It's perfectly safe as long as you don't poke around under the anode cup... UNLESS you forgot to connect that ground cable he warns about. Inside of the tube gets charged to a high voltage. Outside is supposed to be grounded. If it's not, the high voltage has to go somewhere. You don't make that mistake twice.
Same here, but myself I've worked on a live color CRT (which runs off a higher anode voltage, something close to 24-25kV (kilovolts and not *kill*-o-volts)). It was the most unnerving 30 minutes of my life. Now, I'm gonna be going on a limb from now on in this post, what imma say might not be 100% exact, so take this with a grain of salt..! So as long you know what you're doing and don't stick your fingers where you should not (anode cape for instance....) you should be fine. (so as long the tube is also properly grounded). Also there's a even bigger danger, the large capacitors in the power supply section, those fat caps can hold a charge that probably has more "Oomph!" than the CRT itself.
There is a method for rejuvinating the CRT: You will need few hundred volts and low current (through some resistor) between the cathode and the grids and with everything connected you put twice the voltage on the heater fillament for 20 seconds. You repeat this process few times. This clears the cathode coating exposing new surface which brings the brightness back to original for some time.
We had a test box that was used for that. It was hit and miss but if you have a dim crt what do you have to loose. Prob around on ebay or junk ships. it was a "CRT rejuvenator"
I watched a video a while back about refurbishing old CRTs. It was from a guy who ran a CRT repair shop. He was replacing the electron guns on the tubes, and as part of the vacuum process, he put a coil around the getters and pumped high-voltage and high-frequency RF through them, which made them glow super bright. This caused any oxygen and other gasses left in the tubes to react with the getters, removing any last molecules of gas left in the tubes. Or something to that effect anyway. Without this step, the tubes will be dim, and eventually fail as the electron gun would be oxidised over time. Or worse, the phosphor coating on the front of the tube could be oxidised, which is basically that phosphor rot you see on bad tubes, and is pretty much the end of the line for the tube.
@@iroll I agree. Both channels rock and very informative. Twinkle-tworbulate, silver mica disease, crusty, here, here and heeere. Hahaha! You can tell I've been to Shango world too long.
vinegar bath to neutralize the rust, wire brush and wirewheel to remove the loose rust, gray weldthru primer to cover and protect the exposed metal from further damage.
Adrain thank you for still making videos!! Please don’t stop. With all this nonsense/anger/frustration/uncertainty...watching your videos reminds me of when I used to watch them at work. “Job currently furloughed”...but it makes me smile and makes me temporarily forget. NO PRESSURE...I’m sure that’s weird to hear but very truthful! Stay safe and don’t believe what you hear!! And That’s to everyone who reads this..make your own mind up don’t let media and social media do that... maybe one day things will be ok... Adrian your thoughts?
Nice video again! As you deal quite often with CRTs in these old systems, and that they're no longer made as you say, I would say it may be worth your while investing in a CRT rejuvenator. They still come up for sale every now and again, I have a B+K one i've had for years that I use with arcade CRTs sometimes (you see them on eBay sometimes although I can't remember where I got mine from). Very occasionally you'll get a CRT that doesn't last that long (as far as brightness/contrast goes) after trying it but most of the time you can get quite a bit more use from a CRT once it's been given a rejuvenation.
When a Xerox Alto was being restored (by CuriousMarc et al) its CRT was very dim at first too. But after hours (days?) of being on, its brightness was restored.
I suspect that you could probably clean off most of the rust with evaporust or just plain old vinegar. Shot blasting might be a better bet if you have access to a shot blaster.
@@AndyHullMcPenguin As someone who winces every time something is thrown away, I kept thinking Adrian should mail the piece to some of these youtubers that restore rust-ladden electronics, like Odd Tinkering. I'm sure they'd do a decent job on that.
I learnt not to touch CRTs since I was first shocked by a small motherboard with a small amount of AC going through the ground while I was touching it, I couldn't imagine how touching a CRT would feel like. I'm seriously impressed about how safe Adrian is to touch the back of the CRT to correct the image rotation like that, pretty darn cool.
Adrian : Now that we've got the major issues on this Mac fixed let's check out what's causing brightness on this Mac. Mac: Checkmate, Adrian! Your move! 🤣
Great video as always. I do feel bad for #5, but he sacrificed himself for the greater good. Still I can't get the this quote from the movie Short Circuit out of my head now: "No dissemble Number 5." lol
I had a one gig full height scsi drive on a sun sparc center 2000 that would only work if you warmed up first. A hair dryer did the trick. After it started it worked fine.
These older hard drives also are prone to stiction, where a lubricant/chemical layer that's coated on top of the Mylar platter, degrades and accumulates between the disc platter and read/write head, acting like glue. You can cure this temporarily, enough time to recover and backup data, by holding the drive in your hand. With a horizontal flick of the wrist, very quickly do a half-turn of the drive a couple times until it becomes free moving. The stiction sometimes prvents a drive from spinning up and initializing before boot.
Have you ever tried a crt rejuvenator on one of these? Many years ago i tried a crt rejuvenation machine on my then 70’s woodgrain TV and it did brighten up the crt. The halftones were still pretty crap but overall brightness was definitely improved.
I'm thinking you should invest in a sand blower to remove the rust and paint off of the metal for repainting, help with your restoration projects look even more amazing! ^.^
Yeah, the only way to save that rusty metal frame would've been to use an angle grinder with a wire wheel or a sand blaster to get rid of all the rust, then prime and paint it to seal the bare metal. Way too much work just for a frame from a Classic. Especially if you're taking parts out to fix other machines, not to mention the corroded logic board! Might've been worth saving if it were an SE/30 or some other rarer model, but not for a Classic. My capacitor order has arrived, so I can recap my SE/30 board, but it's almost midday on Sunday already so I don't know if I'll have time to get the recap done this weekend. But it still blows my mind how tiny these SMD 47uF ceramic caps are! Anyway, good to see progress on the repairs, can't wait for the next episode!
