IBM 5153 CGA Monitor Simple Recap
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- Опубліковано 22 жов 2018
- A "spurt" sound isn't something you ever want to hear from your monitor...
I knew I wasn't going to get away with leaving it shifting between blue and red for long, but I didn't think it would be this short.
If I had seen the cap on the connector board for the CRT initially then I wouldn't have had to take the whole thing apart. But I kind of wanted to get an overview of what was going on inside anyway so I don't mind the extra work having been put in. But if yours blows a color cap you can easily avoid the most difficult part of removing the tube.
I'm happy with how this turned out. I will be getting better capacitors later for it, but it isn't a rush. I think I made all the colors a bit dim on the adjustment on the back of the tube. That's probably why it seemed so much darker afterwards. Really, I should have done the calibrations at about 75% brightness. Oh well, it's not too difficult to get to that so I can always fix it later.
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Re: discharging, you need to use a screwdriver with a plastic or resin handle, not a rubber handle. You're getting zapped through the screwdriver because the resistance of the screwdriver insulation is fairly low. Go to Harbor Freight and buy a long, cheap screwdriver with a plastic handle and turn it into a permanent discharge tool by wrapping a stripped wire around it a few times and installing an alligator clip on the other end. Tape up the shaft to hold the wire to the screwdriver (maybe even try soldering it... it might work).
I love your videos because it shows all the hell and failure that can happen while repairing these old systems. Sometimes it is frustrating when you see a video and everything goes right and just works. It never works that way.
There are two high voltage leads in that monitor. One is the supply from the flyback to the anode, the other goes from the anode to the focus block. That's the big white thing with a knob on it. It taps the 25kV through a HV pot to get the ~8kV for beam focus and convergence.
Being a variable resistor, the focus block discharges the tube soon after it is turned off. You won't get much if anything at all when you try to discharge the tube.
Since this seems to be the theme of the comments so far I'll mention something about "grounding" the CRT.
You aren't actually "grounding" the CRT in the sense that you are connecting it to earth ground. That does nothing. What you need to do is short the CRT. The CRT itself acts as a capacitor and you are trying to "burn off" any charge it has. Connecting the anode and cathode(which is always connected to "ground" in circuit) will short it. So having mains earth connected is not part of the current loop whether it is connected or not.
CRTs "should" have a bleeder in circuit that discharges the tube when it's powered off. But that is functionally optional, so I would never trust any tube to have one.
what the hell did i read? a chassis full of electrons searching a way out? so a chassis holds a charge?are you delusional? thats not how electricity works dude, the electrons FLOW because of potential difference...the chassi is at zero potential and so are you...by that line of thinking applying 220v to a steel bar would leave it full of electrons trying to escape....manufacturing of batteries would be so so easy....DAMMM copper wires would shock you all the time even disconnected...
Dude i know nothing about cooking so i dont comment on kitchen videos...you know zero about electricity so dont comment here ok?...dont mislead people please..its for everybodys safety...And speaking French doesnt make you smarter ok?
once you short the crt's anode cap to chassis there will be no voltage in either part... the crt acts as a very small capacitor ( maybe 20pf or so) because of the aquadag outer coating and the anode inside of it, the glass acting as the dielectric...the current will be very very small but the voltage is maybe 10kv on a black and white and maybe 16 or more in a colour crt. since the current is very small it probably wont kill you if you are healthy but it will zap you and it hurts a little..you will jump back and may get hurt on the glass or in a tool, you may trip and fall and that is the most dangerous...i have been zapped a few times....once you short it to the chassis it will discharge...end of story.... electrolitic capacitors and others on the board MAY in rare occasions hold a charge (poor designed circuitry) ...you can also discharge them with a resistor or by shorting them but i repair tvs and never needed to do so...usually there is dc path around the capacitors through a resistor or inductors etc and they self discharge
If you do ended up doing a full recap, is there any chance you could bung up a list of caps required? I have a dead 5153 myself, and a list would be fantastic.
Let's say that there is 20kv difference between anode and cathode of tube. When shorted you will have 10kv on both sides in reference to ground -if you don't use a resistor. Now we touch it and you get your 10kv jolt. So, please use a resistor and connect tv to real ground.
Voltage is an electrical potential between two points when there is a current path. The anode of the tube could be 20kV in reference to the cathode(which is connected to circuit "ground"). When you short across the capacitor by connecting the anode and the cathode you bring the two to the same electrical potential. Thus if you referenced the anode to the cathode you would see 0V.
