A few months ago, I found an Apple IIc at a recycling center in a very similar state. The bottom was just a brown mass of rust and goo. After seeing all your videos, I thought "what the heck" and took it home. Inside it was even worse. The RF shield had completely eaten through in most places with just a tiny bit of shiny metal left and all the ports were solid rust. The infamous keyboard rubber mat had turned to dust. Still, I'd seen you recover worse, so I pushed on. The floppy drive had rust and insect corpses pouring out of the slot and there was a disk inside that had fused to the innards. Surprisingly, the rubber belt (that usually turns to dust or goo) was intact. Long story short ("too late!"), after a lot of de-oxit and IPA and rust remover, I plugged it in and it mostly worked fine! The biggest shocker was after thoroughly cleaning the floppy drive and re-greasing the components, it also worked. This was the ultimate goal since I had a stash of about 40 floppy disks from the mid-80s with no way to read them. 5 1/4 floppy drives are getting very rare and ones that can work with Apple II disks with something like a kryoflux are even rarer. And another shocker was of the 40 floppies only two were unreadable. Not bad for 35+ year old magnetic media. It was quite a joy to re-discover some computer projects from my grade school days and archive them. Now I can run them in an Apple II emulator and show my nieces and nephews "This is what your uncle had in school when computers were new". So thanks for the inspiration and maybe check if that floppy drive still works. You might be surprised.
Mouse and that mouldy joystick are worth a shot as well. Though i guess it's good to disassemble it outside and maybe dip it into miconazol just in case :D
Curious how you archived the floppies? I have boxes worth also from the '80s. Still have my Apple ][ Plus, //e, and IIGS, but would be good to be able to access the disk images from an emulator.
@@orbitalgolem91 If you have working Apples you can use ADTPro to transfer data to a modern system. You'll need a serial cable but this shouldn't be hard to obtain.
@@the_kombinator Exactly what I did. I got some blank disks and then transferred known good disk images from a PC to the Apple IIc via ADTPro. Those booted fine. Then I had ADTPro read the same disk and transfer that image back to the PC and verified it was byte-identical to the original. Then I went through my disks in order of least importance (just in case the functionality was intermittent) and imaged them to the PC. I'd seen videos of people preserving old magnetic media where as they were being read for the final time, the oxide would come off, so I acted as though I had one shot to do this. In the end I had a lovely time capsule of the 80s including an ancient AppleWorks database of my old comic book collection (and realized the box is still buried in tupperware bin in my parent's basement appreciating in value).
They are rotten, cleaning will help but the rotten sockets will likely cause instabilities later on. Especially if the Amiga is back in its case (it can get cozy warm inside). They all have to go. Sockets are a common problem on all THT-Amigas, even the ones that have not spent many years outside. ^^
Tonight Adrian made me sick to my stomach as he said battery in the memory expansion. Run to the basement I checked my Amiga and sure enough the battery in it just started leaking thank God it did not touch the board!!!! Lol. 😅 Thank you Adrian!!
I do appreciate Adrian's taking the "long way" to fix something in an attempt to teach us. This way we can see how the system reacts when various components arn't functioning properly. The final lesson if you find a computer in this type of condition, check and clean the chips and sockets before bothering to turn in it. Granted Adrian could have done that and gave us a 10 minute video but then we would have missed out on quite a bit of info. Amazing how he can be given a computer from somebody that sat on a shelf for years, and turns out to be a total bust, then dig up some thing from a field and up and running within a day. Boggles my mind.
I noticed a resistor network next to the Gary chip surrounded by corrosion and thought surely it was causing grief. Apparently not! Go figure. Looking forward to part 2.
I think a lot of people originally found this channel from that C64 video - I know I did. Always fascinating to see that things like this can still be salvageable!
The first thing to do that every Amiga 500 owner should know is to re-seat all custom chips. Take them out and just reinsert them. Better yet, check all socketed chips on a working Amiga motherboard. Regardless, I like all the videos you do
My high school's TV studio class was still using an Amiga 500 and Amiga 2000 Video Toaster in 2002 when I graduated. We used the video toaster as a switcher and the Amiga 500 was used for creating title graphics. I have no other experience with this platform, and I very much would like to see more about it. Thank you Adrian! ❤
To correctly boot, the OVL (overlay signal) should work. It enables the Kickstart ROM overlay at address 0 through Gary's address decoding (OVL -> ROMEN). The OVL signal is coming from one of the CIAs.