I was thinking the same. Plenty of solutions: manual sanding, sandblasting, a power tool with wire brushes, even an angular grinder, or evaporust, electrolysis...
Especially not in the trash bin. At least throw it in your recycling box/bin if you're going to throw it away. Its recyclable steel. Don't just put it in the landfill bin
@@simontay4851 Heck, he should give it to someone else rather than just chuck it. Someone can use it and someone is surely willing to put the work in to clean it up.
Fumes from that battery could also rise up and corrode the metal above it. You can also try a CRT rejuvenation unit on that CRT and possibly bring it back to brightness.
If you needed to reuse that rusty chassis, buy some EvapoRust (1 gallon might work). Dunk the rusted portion into a container that can hold the EvapoRust liquid over the rusted area and leave it overnight. The next day you’ll find all of the rusty areas are a dark gray that indicates the rust has been completely removed. After a good rinse and scrubbing with a toothbrush it’ll look much better except for the pitting. Next, use some spray paint like a zinc-based one to protect the naked metal and you should be good to go. I keep a five gallon of the EvapoRust in my workshop just for situations like this. Amazing stuff.
Not sure if you have the space for it, but a mirror on the back of your work area makes working on CRTs a lot easier and safer. You can put it at a slight angle to see over the top. Trick I remember from my work experience days (Probably about 35 years ago now).
I bought a SE/30 on eBay with a similar or even worse battery spraying. The chips on the logic board are completely gone and the metal cage is heavily corroded. Fortunately the plastic case is in perfect condition. I hope I will find a working logic board soon.
Yeah, sometimes if the hard drive doesn't reach a specific speed within a certain time frame, the hard drive will power off. Some machine oil on the spindle bearings, if you can get to them, will help. Just one or two drops and let it sit overnight usually works quite well. Or if you can't get to the bearings, what I like to do, is run the hard drive upside down for a time. Sometimes the old grease will liquefy and move to the other side of the bearings and re-lubricate them.
I'd love to give a CRT rejuvenator a shot on one of these tired tubes. I don't have any classic (as this) Macs of my own, though. Hoping to change that some day. Got a Heathkit rejuvenator which worked to restore a 1974 RCA color TV with a dead red gun - now it works bright and clean as new (in 2020 with all original parts!). It might have a dongle compatible with this Mac tube...
That battery probably reverse-charged in some of the cells and got too hot and vented like a bad electrolytic cap. I’m surprised it didn’t catch fire. 😬
It's a single cell 3V lithium primary battery, so no multiple cells and no charge. Simply the seals deteriorate over time, and they leak. The rust above the battery might be caused by the fumes of the electrolyte.
My humble opinion. Take the chasis to a mechanic/body shop and ask them to run it through their sand blaster, then you can treat it with anything to keep future corrosion down, and BAM, ya saved it!
My Mac was upgraded with 2 4MB SIMM modules from memoryx dot com for about $12 total. Also installed the SCSI2SD adapter since the SCSI drive was so dang loud.
FYI, you can rehab the rusty chassis by letting it sit in Apple Cider Vinegar overnight. I did this with my Mac SE/30 and it worked great.I ended up using apple cider vinegar and Barkeep's Friend to remove all the rust. Then I sprayed the chassis with primer. Looks great now!
On HDD #5 you can open it and unstick the back of the arm. As the bumper material degraded over 30 years it gets sticky and prevents the arm from moving properly. I've had more than a few suddenly spring back to life by carefully pulling the arm off the platter. You can't really trust the drive after that but it's a useful trick to create a narrow window of opportunity to pull data off of it. That said, sometimes it just won't work at all.
I would suggest after taking a wire brush to the rusty chasse to then use some of the chemical rust converter like rustex (rust is chemically changed to iron phosphate) which then protects the rest of the metal, then a quick spray with some metal primer and you're good to go.
i totally recognized you Tandy board in the last LGR Video... Adrian (@Adrian's Digital Basement) at minute 9:31 .. >> ruclips.net/video/FmmN9k7v2_8/видео.html
I can't wait until OLEDs mature to the point where they start making panels that are curved to match picture tubes of the same size. Then people can start repurposing screen housings for even more authentic-looking projects.
@@stevethepocket that will be exciting, although it may be microLED rather than OLED by then (the maturity on curvature for arbitrary CRT curvature, and the panel longevity/burn in reduction - bearing in mind all but Trinitrons are curved in two directions not just one like folding phones)
My messages said 3 days ago, but this says 3 years ago. Anyway, it was still great as I just did a CRT replacement myself on my Classic II just tonight, so thanks
High turning up the brightness may not improve anything because most CRT monitors have a beam limit circuit, so if you increase the brightness it will probably back off the contrast or brightness or both depending on how they implemented it. If you have a really tired CRT you can try to rejuvenate the CRT, I have had some good results with monochrome CRT's.
It’s such a relief to watch Mac repair without terrible puns, histrionic behavior, constant forced laughter or weird “skits”. Sadly, we have to scroll so far to get here past Mac84, CuhRAAAZY Ken, RetroRecipe and HRUTKAY.
Back in the day i was using scsi... it was fast but loud and they were heaters especially those 15k seagate cheeta drives... 2 15k raided drives had some unbelievable speed.
That rusty chassis is completely salvageable. There are so many easy ways to get rid of rust. You could simply sand or wire wheel it. There are countless rust remover liquids and gels. You could sandblast it. Sonic cleaners work great too. It just seems off for someone who wants to preserve these old computers to just toss away a perfectly usable part.