Mains ground is not a component of the equation. When the CRT is not connected to the mains there is no current path. So any electrical potential between circuit ground and mains ground is non existent.
AkBKukU, you may still get a zap if you are at a different potential to the monitor chassis... I suppose you might mitigate this by grasping the chassis while you are doing the discharge, but I think it would probably still be safer to connect the chassis to earth.
Those are some nice macro shots you got of removing the bad capacitors. I'd imagine that those were a pain in the butt to remove with the camera in the way.
You might enjoy seeing this: twitter.com/AkBKukU/status/1052575518174851072
@@TechTangents remember that if you don't have good 240v capacitors... you can use two of 120v in series
is the same criteria that you apply for batteries..
if you don't get a 24v battery.. you can put two of 12v in series ...
if you can't get 60 amp of "capacity" batteries .. you can put two 30 in parallel
...
with the caps.. is the same
criteria ...
if they don't get 5000 microfarads... you can use two of 2500 in parallel...
ALWAYS SAME VALUE both of them..
and of course for resistors ...
every single value that is not manufactured..
is because it is obtained by mixing those that are manufactured.
.
For example ... 50 ohms does not exist ...
because it is obtained with two of 100 in parallel
...
7.8k does not exist ... because it is obtained with two 3.9k in series...
30ohms does not exist ... because it is obtained with 3 of 10ohms in series...
500ohms does not exist ... because it is obtained with 5 of 100ohms in series...
OR with 2 of 1K in parallel
and like that .. for every other value...
@@Ramdileo_sys Stacking capacitors is a really silly idea, though.
@@miko-nv9cl.... ha! .. tell that to Tesla Motors that is Stacking like a thousand of lithium capacitors to make the battery of their cars............ In serie.. ok.. maybe.... you know, it will work until one of them begins to differentiate from the other.... and then one of them it will start to overcharge and... yeah.... so it is more like a temporary thing.............. but in parallel they are used everywhere..... the anode sheets of both will be working as one..... same with the cathode sheet..... so they wear out together as one...... You see it ..again.. with lithium batteries (which are basically very low self discharge capacitors)..... one or more of the cells in series fail.... but those that are in parallel... are always with exactly the amount of wear.. like identical..
For future calibration, there are many monitor color and geometry test patterns built into "The CGA Compatibility Tester" which runs on 5150s and compatibles.
You might be right on the "half pound of flux" theory. I'm in the middle of working on a Yamaha amplifier from the late 70s, and the boards look very similar.
8:49
Just looks like flux from the wave-soldering bath. It was quite common to see that on boards back then.
Most flux (especially the old-school stuff) is supposedly slightly corrosive, which is the whole point of how it helps clean the solder joints.
Maybe it's not always that bad, though, and rosin flux is just tree sap after all. It's lasted pretty well for over 35 years, unlike most modern electronics. :p
I've only ONCE ever had a slight zap when discharging a 28" colour CRT, and that was only because my makeshift ground wire wasn't securely attached to both the chassis and screwdriver, nor was the screwdriver properly insulated with tape.
A lot of screwdriver handles have a high carbon content, btw, or just aren't very good insulators.
I'm not sure why people suggesting that you need to hook up the discharge tool to mains Earth, btw? That's just plain wrong, sorry, and possibly dangerous.
The whole point of connecting to the CRT chassis ground is that you're then shorting directly ACROSS the tube, since the tube itself forms a high-voltage capacitor.
If you try to discharge the tube to mains Earth, it will still likely arc over to it, but by no means will it guarantee fully discharging the tube, since there's no complete circuit for the discharge current to flow.
The resistance across the CRT needs to be as low as possible, ie. a direct short.
I've safely discharged hundreds of CRTs over the years, and never seen anyone ever connect to mains Earth nor a separate grounding point.
(not even seasoned repair people, nor arcade maintenance peeps.)
Great vid man! For a second, I thought I could smell that solder! I don't know what was more impressive- the fact that you're able to use the vacuum desoldering tool ("Solder Pullit!") and it actually works for you, or that you were able to film that so effectively so that we could actually see it. Well done, sir!
Visitor from 2022 here.... Sad Fry's is gone, but them and RadioShack are (were?) the convenience stores of the electronics world. You got a sorta functional part but you paid a premium price for not having to order it in by mail. We have a place called you-do-it that sells NTE parts, they bailed me out plenty of times when I needed a part TODAY. I hope the monitor continues to work well! I love your videos!
