by the possibility of a feline friend hanging out with you while you work. Anyway, back to the monitor restoration... Oh wait, there it is again! I swear I just saw it walk by. It's such a shame we can't see the cat on camera, I'd love to know if it's a stray or if it's your pet. Maybe you could do a video introducing your furry assistant to your viewers? But seriously, great work on the monitor restoration. It's always fascinating to see how these old pieces of technology can be brought back to life. Keep up the good work, and give that kitty some scratches behind the ears for me!"

@davidhollfelder9940 Год назад

Back in the day, the color burst was said to be on the “back porch”. As Shango says, the CRT is “BAKED”😊

@Lachlant1984 Год назад

I'm in Australia and I've used a few Apple IIE Platinum computers, most of which had monitors that looked like this one, I don't know what model they were though, and I don't remember which control panel door they had, but they did have the same arrangement with the power on light and power button, and I also remember at least one of them having the Colour/monochrome button. I presume they were PAL, but I don't know for sure, at the time I used these computers I knew what NTSC and PAL were, but I wouldn't have know if that affected Apple II computers.

@patprop74 Год назад

30:41 I have that exact same tester, had it for years, and never really had a problem with it, however, if you would like an OLD SCHOOL transistor tester, lol I do have a KB 520B transistor tester that is not really being used.

@branhicks Год назад

We had that exact monitor in my 3rd grade class. I remember it had really weird color. I was so close to getting the VCR hooked into it once to see what it looked like but the teacher caught me

@anthonydenn4345 Год назад

Nice job repairing this. Do you think maybe the terrible image is a composite thing. The width looks a little off too, going by the narrow colour bars on the sides.

@SonicBoone56 Год назад

Welcome back to Frank's Analog Attic!

@adrianoacquaviva7570 Год назад

And talking about different brands, there was also a JVC on the plastic ring around the tube...

@Sobakin76 Год назад

BC556/557/558 in your transistor kit are PNP and could be OK for replacing KSA773. As well as BC327 which is maybe too powerful for this and has higher undesirable junction capacity.

@m2esectr Год назад

Yes, I'd be happy to use this monitor in this condition, just cleaned up to get rid of the cigarette smoke residue and smell

@chuck2501 Год назад

can you lock the exposure on the camera and try and fix or kill the CRT with a rejuvenator!

@tarzankom Год назад

I have the exact same Harbor Freight Phillips screwdriver.

@rottmanthan Год назад

mine has the flexible plastic hinge, but thankfully its still good.

@vhfgamer Год назад

It seems like ever single monitor that passes in front of Adrian is "too dim" or "worn out" or "not usable". Meanwhile I'm sitting here looking at the jacked up inferior image that the camera provides, which is a pale shadow of how good it really looks in real life... and I say it looks fine. Use it.

@_droid Год назад

Gives me some ideas for a 1084 I'm trying to fix. Almost the exact same symptoms. High voltage, flash when turning off, etc. but just a black screen no matter which input I use. I've been tracing the lack of signal backwards from the tube to the chips. I probably need to go the other way like you did.

@CeLrRaC Год назад

This kind of monitor deserves to be repaired at 100% It would be very funny if another tube swap video is produced, but before it, another rejuvenation attempt is made. Only for fun. 🎉😊

@tim1724 Год назад

Some of the monochrome monitors (Monitor // and Monitor ///, I think) have schematics available but I don't remember ever seeing schematics for any of the color ones.

@adriansdigitalbasement2 Год назад

Yeah some have leaked ones, others have SAMs (third party) schematics but none were ever made for the color ones.

@terryraymond7984 Год назад

I hope that monitor will live again its in good hands

@jkeelsnc Год назад

For safety reasons I think I would replace the AC plug with a new 3 prong grounded plug.

@kjamison5951 Год назад

It might trigger the purists… Sheesh! FWIW, I would swap the existing plug for a safe one with a ground pin.

@3osufdh4rfg Год назад

@@kjamison5951 Maybe make a short extension cord with the proper three pin plug on and plug it into that and duct tape it in place?

@mrnmrn1 Год назад

@@3osufdh4rfg That would sort the Live-Neutral reversal, but there would be still no ground connection, and the monitor needs it...

@eDoc2020 Год назад

I would consider adding an IEC inlet socket on the back. A detachable power cord is more convenient, and you also wouldn't need to clean the old cord.

@808v1 Год назад

I'm assuming if you had removed the bad transistor first and tested the emitter on the first one the correct video signal would have been present? Since the next transistor was shorted the connection between the 2 was shorted - emitter on the first was shorted until you broke the connection by removing the shorted transistor.

@mrbi1198 Год назад

that's called a 'living hinge'

@trancedude330 Год назад

I would have started by changing the mains connector with one that had the earth prong, otherwise awesome vid

@frugalprepper Год назад

Can't you use your CRT Rejuvenator on it?

@rpavlik1 Год назад

Oh man I remember some of these from computer labs at school...

@JVHShack Год назад

After watching this and seeing a similar problem with a composite video monitor with audio that I have, I'm wondering if it has the same problem. I get no image on the screen, but the audio works perfectly in my unit.

@UpLateGeek Год назад

Not sure, but most Apple IIs I saw here in Australia back in the day just had a monochrome monitor, so I suspect they were just NTSC models. A while back I bought a clone, which didn't come with any cards, and I'm pretty sure that's just an NTSC model. I haven't got it working yet, but I did buy a PAL card for it to see what the difference is. Unfortunately the only CRTs I've got that take a PAL or NTSC input are my PVMs, which are all in storage at the moment. So running either a PAL or NTSC signal through my scan converter to run on a VGA CRT or LCD probably isn't a good for comparing image quality between PAL and NTSC.