Good Ole stiction... A lot of my older macs did this if they sat too long. especially with the connor drives... my guess is age isn't kind to the lubricant in the motors, and while you can get them going again, sometimes the drive will stick again at some point.
Keep up the good work... I hope to resurect my Classic II when I change the caps... The re-cap kit should be in the on the way.. (I dishwashed the MB and two of the caps actually fell of.)
The hard drive on my IBM 486 does that thing too. If it hasn't been started for a while you have to give it a tap to wake it up. I have heard it called 'sticktion' like stick and friction. Is that a real term? I don't know :-) It's like the bearings are dry. I wonder if they can be lubricated.....mmmm, interesting. Great series. Cheers
Two things. You could easily use rust stop or alternatively sand it off and spray anti corrosion paint. Finally if you must throw away recycle the metal
These small monochrome CRTs need a TON of hours to go that dim. I've recently bought two 8" monochrome CCTV monitors that was installed in some industrial control system, they were on 24/7 for many years (probably 10+ years), both has horrible burn-in marks on the screen, but they are still as bright as an atomic blast! And those are not Samsung, but Chungwha. Your CRT might have cathode poisoning, the cause can be the low supply voltage: if you run vacuum tube filaments undervoltage for a long time, you can get cathode poisoning. Don't throw out that CRT, it probably just needs a light rejuventation, I don't think the emissive coating on the cathode got used up, just its surface is deteriorated, which can be cleaned off gently with the right rejuvenator.
Rejuvenation is not a permanent solution, since the tube will get dim again after some time. As youtuber Shango066 once said: "Rejuvenation was just enough to get the customer to shut up until you could order a crt or get him into a new TV". What your saying about cathode poisoning could be somewhat true, but really, wearing out a picture tube doesn't take a lot. Just use it with the brightness set too high and you'll get a dim picture in less that 10 years. The crts you have were probably run with low brightness and that's what saved them.
@@enzoperruccio I'm not a fan of rejuvenation either, and you're right, it is *usually* just a temporary fix - if the CRT is tired, so the emissive coating is worn off, it won't do wonders. BUT it can permanently repair cathode poisoned tubes, unless the poisoning was due to gassiness. It also can permanently repair some tubes with high hours in it, but which has very thick emissive coating on the cathodes, and during its lifetime as the material evaporates, it's getting deposited between the cathode and the G1 element, causing a partial or full short. I've seen rejuvenated CRTs working for 3-5 more years with good picture after rejuventaion. I personally don't have a proper rejuvenator, but even the crude method of applying rectified 230V through a 60W light bulb between the cathode and G1 worked great for me on certain tubes. It kills about half of the tubes, but some will last years even after this crude method (a genuine rejuvenator would give much more consistent results). After all, the reason why I think this would work with this Mac CRT, is the fact that it has no screen burn. Computers used in industrial/office environment usually show static images, or at least portions of the image is static, so the screen usually develops some burns over its lifetime. That's why I thinking it's not an overused, very high hour CRT, so it can be a good candidate for rejuvenation.
I would still replace any electrolytic capacitor I found in any of these systems (analog board or mainboard). These computers were hotboxes from day one, and have just seen too many hours at this point. A modern tiny quiet fan strategically placed near a vent hole couldn't hurt them moving forward either.
I worked in a wafer fab for a few years. We have had an spray etching machine wich used hydrochloric acid. Behind this machine was a wall and on the other side of this wall was a PC. The pure vapur of the acid was engough that this PC must be changed every two years. They where completly corroded after that time. So I think the vapur of the battry acid did this corrsion.
One thing you can try on the Classic motherboards is booting from the ROM Disk. Just hold down Command-Option-X-O until the system starts to load and you'll be running System 6.0.3 from the ROM. Sadly, it doesn't work on the Classic II motherboard. Also, make sure not to hold the keys all the way to the desktop, otherwise it'll try to rebuild the desktop file, which won't work for fairly obvious reasons.
To be more clear you are adjusting the black level or brightness for the dim setting you are doing and contrast white level for the max setting really.
It's actually not good to adjust the voltage if you suspect that the power supply is faulty because if that solder joint connects by itself you will have bad overvoltage.
Dim CRT has nothing to do with caps unless B+ is low because one is shorted out or failed open. Low emissions from the electron GUN is more likely due to high hours and electrode vaporization. Check B+ is in spec, check pots for values out of spec. Check voltages on the neck board too. Should be specs out there.
Hi from Aust!. You said that other tube was worn out? Its guns could just need a clean/rejuv. Do you have a CRT Restorer Analyzer? I saved many tubes and they are great if you have old video arcades machines you still run or people need you to restore theirs sometimes. Great channel and look forward to each riveting instalment of a fix you take on.
11:20 - actually in the "old days" replacing the tube was a last resort - quicker & cheaper to use a tube rejuvenator... As long as thee is no screen burn it's worth rejuvenating a tired CRT.
The battery wouldn't have sprayed, it's more likely it was from gases emitted from the electrolyte as it evaporated inside the case (along with electrolyte from the caps reacting with it probably), I don't know what gases they would be from a battery as I'm no battery chemistry expert, but chlorine and similar can cause rust like that without contact, such as hydrochloric acid evaporating near steel, that makes things rust fast...
yo! I’m having a strange issue with my 1998 iMac G3. It works without any problems initially, but when it’s left on for a long time, a weird bug occurs that’s difficult to pinpoint. After being on for an extended period, my iMac G3 simply goes into a black screen mode if there’s any change in video resolution. Additionally, when I turn it off and try to turn it back on, the power LED stays green, never turning off, and the machine doesn’t power back on. The same happens during a reboot; instead of the LED turning yellow and then green, it doesn’t return from the reboot. Even with the startup chime playing, the screen remains black. The only solution is to unplug it and plug it back in. After being unplugged for a while, it returns to normal, but the bug reappears if it’s left on for several hours, typically two or more. I’m not sure if this is an issue with the mainboard, power supply, or analog board. I’ve already recapped 100% of the capacitors, and while the bug used to be permanent, it’s now intermittent. At first, I thought the recap had solved the problem since I only used the iMac for a short time, but when I use it for longer periods, the bug always comes back. It only stabilizes if it’s unplugged for at least 10 hours. Any attempt to turn it back on after the bug appears is futile. Do you recommend checking any specific chip or shutdown signal? Thanks for the help. Oh, I forgot to mention, only the electrolytic capacitors were replaced during the recap.