Excellent video there man!
I recommended it to one of the guys from the Retromachines group on FB who has a similar problem with his 5154. Thanks for helping out the community 👍
Just picked up of these myself, here in the UK, so this is a great help to me. Thank you!
Monitors have so many variables to them. It's interesting to see the troubleshooting involved. Adrian Black has some great videos on his channel on this sort of thing too.
At school, I'm trying to repair an Olivetti m24 on my own(an Italian ibm clone called AT&T 6300 in US). I once opened a printer that was compatible that used to collect dust at school and WOW it was dirty. I couldn't see the color at all. Your screen in comparison was almost beautiful! Very nice video!
>simple
>31 minute video
Yeah, it's simple alright.
Yeah, I threw "simple" in the title after I realized this. The real repair should have been simple. But I made it more complicated for myself.
Well.. simple, not short actually. It was REALLY well detailed, so i guess the title is fair.
You should see johns arcade. 2 hour recapping of arcade boards IN REAL TIME if you think this is long!
man it takes me hours to do a recap so faster than me i guess
@@TechTangents that's why you're druaga2
Thanks for the lecture on capacitor datasheets.
I subscribed at "aaand here's where it wet the bed"
The "no clean" flux they used in those days just left a lot of residue. It was harmless on the board. When soldered in the quantities used at the factory though it could cause some lung issues.
Love your repair videos man, had me nervous when you where discharging that CRT :)
Nice job filming the close-up of desoldering! A good look at the board...
Nice video as usual! Liked how you compared the datasheets comprehensively, I would have missed quite a few of the dodgy details, good to know when buying caps! I'm lucky to have Panny low ESRs and similar caps available locally, and for a reasonable price, so I just use them every time. It surprises me how difficult it seems to be source the good stuff locally in the US, and they put them in those oversized and wasteful boxes! Though I'm guessing it depends on the city...
I wish they still made CRT screens. Imagine how good they could make them now with modern technology.
Pretty much exactly as good as the best ones were back in the day they were made I suppose... why the hell would you ever want one?
Better colors and contrast than a TN panel. And they can run at any resolution without aliasing and blockiness. Also they have instant response time. And no they wouldn't be the same as the best ones back in the day. We could make them way better now, higher reseolution, better definition, longer life etc.
"Better colors and contrast than a TN panel" is a pretty dud argument since we have many flatpanels way better than TN available. If you are going to compare against the cheapest LCD tech then by all means compare the cheapest dirtiest CRT tech out there at least. "any resolution" is not really true either, CRTs are rather limited in the upper end of resolutions newer panels can reach. Response times for current screens are way beyond any human perception. I really don't see what tech could have progressed much to make better CRTs except for the same digital processing which is already improving images on modern screens. If you happen to like a blurred uneven and geometrically distorted picture over a "perfect" one given by say a modern OLED then that's just a matter of taste. Same as someone liking the sound of LPs better than very hifi digital audio. There's always room for opinion. I'd say that CRTs did what they needed to do and had some advantages back in the day of low resolutions (natural blurring etc. helped to reduce the blockiness of very, very large pixels) but the days where a CRT would beat a good modern screen in anything are far behind us in my opinion.
Not because it's the cheapest LCD tech, but because it's the most commonly used.
CRTs are rubbish. Use a good quality 4K Q-LED with a decent scaler and you'll get better contrast, better color and no artifacts at basically all resolutions.
I love these types of videos!
As how for how to deal with that oddly mounted board assembly, I would remove the two screws on the bottom plastic one at a time, and insert a nail or undersized bolt into the hole once I remove the screw, in order to support it while still making it easy to remove when I'm ready. Then take off the screw on the side, at which point you pull out the nails while supporting the assembly. This way you're not trying to support it while you're still unscrewing it.
You can get neoprene rubber sheets and cut little square out to fill in those broke screw covers if you dont feel like gluing them in. I've used that stuff to replace covers and rubber feet and it works quite well. You can get it in black and also white, which is nice.
Cap sizling while removing? BAD cap! Don't you dare to resist
8:50
Maybe Louis Rossmann did that board... 😋
At least you got shops that sell capacitors. Our last one in the UK, Maplins what used to be Tandys back in the day, closed down a few months ago :(
What I have done on my 5153 is replace the enclosed power supply entirely with an off-the-shelf industrial 110VDC 100W unit, adjusted up to the required 115VDC @ 800mA.