Haha most of us were yelling at the screen about those darn sockets. How about the duribility of that old crusty rained on amiga WOW. I really enjoy your repair videos. Its very relaxing going through the process of troubleshooting.
A friend of mine had one of those Amiga 500 years ago. Class games on it back then. Alien syndrome, was one. Shadow the beast was another, (great graphics for the time, & at the very start run left to the last hill and stand on top behind the tree and type in "ten pints" infinite energy) turacan was another cool game. St' dragon, the list goes on. God this brings back memories 😊👍🇮🇪🙏
this series its better then every "netflix" series..! drama, sadness, fun, disappointment and happiness. like a journey through the feelings of a retro - hobbyist.🙂 thanks for upload, and a commodore can never rain,snow and mud stoppin..(ol).🙂..sorry for my bad english...have a nic pre-x-mas time and to all retrofreaks...your KrautRockt!er from chemnitz/germany
And that's how I know I've been watching your channel for about five years. The field found C64 was one of the first of your videos I watched. Here's to five more!
Still have my Commodore Amiga 500 with all the hardware, did buy the A500 when it came out. Have even the original KSC500 powerboard. I'm very happy my A500 with all the hardware still looks as new.
Commodore made some tough machines! (excluding most MOS chips) I laughed when you showed the battery thinking for once that was the LEAST of your problems in getting a machine working. 🤣
I was screaming “just clean all legs and sockets!” at the screen, but it was still interesting to watch the full video. That said for the longevity of the machine I would still replace all sockets and caps given their low quality even when they were new combined with the state they are in
Great video Adrian. You need to give this Amiga so much love. Would be nice to see all the sockets, rear connectors etc repaired/replaced and the case and keyboard cleaned up and everything put back together as much as possible. It deserves to live and have a bright future!
I know it's a small thing but thank you for linking to the next parts, not just mentioning them in the video! Very refreshing to see. So many channels on RUclips make you search though their catalog of videos without parts numbers to find some mystery part 2 that may or may not exist.
Adrian please stay exactly in this style of troubleshooting what you mentioned at the end. It is exactly why I like your videos. You dig deeper and deeper until you find the problematic component. Also I like your comments on findings while you edit and cut the stuff (this ROM topic). Stay in this mood and style and your videos will be fantastic as they were in the past. I also found your channel with the field found c64 and now you have a field found Amiga 500. Fantastic Thanks for this content, best wishes
To help your toothbrush action you should get an old/cheap electric tooth brush. When the battery died in mine I bought a new one, replaced the battery on the old one and made it a permanent fixture on my electronics bench. It works really well for cleaning flux and corrosion.😊
It always amazes me what electronics can survive through. Both watching the restoration of the field-found C64 and this field found Amiga proves the electronics and ICs are far more resilient than we give them credit for. Love to see more of this content, but at the same time I cringe when I see these things getting left in fields.
Diagrom is a 512K rom. The board is a rev 5, which has a wireing bug under the kickstart socket, hindering accessing the uppermost address bit. That's why you got no screen, using the tool
If you can find some in your area, get an aerosol, drip can, or spray bottle of Kroil from Kroil Labs (formerly Kano Labs). Expensive, but one of the best penetrants on the market. That may have made separating the original RCA jacks a bit easier. Kroil is an "active" penetrant, and will bust that rust for ya. Tons better than WD-40. Some CRC Zinc-it cold galvanizing spray will take care of those metal surfaces once the rust is removed with a wire brush or that dremel tip you're so fond of. A little sprayed into a cup and then brushed on will get the small stuff like D-sub shells, but be sparing with it when brushed on. Your approach to troubleshooting is systematic - don't listen to those who advocate a "shotgun" approach. I would, at some time in future, consider replacing some of the sockets (notably the PLCC socket for the Agnus) that were really crunchy , but for now all seems to be working. I'd also think about installing sockets for the RAM to make future troubleshooting easier, but that's just me. Do consider getting caps of the correct value to replace those 1,000 microfarad ones you installed. That would likely be better for the long-term health of the board.
leaving an Amiga on for days seems to improve things some times. I forgot mine for a day during a really hot period (Mediterranean Summer) and a noise coming from the sound circuit disappeared!