You could have wire brushed the steel frame and sprayed some Hot Cat Piss (Phosphoric Acid) to neutralized the rust on the metal and spray it on the rest if the frame to protect it. After buffing it with some steel wool, spray it with some Rustolium Chrome paint and buff it to restore it. Go find the Larry Pina Mac Classic Secrets And Upgrades book. It in .pdf online somewhere. It will tell you the exact specs for the screen image and some basic repairs you are missing.
Are You able to rejuvenate that tube? Shango066 shows on his channel how to use Beltron/Super Mack CRT testers which have also a rejuvenation function.
If you watched his videos you'll also know it's only a temporary solution, meaning the tube will get dim again after some time (could be hours, days or even weeks, but it will get dim).
Hi Adrian. What’s the status of that corroded board you sprayed with WD-40? Has it caused any additional corrosion, or damage to plastic bits? Are the traces and pads still shiny? And how did you get the WD-40 off?
HI Adrian, nice fix.. just wondering, on the CRT image it seems a bit small, roughly 1/2" of black around the edges... is the yoke pushed fully forward? That can sometimes cause that as you may know. Other than that maybe screen height and width are set low... the HV seems fine so that cannot be the issue. Not a huge MAC fan, but a good fix video non-the-less. It's funny how the CRT stuck around the longest as the specialized vacuum tube, it's siblings are the magic eye tubes (eg. 6E5) and it's "blind" predecessors (diodes, triodes, (kinkless) tetrodes and petagrids)... the CRT evolving out of the electrostatic deflection with the adaptation of external(!) magnetic windings. Fascinating stuff. (Bonus question, looking back do you ever wonder how someone could do daily work on a CRT screen that small? Seems tiny compared to the LCD panels we have now. Still, nothing beats FPS on a large CRT.) Cheers, hope you are staying safe now.
When the yoke isn't in the right position the corners of image get cut off ... the size is simply an adjustment on the back of the machine. And yeah the tube is just a vacuum that stuck around in the 2000s. Funny really! As for small CRTs-- it's not that much of an issue when you are only running one program at a time. But similarly I can get actual work done on my 6" phone if I need to. :-)
Just out of curiosity, is the rusted chassis and the plastic housing for sale? I've been looking for a Macintosh to build a PC inside of, but I didn't want to decommission a working one or a good-condition chassis that could be used to repair one.
just a question. Could you still salvage those parts? Being that there aren't many of those computers around? the rust. if not too bad could be ground out of the metal right?
IIRC, SCSI hard drives will go through their startup and if they don't see a bus signal, will spin back down... but then that doesn't explain the further spin up-stay up afterwards...
Going near a CRT tube when it's on always gives me the heebies!
It's perfectly safe as long as you don't poke around under the anode cup... UNLESS you forgot to connect that ground cable he warns about. Inside of the tube gets charged to a high voltage. Outside is supposed to be grounded. If it's not, the high voltage has to go somewhere. You don't make that mistake twice.
Same here, but myself I've worked on a live color CRT (which runs off a higher anode voltage, something close to 24-25kV (kilovolts and not *kill*-o-volts)). It was the most unnerving 30 minutes of my life.
Now, I'm gonna be going on a limb from now on in this post, what imma say might not be 100% exact, so take this with a grain of salt..!
So as long you know what you're doing and don't stick your fingers where you should not (anode cape for instance....) you should be fine. (so as long the tube is also properly grounded).
Also there's a even bigger danger, the large capacitors in the power supply section, those fat caps can hold a charge that probably has more "Oomph!" than the CRT itself.
Gives you bigger heebies when you touch the voltage
This is a really great Repairathon; also enjoying the Mail Calls. Thanks so much for all this content.
There is a method for rejuvinating the CRT: You will need few hundred volts and low current (through some resistor) between the cathode and the grids and with everything connected you put twice the voltage on the heater fillament for 20 seconds. You repeat this process few times. This clears the cathode coating exposing new surface which brings the brightness back to original for some time.
We had a test box that was used for that. It was hit and miss but if you have a dim crt what do you have to loose. Prob around on ebay or junk ships. it was a "CRT rejuvenator"
I watched a video a while back about refurbishing old CRTs. It was from a guy who ran a CRT repair shop. He was replacing the electron guns on the tubes, and as part of the vacuum process, he put a coil around the getters and pumped high-voltage and high-frequency RF through them, which made them glow super bright. This caused any oxygen and other gasses left in the tubes to react with the getters, removing any last molecules of gas left in the tubes. Or something to that effect anyway. Without this step, the tubes will be dim, and eventually fail as the electron gun would be oxidised over time. Or worse, the phosphor coating on the front of the tube could be oxidised, which is basically that phosphor rot you see on bad tubes, and is pretty much the end of the line for the tube.
Adrian should try this and make one or two video about the "CRT rejuvenator"
@UpLateGeek Shoutouts to Shango066 and bandersentv
@@iroll I agree. Both channels rock and very informative. Twinkle-tworbulate, silver mica disease, crusty, here, here and heeere. Hahaha! You can tell I've been to Shango world too long.
vinegar bath to neutralize the rust, wire brush and wirewheel to remove the loose rust, gray weldthru primer to cover and protect the exposed metal from further damage.