The reason for this was primarily that I moved my 120VAC 5153 to a 230VAC country, but also because I found the original PS design is cruder than it should be given the year
of design and as-such is quite inefficient. I did find you can remove the aluminum cover without any interference issues which will help it stay cooler.
3:30 where can you buy this masterpiece?
Sounds like someone needs to come up with a crowd funding campaign to manufacture a bunch :D
Woo hoo for paint sticks
He was concerned that a plastic handle wasn't insulating enough, then he uses a wooden stick instead. I'm surprised that he didn't get monumentally zapped, although I think that the metal rod was a shorter path for the current than the wood.
This was designed by an IBM provider: Tatung, no IBM. Great video.
I like the shots that u do
Very nice presentation.
Man, more power to ya. I just don't think I have the nerves or the patience to do that! I'm sure my 5153 needs to be re-capped as well (though it powers up just fine), but I need to figure out why its counterpart, the mighty IBM XT, seems to have a dead CPU or motherboard. No error beeps, no RAM count, nothing.... So many projects, so little time.
Another very important factor when shopping for replacement caps is ESR. Low ESR is especially important in switch mode power supplies.
@sublexxus79 of course. What I meant to say is you need to pay attention to ESR. If the blown cap is low ESR, you will want to replace it with s low ESR cap.
What's your opinion on Fry's Electronics apart from their sub-par capacitor selection?
We had a chain of stores called Maplin in the UK which were very similar to Fry's, but it went bust earlier this year. It was very expensive compared to buying stuff online, but if you needed something quickly, it was convenient. It was also one of the few places were you could buy electronic components over the counter.
Now all we have is Radio Spares, and those stores aren't nearly as common as Maplin was.
I will be doing this soon to some old AT power supplies.
By the way... Would love a video on how to get that old musty basement smell out of new-to-me vintage electronics. :-P
Finally I can see someone using KDE
I took typing classes on a machine like this in the early 90s. I remember the style of the monitor.
Side note: The chassis 5151, 5153, and 5154 CRTs use are actually pretty frail since IBM's plastic formulations tend to age badly...Even screw tightening can cause bits of plastic to break off. I advise any prospective buyers avoid having any of them shipped unless they want a combo monitor/jigsaw puzzle.
Consequently, I also advise not storing them where small/medium objects can potentially land if dropped like I did.
Yup, can confirm, my 5153 has a big chunk taken out of the top, so I'm trying to source a replacement.
GREAT VIDEO...PLEASE MAKE MORE...
Take the crt chassis ground down to groundy ground. You’re at a lower potential than the chassis and that’s why you’re getting zapped. Just clip the chassis to the ground terminal in an outlet before shorting and that should do the trick.
Oh and the “ground strap” going around the monitor I’m pretty sure is the degaussing coil.
Dami Nooki neat, thanks!
I like the part of the first ignition, I already knew that something could explode :D, very good video, I have to do the same and it is a pain in the as..
you can get special HV screw drivers that have plastic running all the way up the shaft to within an inch or two of the tip, that can help.
Brilliant, thank you.
I replaced 8 bulging/blown caps on my dad's old Dell Dimension E521 a couple of years ago....using VERY cheap caps I found on eBay. The system still runs to this day (hell it was running A-OK on the bad ones) but I dread to think what they're like now. I was young and inexperienced on a system that wasn't being used daily at the time, so sue me 😝
I found an IBM 8512 monitor a while back and it is not working. How would I go about troubleshooting it? It has high voltage but no picture of any kind, tried on a known working should-be-compatible card. I'll take it apart when I have the time to see if there are any visibly bad caps or suchlike. Of course there's the possibility that the tube itself is just dead but let's hope for the best.
Nice channel, subbed!
I found out the other day that "copywrite" literally means written advertising/marketing material, they may have actually used that correctly, unintentionally at least.
6:12 It might be accurately described as a component that wasn't designed to be user servicable. They might well have had custom jigs that would make servicing it a whole lot easier.
Maybe this is useful for when you replace the Wan Hung Lo caps by real ones:
If I remember correctly from the time we had an IBM PC at home (yes we did, I have photos to prove it), if you turn the contrast all the way up, the bright text should be as bright as the low-brightness text. During normal use, the contrast knob would be in the center position (with the line on the knob going exactly vertical - just like my OCD likes it), and the non-bright text would be nice and readable while the bright text would be significantly brighter but not blooming or burning your eyes. The brightness knob would be adjusted to the point where the screen wouldn't light up in the black areas.