@Quickened1 Год назад

That was an awesome repair! I would have loved seeing the voltage on that heatsink when the mains cord is plugged in backwards. Was also interested in knowing if the high voltage dropped into the 15kv range after you replaced the transistor? That blob disappeared from the lower right corner, did you do something to repair that, or is it still there, and I just couldn't see it? Wish I would have received this kind of knowledge 40 years ago! 👍

@eDoc2020 Год назад

I have a hunch the power supply uses a bridge rectifier. If that's the case the voltage on the heatsink will be ~60 volts to ground no matter the orientation of the plug.

@kardRatzinger Год назад

I believe the typ of hinge made of a thin piece integral with whatever two parts are being hinged is called a live hinge.

@GodKitty677 Год назад

CRT monitors give the best electric shocks. The little rubber cup thing at the top of the back of the screen is great fun, upto 25k volts there (forget its name). The reservoir cap in the power supply is fun too. The other issue is the CRT has to be on to troubleshoot.

@8BitNaptime Год назад

The anode cap? Yeah that must be great fun. I usually carefully insert the tip of my high voltage DC probe under there and when I hear the snap! of the arc I leave it there just to be sure.

@kaitlyn__L Год назад

Thanks for the right giggle, “great fun” is one way to put it that’s for sure!

@rommix0 Год назад

Look guys. We have ourselves a bad ass over here who is also a shock connoisseur. I'm baffled that you are still alive.

@GodKitty677 Год назад

@@rommix0 You should see the students getting a belt by not listening to the teacher and touching stuff without decharging it correctly. You are correct, it's up there with people who lick electric fences for RU-vid videos. Never do that crap twice.

@eDoc2020 Год назад

I've unplugged the anode connection on a running TV and yet I've never gotten shocked by a CRT high voltage supply. On the other hand I've gotten shocked by the "low voltage" supply in the same TV several times. But that was mostly through carelessness when moving the chassis.

@SonicBoone56 Год назад

Even though the CRT is worn out and tired, it's probably still good enough to not go into ewaste, right? I'm sure it'd be of use to somebody.

@andywest5773 Год назад

It might have been used in a school... in the teacher's lounge. 😁

@MathijsWijers Год назад

Me and my weird mind... @4:09 "Of course this is an NTSC monitor, released in the US a 110-120..." Me immediately branch predicting the words " years ago"... :P

@Gubalicious Год назад

The thing he says about a finer dot pitch requiring higher driving of the brightness and contrast and quicker degradation of the tube. Is this applicable to most/all PC CRTs? Because I have a few PC CRTs that have nowhere near the number of hours of a consumer set and have distinctly dull tubes. I have an NEC XE21 20 inch with 13000 hours on the clock and is close to being scrapped as the picture and the emissions on the tube are just so dim. Same for a 17 inch Trinitron E250, it saw use back in the early 2000s as a gaming monitor but nowhere near what a consumer set would get. Again same for a Philips 201B40, with 2500 hours on the clock. I have to crank the colour levels to get any vibrancy out of it. The manual for this states a normal lifetime of a monitor is around 10000 hours which is interesting. It works out to just under 5 working years for a monitor if used for 8 hours a day (not at weekends). The default setting on the last 2 are something like 80% contrast. When you crank it up to full there is little difference. Compare that with a Trinitron 21 inch consumer set that has 15000 hours on the clock and is still vibrant and sharp at just over 50% contrast. I see plenty of youtube videos and reddit posts with people showing old PC CRTs that have nice bright and vibrant pictures. So I don't know what the rules are. Those monitors must be barely used.

@pkneeyahx Год назад

When I started college they had just instituted no smoking policies. The classrooms and hallways had wallmounted ashtrays. So this monitor could very well have been in a university or college...

@apl175 Год назад

What happened to that nifty tube rejuvenator?

@wowtechniplex Год назад

Do you have a CRT rejuvenator? I have had some good success with one.

@kencreten7308 Год назад

First thing I see - DUNG BEETLES. I've never played that. I wasn't early game player, even though old. That's a weird name for a game.

@rommix0 Год назад

I don't which would be weirder. The Dung Beetles or the Rolling Bones.

@ChrisBrunner Год назад

If you're looking for a home for that monitor, I'll gladly take it off your hands for my Apple //e setup. All I have right now is a monochrome Monitor ///. I live in Portland. Love your videos!

@terryraymond7984 Год назад

so thats the raster as long as the screen in lit is the Raster?

@belzebub16 Год назад

Might that one not be a good candidate for rejuvenation? Nothing to lose here at least 😊

@malcevans5762 3 месяца назад

Give the tube a blast

@bobbofly Год назад

The single piece flap hinge you described is what's known as a "live/living" (either term is correct) hinge. or, in my personal parlance, a "POS." Oooh, the alliteration... 🤣🤣🤣🤣🤣🤣 As you pointed out, they ironically don't live long. ✂

@jeromethiel4323 Год назад

Never rely on your electrical plugs to be wired correctly, unless you have verified them. People who are not qualified to hold a screwdriver do electrical work. It's your life, proceed with caution. I've seen plenty of mis-wired outlets in my life, and i am not even a residential electrician.

@danyoutube7491 Год назад

@9:44 Adrian is talking about the glue that, over time, starts absorbing moisture from the air, and wonders if the correct term for this is hydroscopic. It's actually hygroscopic. I mention this only because until ten minutes ago I had never heard the term before; my dad was talking to me about car brake fluid which is also hygroscopic. When he said it I thought I'd misheard, and I said "hydroscopic?" :)

@terryraymond7984 Год назад

What is that on the top right side looks like the fuzzy part of Velcro