Adrain thank you for still making videos!! Please don’t stop. With all this nonsense/anger/frustration/uncertainty...watching your videos reminds me of when I used to watch them at work. “Job currently furloughed”...but it makes me smile and makes me temporarily forget. NO PRESSURE...I’m sure that’s weird to hear but very truthful! Stay safe and don’t believe what you hear!! And That’s to everyone who reads this..make your own mind up don’t let media and social media do that... maybe one day things will be ok...
Adrian your thoughts?
Nice video again! As you deal quite often with CRTs in these old systems, and that they're no longer made as you say, I would say it may be worth your while investing in a CRT rejuvenator. They still come up for sale every now and again, I have a B+K one i've had for years that I use with arcade CRTs sometimes (you see them on eBay sometimes although I can't remember where I got mine from). Very occasionally you'll get a CRT that doesn't last that long (as far as brightness/contrast goes) after trying it but most of the time you can get quite a bit more use from a CRT once it's been given a rejuvenation.
Certainly learning a lot about the mysterious Mac, Adrian! Thoroughly enjoying this series so far!! 👍
Many years ago I remember playing games on a Mac like those... Neat to see them getting fixed.
When a Xerox Alto was being restored (by CuriousMarc et al) its CRT was very dim at first too. But after hours (days?) of being on, its brightness was restored.
The vapor when the battery acid evaporates may be corossive too, at leastbenough to cause surface rust!
Was just about to comment this😂
I suspect that you could probably clean off most of the rust with evaporust or just plain old vinegar. Shot blasting might be a better bet if you have access to a shot blaster.
@@AndyHullMcPenguin As someone who winces every time something is thrown away, I kept thinking Adrian should mail the piece to some of these youtubers that restore rust-ladden electronics, like Odd Tinkering. I'm sure they'd do a decent job on that.
Yep, I had a cup of Muriatic Acid on my bench and it rush the crap out of everything in the area that was exposed iron.
NASA preflight for the launch in the background and Adrian working on Mac Classics. What a great Saturday morning/afternoon. ;-)
I learnt not to touch CRTs since I was first shocked by a small motherboard with a small amount of AC going through the ground while I was touching it, I couldn't imagine how touching a CRT would feel like. I'm seriously impressed about how safe Adrian is to touch the back of the CRT to correct the image rotation like that, pretty darn cool.
Every time a vintage Mac gets save an Angel gets his wings.
Love the expression on Adrian's face at 11:35 when he discovers the hidden chess mode on his Mac 🤣
Was just thinking that! I love that look of utter confusion on his face😅
Great that he included that in the video, rather than edit it out.
I actually thought it was a bit staged. I wonder if he found it off camera and later reenacted it.
Adrian : Now that we've got the major issues on this Mac fixed let's check out what's causing brightness on this Mac.
Mac: Checkmate, Adrian! Your move! 🤣
Poor number 5. It gave it's life so that others may live! Enjoying this series Adrian, looking forward to the next one.
I'm so hooked on this series. Can't wait for the next one.
Great video as always. I do feel bad for #5, but he sacrificed himself for the greater good. Still I can't get the this quote from the movie Short Circuit out of my head now: "No dissemble Number 5." lol
Sometimes the HDD bearings are fluid bearings and they get sticky, warming them up helps temporarily.
Good tip! I’ll keep it in mind if I get a Macintosh
I had a one gig full height scsi drive on a sun sparc center 2000 that would only work if you warmed up first. A hair dryer did the trick. After it started it worked fine.
@@Codeaholic1 so just do that every day and your good. Lol
These older hard drives also are prone to stiction, where a lubricant/chemical layer that's coated on top of the Mylar platter, degrades and accumulates between the disc platter and read/write head, acting like glue. You can cure this temporarily, enough time to recover and backup data, by holding the drive in your hand. With a horizontal flick of the wrist, very quickly do a half-turn of the drive a couple times until it becomes free moving. The stiction sometimes prvents a drive from spinning up and initializing before boot.
@@blackterminal haha. I did it long enough to migrate the data off.
Have you ever tried a crt rejuvenator on one of these? Many years ago i tried a crt rejuvenation machine on my then 70’s woodgrain TV and it did brighten up the crt. The halftones were still pretty crap but overall brightness was definitely improved.
I'm thinking you should invest in a sand blower to remove the rust and paint off of the metal for repainting, help with your restoration projects look even more amazing! ^.^
Yeah, the only way to save that rusty metal frame would've been to use an angle grinder with a wire wheel or a sand blaster to get rid of all the rust, then prime and paint it to seal the bare metal. Way too much work just for a frame from a Classic. Especially if you're taking parts out to fix other machines, not to mention the corroded logic board! Might've been worth saving if it were an SE/30 or some other rarer model, but not for a Classic.
My capacitor order has arrived, so I can recap my SE/30 board, but it's almost midday on Sunday already so I don't know if I'll have time to get the recap done this weekend. But it still blows my mind how tiny these SMD 47uF ceramic caps are!
Anyway, good to see progress on the repairs, can't wait for the next episode!
That rust can be sanded away and repainted with anti corrosion paint.
Or maybe using Evaporust and then a spray painting.
I was thinking the same.
Plenty of solutions: manual sanding, sandblasting, a power tool with wire brushes, even an angular grinder, or evaporust, electrolysis...
Yes, the chassis shouldn't just be thrown away.
Especially not in the trash bin. At least throw it in your recycling box/bin if you're going to throw it away. Its recyclable steel. Don't just put it in the landfill bin
@@simontay4851 Heck, he should give it to someone else rather than just chuck it. Someone can use it and someone is surely willing to put the work in to clean it up.
You're managing to get a few good ones here.
Thanks for taking us on this journey.