I believe the 5153 was designed in Japan and made in Taiwan, not a "native" IBM product.
Tatung manufacture.. not horrible.. just a bit "chinesium".. My Tatung crt tv ran 24/7 for 18 years without issue until it just became too dim to watch with the lights on .. then somebody turned it off.. oops.. hahaha.. anybody want it to repair?.. free.. just needs collecting.. even has it's proper remote!!
None of these are native IBM products. The 5151 monitor's design and manufacturing is of much nicer quality than the 5153.
IBM would have released a specification for the 5153 and Tatung would have bid based on their own designs.
If you're going to use a screwdriver, not that I advocate it but have done it many times, you may want to use a screwdriver from Klein with an insulated shaft as they are often used by electricians to screw down live wires - the handles are also rubber insulated. In industrial settings, sometimes there is little option but to work on something live.
These early IBM monitors are just badge engineered Tatung monitors, not actually designed or manufactured by IBM.And the "eerie" lighting is fine, I never really noticed anything was different.
THIS LINE IS BLINKING
Right? I'm glad IBM told us otherwise we'd never have noticed.
I guess it would have been possible -and potentially helpful in the future- to install an un- and repluggable connector instead of soldering the wire back on at 22:55, but yeah, you work with what you have, and also, not every connector would have guaranteed sufficiently reliable connectivity, so you were playing it safe in a way.
I'd get a plastic container, put some isopropyl alcohol in that, put the board in there and scrub it with a soft toothbrush. Should help with the grime nicely.
Also I hope you get a service manual so you can adjust those electron guns properly.
So we have a 5153 with the 5150 computer, and last time we tried running it, smoke started pouring out of the monitor. but the weird thing is, it still worked afterwards (took it out to the garage and rebooted there) And apparently, that wasn't the first time it had happened aswell
My IBM 8512 blew its V-Hold capacitor that sits almost right below the CRT degaussing coil. The thing farted dust and looked like a dried up tootsie roll with the wrapper still on.
Have you tried a VDE screwdriver?
please can you do a clear video of the cables from the cga monitor to the main system of how they are all connnected please, my old ibm is 5160.
I guess I must be somewhat fortunate then; since we don't have anything even vaguely useful like Fry's Electronics, etc anyplace within 100 mils of here, my ONLY option is buying those better components anyway.
As for those covers; perhaps a bit of poster-tack? Something that will hold them in place without actually gluing them in (and therefore readily removable when you need to again).
They way I see it, it might be better to connect the screwdriver to both chassis and earth ground at the same time. That might prevent the shock that the screwdriver gives you, since earth ground has less resistance compared to your body.
Damn, I need a new solder sucker. That one works flawlessly unlike my one.
amzn.to/2D3fjnx (that is an affiliate link and I am obligated to mention it)
I was sick of the terrible ones as well and decided to find one that people actually liked. A "good solder sucker" was starting to feel like an oxymoron. After some looking around though I found people actually had some fondness for this one so I bought it and gave it a shot. It is miles better than any of the other ones I've used! One of the best parts is how easy it is to take apart and clean when it starts to loose the vacuum.
What distro are you using. It looks sooo gorgeous
ua-cam.com/users/AkBKukUabout
Oh i get it, it goes well with your name. Thanks, will try. Btw good luck with that monitor
What's the model of the sludged?
Yes, Arrow still has free overnight shipping, which is really nice. However, don't order blindly as their prices on items can be all over the place.
Nice video, congratulations it is working again! You were lucky !the damage was visible but it often is not the case....just curious what would be your approach if the capacitors looked ok..total recap?seems a bad idea to me.....next time maybe adressbetter the CRT safety stuff verbally because people make so many ignorant comments it pisses me off badly...most people commenting dumb stuff never have been around a crt, they just want to spread misleading information like earthing the whole thing , they even talk about x-ray danger on B&W 10kv CRts on other videos.
The wooden improvised tool was overkill you can stick a screwdriver inside the cap and touch it to the aquadag and its enough.be sure to use a isolated screwdriver and not the ones with the exposed metal end, you know, the ones that you can hit with the hammer to work like a chisel. you can also use a screwdriver with a clip lead to chassis for extra safety.