Conner hard drives brings back some memories
I'm realy enjoying this series, I've only used a Mac like these once, and that was only for about an hour at a friends.
I’m really enjoying this series!! Hoping that you can get the rest working!
Fumes from that battery could also rise up and corrode the metal above it. You can also try a CRT rejuvenation unit on that CRT and possibly bring it back to brightness.
If you needed to reuse that rusty chassis, buy some EvapoRust (1 gallon might work). Dunk the rusted portion into a container that can hold the EvapoRust liquid over the rusted area and leave it overnight. The next day you’ll find all of the rusty areas are a dark gray that indicates the rust has been completely removed. After a good rinse and scrubbing with a toothbrush it’ll look much better except for the pitting. Next, use some spray paint like a zinc-based one to protect the naked metal and you should be good to go. I keep a five gallon of the EvapoRust in my workshop just for situations like this. Amazing stuff.
Not sure if you have the space for it, but a mirror on the back of your work area makes working on CRTs a lot easier and safer. You can put it at a slight angle to see over the top. Trick I remember from my work experience days (Probably about 35 years ago now).
I bought a SE/30 on eBay with a similar or even worse battery spraying. The chips on the logic board are completely gone and the metal cage is heavily corroded. Fortunately the plastic case is in perfect condition. I hope I will find a working logic board soon.
Yeah, sometimes if the hard drive doesn't reach a specific speed within a certain time frame, the hard drive will power off. Some machine oil on the spindle bearings, if you can get to them, will help. Just one or two drops and let it sit overnight usually works quite well. Or if you can't get to the bearings, what I like to do, is run the hard drive upside down for a time. Sometimes the old grease will liquefy and move to the other side of the bearings and re-lubricate them.
I'd love to give a CRT rejuvenator a shot on one of these tired tubes. I don't have any classic (as this) Macs of my own, though. Hoping to change that some day. Got a Heathkit rejuvenator which worked to restore a 1974 RCA color TV with a dead red gun - now it works bright and clean as new (in 2020 with all original parts!). It might have a dongle compatible with this Mac tube...
That battery probably reverse-charged in some of the cells and got too hot and vented like a bad electrolytic cap. I’m surprised it didn’t catch fire. 😬
It's a single cell 3V lithium primary battery, so no multiple cells and no charge. Simply the seals deteriorate over time, and they leak. The rust above the battery might be caused by the fumes of the electrolyte.
My humble opinion. Take the chasis to a mechanic/body shop and ask them to run it through their sand blaster, then you can treat it with anything to keep future corrosion down, and BAM, ya saved it!
My Mac was upgraded with 2 4MB SIMM modules from memoryx dot com for about $12 total. Also installed the SCSI2SD adapter since the SCSI drive was so dang loud.
Yes number 4!!!! The PSU of my worn out Performa 630 has issues but watching these series makes me want to tackle it :)!
Just like Johnny 5, Mac #5 sacrificed itself for our benefit.
I was chuckling as he took it apart, because I kept hearing "No disassemble Number Five!"
Real number 5 is hidden under the floor... Haha
Have totally loved this series
FYI, you can rehab the rusty chassis by letting it sit in Apple Cider Vinegar overnight. I did this with my Mac SE/30 and it worked great.I ended up using apple cider vinegar and Barkeep's Friend to remove all the rust. Then I sprayed the chassis with primer. Looks great now!
*Of course* Apple had to develop a *proprietary* super expensive vinegar to clean rust in Macs! (/sarcasm) .-D
On HDD #5 you can open it and unstick the back of the arm. As the bumper material degraded over 30 years it gets sticky and prevents the arm from moving properly. I've had more than a few suddenly spring back to life by carefully pulling the arm off the platter. You can't really trust the drive after that but it's a useful trick to create a narrow window of opportunity to pull data off of it. That said, sometimes it just won't work at all.
When fine-adjusting CRTs, we would always have a test-pattern onscreen that also has a circle.
I would suggest after taking a wire brush to the rusty chasse to then use some of the chemical rust converter like rustex (rust is chemically changed to iron phosphate) which then protects the rest of the metal, then a quick spray with some metal primer and you're good to go.
Did you know there are refresh devices for tubes? Like the 'Müter BMR 90'.
How do you fix the yoke in place after setting it right?
Please try saving that chassis and the CRT! You can get a rejuvenator for the CRT. You may not care about the Mac Classic, but we do!
"PP1" on the power rail? What, it's not PPBUS G3H?
LOL!
i totally recognized you Tandy board in the last LGR Video... Adrian (@Adrian's Digital Basement)
at minute 9:31 .. >> ruclips.net/video/FmmN9k7v2_8/видео.html
What’s your plan with the front bezel? I’m thinking a small lcd mounted inside with a raspberry pi.
I can't wait until OLEDs mature to the point where they start making panels that are curved to match picture tubes of the same size. Then people can start repurposing screen housings for even more authentic-looking projects.
@@stevethepocket that will be exciting, although it may be microLED rather than OLED by then (the maturity on curvature for arbitrary CRT curvature, and the panel longevity/burn in reduction - bearing in mind all but Trinitrons are curved in two directions not just one like folding phones)
Can’t wait to watch the candy section of this video...
I love what you do, cause you do it with a lot of passion !
My messages said 3 days ago, but this says 3 years ago. Anyway, it was still great as I just did a CRT replacement myself on my Classic II just tonight, so thanks
Another great video. I especially like how you recycle every part. I hate throwing away tech and wish more RUclipsrs would encourage recycling!
High turning up the brightness may not improve anything because most CRT monitors have a beam limit circuit, so if you increase the brightness it will probably back off the contrast or brightness or both depending on how they implemented it.
If you have a really tired CRT you can try to rejuvenate the CRT, I have had some good results with monochrome CRT's.
It’s such a relief to watch Mac repair without terrible puns, histrionic behavior, constant forced laughter or weird “skits”. Sadly, we have to scroll so far to get here past Mac84, CuhRAAAZY Ken, RetroRecipe and HRUTKAY.
Back in the day i was using scsi... it was fast but loud and they were heaters especially those 15k seagate cheeta drives... 2 15k raided drives had some unbelievable speed.
That rusty chassis is completely salvageable. There are so many easy ways to get rid of rust. You could simply sand or wire wheel it. There are countless rust remover liquids and gels. You could sandblast it. Sonic cleaners work great too. It just seems off for someone who wants to preserve these old computers to just toss away a perfectly usable part.
Really enjoying this series, looking forward to the next part
Good Ole stiction... A lot of my older macs did this if they sat too long. especially with the connor drives... my guess is age isn't kind to the lubricant in the motors, and while you can get them going again, sometimes the drive will stick again at some point.
Always have a mirror in front of the CRY when repairing, so that you can see the front from behind.
Keep up the good work... I hope to resurect my Classic II when I change the caps... The re-cap kit should be in the on the way.. (I dishwashed the MB and two of the caps actually fell of.)
It's so relaxing watching your videos. Sounds like you should be reading an audio book to me lol. Real glad I found your channel man
The hard drive on my IBM 486 does that thing too. If it hasn't been started for a while you have to give it a tap to wake it up. I have heard it called 'sticktion' like stick and friction. Is that a real term? I don't know :-) It's like the bearings are dry. I wonder if they can be lubricated.....mmmm, interesting. Great series. Cheers
Two things. You could easily use rust stop or alternatively sand it off and spray anti corrosion paint. Finally if you must throw away recycle the metal
Adrian, The oxidized chasis just needed to be sandblasted!
These seem quite nice to work on, I might have to buy my first ever Apple product!
These small monochrome CRTs need a TON of hours to go that dim. I've recently bought two 8" monochrome CCTV monitors that was installed in some industrial control system, they were on 24/7 for many years (probably 10+ years), both has horrible burn-in marks on the screen, but they are still as bright as an atomic blast! And those are not Samsung, but Chungwha.
Your CRT might have cathode poisoning, the cause can be the low supply voltage: if you run vacuum tube filaments undervoltage for a long time, you can get cathode poisoning. Don't throw out that CRT, it probably just needs a light rejuventation, I don't think the emissive coating on the cathode got used up, just its surface is deteriorated, which can be cleaned off gently with the right rejuvenator.
Rejuvenation is not a permanent solution, since the tube will get dim again after some time. As youtuber Shango066 once said: "Rejuvenation was just enough to get the customer to shut up until you could order a crt or get him into a new TV". What your saying about cathode poisoning could be somewhat true, but really, wearing out a picture tube doesn't take a lot. Just use it with the brightness set too high and you'll get a dim picture in less that 10 years. The crts you have were probably run with low brightness and that's what saved them.
@@enzoperruccio I'm not a fan of rejuvenation either, and you're right, it is *usually* just a temporary fix - if the CRT is tired, so the emissive coating is worn off, it won't do wonders. BUT it can permanently repair cathode poisoned tubes, unless the poisoning was due to gassiness. It also can permanently repair some tubes with high hours in it, but which has very thick emissive coating on the cathodes, and during its lifetime as the material evaporates, it's getting deposited between the cathode and the G1 element, causing a partial or full short. I've seen rejuvenated CRTs working for 3-5 more years with good picture after rejuventaion. I personally don't have a proper rejuvenator, but even the crude method of applying rectified 230V through a 60W light bulb between the cathode and G1 worked great for me on certain tubes. It kills about half of the tubes, but some will last years even after this crude method (a genuine rejuvenator would give much more consistent results).
After all, the reason why I think this would work with this Mac CRT, is the fact that it has no screen burn. Computers used in industrial/office environment usually show static images, or at least portions of the image is static, so the screen usually develops some burns over its lifetime. That's why I thinking it's not an overused, very high hour CRT, so it can be a good candidate for rejuvenation.
Video quality was very good in this video, great job
there is a bleed resistor on most bucket mac's after the SE (maybe sooner im not an expert at the pre adb machines)
2:40 If the battery did not spray, maybe the vapor itself is enough to cause the corrosion. Just an idea.
I would still replace any electrolytic capacitor I found in any of these systems (analog board or mainboard). These computers were hotboxes from day one, and have just seen too many hours at this point. A modern tiny quiet fan strategically placed near a vent hole couldn't hurt them moving forward either.
AFAIK the classic macs had no thermal issue whatsoever. Replacing caps is always a good choice, though.
I worked in a wafer fab for a few years. We have had an spray etching machine wich used hydrochloric acid. Behind this machine was a wall and on the other side of this wall was a PC. The pure vapur of the acid was engough that this PC must be changed every two years. They where completly corroded after that time.
So I think the vapur of the battry acid did this corrsion.
One thing you can try on the Classic motherboards is booting from the ROM Disk. Just hold down Command-Option-X-O until the system starts to load and you'll be running System 6.0.3 from the ROM. Sadly, it doesn't work on the Classic II motherboard. Also, make sure not to hold the keys all the way to the desktop, otherwise it'll try to rebuild the desktop file, which won't work for fairly obvious reasons.
To be more clear you are adjusting the black level or brightness for the dim setting you are doing and contrast white level for the max setting really.
It's actually not good to adjust the voltage if you suspect that the power supply is faulty because if that solder joint connects by itself you will have bad overvoltage.
TTL voltage specs is 4.75-5.25V if you want to fineadjust 😉
Dim CRT has nothing to do with caps unless B+ is low because one is shorted out or failed open. Low emissions from the electron GUN is more likely due to high hours and electrode vaporization. Check B+ is in spec, check pots for values out of spec. Check voltages on the neck board too. Should be specs out there.