Using flux to Solder the capacitor and using solder sucker was also overkill, maybe you explained why but i watched the video with muted audio..anyway through-hole components, if the board is clean and the component legs are corrosion-free everybody uses just fux-core wire , i know everybody wil be bashing this comment but they dont do electronics work...to unsolder a 2 leg component wich will go to the trash its easier to touch the iron to one leg, pry the component to one side, then touch the other leg and pry the other way around or simply add fresh solder, put the iron sideways to touch both legs and pull the component. sometimes the solder sucker doesnt suck completely and you can damage a trace by pulling the component (not a big deal here but...)
I think like you've seen here, explaining how to discharge a CRT is meant with skepticism unless you're wearing a full rubber suit with a Faraday wrapped around it connected to "earth" ground. One of my favourite remarks I've seen is "Also, don't think a CRT which has been powered off for a long period of time will be safe - the CRT will slowly continue to build static electricity just due to the Earth's rotation and magnetic fields." So for the most part I'm going to tell people enough that they should at least be alert about it, but I don't want to try and fight the endless wave of ignorance.
I've found soldering for personal/professional use and for video are two different things. Normally, flux in the situation would absolutely be overkill. But when you can see everything in this kind of detail everyone gets hyper-critical about the smallest mistakes. So a slightly frosty soldered pad or a non-perfect looking joint will get tons of comments complaining I suck at soldering. So I find it's better to just make it picturesque so people just chill out. I use that "wiggle" method to remove SMD caps all the time, it is fine. In the 15-30s of soldering I'll show in a videos like this it gets tiresome to explain every step every time.
For the record, I use Kester 63/37. So I am using a rosin core.
The screw drivers I have all lead to me getting zapped. Like you said elsewhere, it's not actually that bad since the CRT stores so little total energy. I used the paint stick mostly for comedic effect here. I'm going to see about making a proper tool for this out of something like a coat hanger and a wooden dowel.
And on troubleshooting:
Since I had been experiencing problems with the red and blue channels independently changing intensity I knew the fault would be somewhere that had discrete analog control over them. So I would have looked for parts of the board with the same circuit repeated three times. Anywhere that had a big cap in those circuits I would have removed the cap and tested it with my ESR meter until I found one out of spec.
Or once I have some cash to burn on tools, get a flir and just find the hottest cap on the board. It's probably that one.
i agree with your first reply...its the same on videos were people use an angle grinder or power tools...people are not familiar with the subject and are hyper sensitive/aggressive about safety...
i now understand why you wanted to make a perfect job on camera, thus the use of flux, solder sucker, etc...i also expected negative replies to my comment because everybody seems to love flux nowadays...for through-hole or point to point i just dont use it..smd is other story...
about the screwdrivers i draw sparks all the time out of the anode caps of Horizontal output valves on vintage tv's (i like to repair them) and i dont get zapped that way, i just make sure to grab the screwdriver not too close to the metal part of it (hope it makes sense)...high voltage will try to arc to the nearest ground potential point so make sure that point is not your body...sparks will arc maybe one centimeter not more so if you keep that distance from the metalllic part of the screwdriver you will be safe...but you do whatever you feel more confortable, if i got zapped using a screwdriver i would not want to use it either :)
about the troubleshooting , there should be three equal transistors that amplify red green and blue signals, they would be also suspects....most of the times you can test for ESR in circuit even if there is a resistor or diode in parallel..its not accurate but you can..saves a lot of trouble... capacitance reading has to be done out of circuit 90% of the times because any dc path around the cap will badly mess the reading...
thank you for taking time to read comments, nobody seems to do that! i really appreciate it!!!
keep the good work
I have seen a cap in a DC lab power supply go off like a tiny grenade leaving paper pulp all over the inside of the case. the can hit the top of the case so hard it was flattened at an angle.
He heard it blow. You heard it here. I'm a UA-cam news reporter for VSauce.
At least it was a color monitor. When a green phosphor monitor turns pink you’re screwed. You couldn’t possibly run fast enough
I would love to see you try GEM (wikipedia.org/wiki/Graphics_Environment_Manager) on your 5150. I could not get GEM 1.2 (from: winworldpc.com/product/gem/1x) to run on my 5150 (it hangs itself after loading the desktop) with 256kb Ram, but it may work with 640Kb.
I just realized that you have the same screwdriver I have LOL
I was terrified for your safety this entire video. Sheesh.
29:19 How about some blu-tack? Sticky but removable/reusable.
I love a nice old crt, but I hate working on them.
Should have made yourself some kind of quick disconnect for those few wires you had to desolder/resolder to the tube side. Would have made the next time you take it apart slightly less painful.
Im dreading the day I have to recap my Kaypro
Oil filled caps ftw :-)
4:20 "Shockingly filthy" I rebuild a 5154 that looked like it had been in a basement flood, boards were caked in mud. At least I hope it was mud...
Its opposite day isn't it?
Jackcon capacitors aren't that bad, but it was a really bad idea to replace capacitors in only 2 out of 3 color channels. I have never seen capacitors packed 1pcs each in a separate blister ;) in my local electronics shop they have them in drawers, eventually on reels, and they put ones you want in a plastic bags.
a wooden plank you really go overboard xD
Use some blu-tack instead of hot glue to make the covers easily removable.
Even better glue on the underside focusing magnets from a discarded CD drive.
Just curious, what microphone do you use?
I use a Marantz MPM-2000U for voice work.
Dunno if you alrrady have one but i just printed a sweet fume extractor from thingiverse. I cant believe i let myself huff flux smoke this long
"simple" ... 31:42 ... yup, this is an akbkuku video, best get the popcorn
Any advice on connecting a Pi to a old 80's monochrome display? I want to run it inside a IBM 5150 case and give the illusion of a DOS machine but run command line Linux. There is the monitor Im dealing with: ps-2.kev009.com/pcpartnerinfo/ctstips/5546.htm
Next up.. replacing the same value cap on the green gun.... or one of those crap Jackcon ones.. also.. that nasty green one by the frame output stage will go pop sooner or later (stock Tatung fault)
It isn't IBM that made those printboards. It's Tatung. It's clearly branded. Tatung still made cheap LCD tv's in 2005, I bought 4 of them at that time. They still produce cheap LCD-tv''s in their factory in Czech Republic for the european market.
"It's shockingly filthy" lol
If you don't get zapped while discharging it, how do you know that it's really discharged? :p
But wait! You got shocked by grounding a CRT?!?! HOW ARE NOT DEAD!?! I mean EVERYONE on the Internet says CRT's KILL!!! The way people carry on about these things, just taking the cover off means INSTANT DEATH!! OMG MAN you are so lucky too be alive!!! :rolleyes:
I can answer that - it all depends on where you get shocked - if the anode and cathode touch the same part / area of your body (say you're right handed and the anode and cathode both touch part of your right arm - you'll get shocked (obviously) but not necessarily life threatening - it is when you say use BOTH hands and the current has the chance to travel across your heart - that's when you're in a load of trouble
When discharging CRTs, wear some good gloves, like in the 8 bit guy videos.
or just take the shock and cry like a baby afterwards lol
Letter Slayer You won’t be crying afterwards.
@@TrolleyMC ok, maybe i exaggerated a little...
26:57 *Line intensifies*
Its extremely weird that you would get zapped. First nearly all crts have a bleeder that discharges the system pretty quickly after turning it off and second as long as your connection between the chassis, wire and screwdriver are even remotely sound you should be completely safe. Ive done that procedure with dozens of crts and have never felt a thing. Were you touching the chassis maybe?
Well if his chassis was not grounded and that clearly uninsulated screwdriver conducts even a little.. a shock is to be expected. An insulated screwdriver with a grounded chassis should be perfectly fine.
Not many people catch the moment when caps explode in a monitor.
ＴＡＴＵＮＧ！
hmm sounds like those jackcon caps need to be abused when you replace them
plug um into a 240v appliance plug on high speed potato vision and make sure to use a fuse or your breaker will get a workout
In the uk just plug in the power cord with the plug switch off then ground it through the case it will then goto ground via the power cord.
I have seen many a house wiring in the UK where the earth does not go any further than the back of the plug socket.
@@TheDutyPaid then who ever wired them houses shouldent of been hired when in doubt conect an earth wire to a bare bit of copper on a radiator just make sure no body touches it at the same time as u discharge :-)
You still see lighting circuits without earth. Mains side is quite rare but as any one is free to do as they like, then a working earth is often overlooked.
I have no radiators in my house but the earth runs to an earth post where the mains comes in and a secondary to the mains water pipe.
You dont need to be a genius to see whats wrong with that.
@@TrolleyMC what is wrong with what?