14:13 The resistor of the meter will also bring down the voltage
Can't wait for the next episode. Nice work and well explained and demonstrated :-)
Hi from Aust!. You said that other tube was worn out? Its guns could just need a clean/rejuv. Do you have a CRT Restorer Analyzer? I saved many tubes and they are great if you have old video arcades machines you still run or people need you to restore theirs sometimes.
Great channel and look forward to each riveting instalment of a fix you take on.
Off-topic, but that doughnut shirt is fantastic.
11:20 - actually in the "old days" replacing the tube was a last resort - quicker & cheaper to use a tube rejuvenator... As long as thee is no screen burn it's worth rejuvenating a tired CRT.
The battery wouldn't have sprayed, it's more likely it was from gases emitted from the electrolyte as it evaporated inside the case (along with electrolyte from the caps reacting with it probably), I don't know what gases they would be from a battery as I'm no battery chemistry expert, but chlorine and similar can cause rust like that without contact, such as hydrochloric acid evaporating near steel, that makes things rust fast...
May be the computer lag upside down for some time? Just as an explanation, why there is corrosion also above the battery?
A EEVBlog multimeter, nice!
yo! I’m having a strange issue with my 1998 iMac G3. It works without any problems initially, but when it’s left on for a long time, a weird bug occurs that’s difficult to pinpoint. After being on for an extended period, my iMac G3 simply goes into a black screen mode if there’s any change in video resolution. Additionally, when I turn it off and try to turn it back on, the power LED stays green, never turning off, and the machine doesn’t power back on. The same happens during a reboot; instead of the LED turning yellow and then green, it doesn’t return from the reboot. Even with the startup chime playing, the screen remains black. The only solution is to unplug it and plug it back in. After being unplugged for a while, it returns to normal, but the bug reappears if it’s left on for several hours, typically two or more. I’m not sure if this is an issue with the mainboard, power supply, or analog board. I’ve already recapped 100% of the capacitors, and while the bug used to be permanent, it’s now intermittent. At first, I thought the recap had solved the problem since I only used the iMac for a short time, but when I use it for longer periods, the bug always comes back. It only stabilizes if it’s unplugged for at least 10 hours. Any attempt to turn it back on after the bug appears is futile. Do you recommend checking any specific chip or shutdown signal? Thanks for the help. Oh, I forgot to mention, only the electrolytic capacitors were replaced during the recap.
Ever thought of repurposing that old case for a Hackintosh build?
You could have wire brushed the steel frame and sprayed some Hot Cat Piss (Phosphoric Acid) to neutralized the rust on the metal and spray it on the rest if the frame to protect it. After buffing it with some steel wool, spray it with some Rustolium Chrome paint and buff it to restore it.
Go find the Larry Pina Mac Classic Secrets And Upgrades book. It in .pdf online somewhere. It will tell you the exact specs for the screen image and some basic repairs you are missing.
In the uk we used to get old crt tube reguned so sometimes we could get old tv working when new tubes nort avaliable
There are efforts to bring it back, but the CRT rebuild industry is totally dead right now.
We need more repairathon videos please
Are You able to rejuvenate that tube? Shango066 shows on his channel how to use Beltron/Super Mack CRT testers which have also a rejuvenation function.
If you watched his videos you'll also know it's only a temporary solution, meaning the tube will get dim again after some time (could be hours, days or even weeks, but it will get dim).
Hi From brussels , i realy like your vidéos and i did learn a lot thanks.
Tons of content lately! Great work.
I love this series
Hi Adrian. What’s the status of that corroded board you sprayed with WD-40? Has it caused any additional corrosion, or damage to plastic bits? Are the traces and pads still shiny? And how did you get the WD-40 off?
11:32 boy that took awhile for Adrain to process that xD
HI Adrian, nice fix.. just wondering, on the CRT image it seems a bit small, roughly 1/2" of black around the edges... is the yoke pushed fully forward? That can sometimes cause that as you may know. Other than that maybe screen height and width are set low... the HV seems fine so that cannot be the issue.
Not a huge MAC fan, but a good fix video non-the-less.
It's funny how the CRT stuck around the longest as the specialized vacuum tube, it's siblings are the magic eye tubes (eg. 6E5) and it's "blind" predecessors (diodes, triodes, (kinkless) tetrodes and petagrids)... the CRT evolving out of the electrostatic deflection with the adaptation of external(!) magnetic windings. Fascinating stuff.
(Bonus question, looking back do you ever wonder how someone could do daily work on a CRT screen that small? Seems tiny compared to the LCD panels we have now. Still, nothing beats FPS on a large CRT.)
Cheers, hope you are staying safe now.
When the yoke isn't in the right position the corners of image get cut off ... the size is simply an adjustment on the back of the machine. And yeah the tube is just a vacuum that stuck around in the 2000s. Funny really! As for small CRTs-- it's not that much of an issue when you are only running one program at a time. But similarly I can get actual work done on my 6" phone if I need to. :-)
Just out of curiosity, is the rusted chassis and the plastic housing for sale? I've been looking for a Macintosh to build a PC inside of, but I didn't want to decommission a working one or a good-condition chassis that could be used to repair one.
just a question. Could you still salvage those parts? Being that there aren't many of those computers around? the rust. if not too bad could be ground out of the metal right?
I have a dumb question possibly, what is the horizontal line that goes down the screen periodically
IIRC, SCSI hard drives will go through their startup and if they don't see a bus signal, will spin back down... but then that doesn't explain the further spin up-stay up afterwards...
For that metal chassis, why not see what a sandblaster can do to that corrosion? I bet it'd strip it all away almost effortlessly.
That black Røde box must be a microphone. At first I thought you were wearing a dosimeter!