I recently received and Amiga 500 that was sitting in a barn in germany for 30 years and survived shipping to the US, it was in similar (though not quite as bad) condition as this Amiga and it's pretty amazing how much a good cleaning can take these old machines from completely non-functional to running perfectly! Always great to see these machines restored! ^_^/
I love your enthusiasm when something "freaking works", those machines are so resilient. The only problem is when I watch your Amiga videos I end up browsing places online to find an Amiga! So far I have resisted...... Mainly because they're quite pricey!!
Great work Adrian, love seeing Amiga rescues. It is pretty surprising how little was wrong with it, some videos that I have seen with battery corrosion have been so much worse.
Exactly right at the end! I have two Amiga 500 a friend of mine wants me to have a look at (I don't have much experience, so I'm being super careful) and videos like you make with the details and finding out the why, is vital. Thanks so much!
I still have my a500. Used when was a kid and stop working about 1997. Abour 2 years tried and give a full clean ( litteray competly soaked) in wd40... Works like a dream
I enjoyed this journey into Amiga hardware. I'm glad that you looked at the boot process in detail, as it's always been mysterious to me. Not only do the 'failure colours' vary between OS revisions but there is so much that is undocumented - and that weird purple early boot screen was a classic. Also, the process of investigating the problem often makes it a) get worse or b) disappear - a 'heisenbug'. I've seen many of these while debugging electronics.
Thank you Adrian......am living in an apartment with no space to move around....let alone have a work bench! Your channel provides a much needed booster shot of troubleshooting and retro computing. Really appreciate your time involved in making these videos.
I have a warm spot for the Amiga. I rediscovered mine in the loft this year and passed it on to an enthusiast restorer. Oh, and a mouse had made a nest in it. Having restored an electric piano with cat urine problems, I didn't want to take that one.
That A500 is an early revision too. Early OCS Denise chips do not start up with a consistent display colour - I have one here that always starts up with a brown screen. It's also possible that the chip data bus issue is preventing writes to Denise which would reset the colour registers.
Omg, stumbled onto this channel and video, and it’s brought back so many memories of my A500 and the A1200. It’s how I started as a software developer. Absolutely loved watching this video. Well done good sir, bringing life back into old hardware. I tip my hat to you good man.
I have to admire your optimism :-) I would probably just have pulled all the socketed chips out and tested them separately on a known good machine and then ripped all the sockets and out of the board and left it for later.
I repaired literally hundreds of Amiga, C64 and C128(D) devices for living when they were sold. Your video just reminded me on these great years :) Thank you!
I'm definitely curious to see what, if anything, you plan to do about the beyond-repair metal shields. I wonder if anyone has taken the time to take measurements and make CAD files people can send off to a place like OSH Cut to make replacements, like how there are 3D printing files for a lot of plastic components.
“These sockets are really gross and probably are keeping it from working” “I wonder what’s causing this strange activity?” *cleans sockets* “WOAH WHAT?? ITS WORKING??”
Reminds me of Dr. Frankenstein shouting: "IT'S ALIVE!". There is something fascinating about bringing tech history to life. I'm old enough to have worked on Varian mainframes with ferrite bead core memory, and Xerox Diablo 1mb disk drives. Amazing what was done with so little. I don't think I would bother trying to restore any of that though. HA!
The Amiga 500 also makes a great complete all games mod laptop. Even creating an Amiga controller with 2, 4, or 6 buttons as an option might be a suggestion.
Regarding Gary, i guess it does help to know the Amiga quite well to understand what it's doing. Gary largely does address decoding, and CPU bus handling. One important thing with Gary, and you often find this on Varta'd boards, is that the _DTACK signal is very important. Every bus cycle on the 68000 has to be terminated by DTACK, and if it isnt the CPU will just sit there. Gary actually uses this fact to stop chip ram being used by the CPU when the custom chips use it. A17-A23 inputs do pretty much all of the system decoding - if theyre all low, a chip ram access is assumed (_RAMEN is asserted). If the upper bits are $F8, then _ROMEN is asserted. If the upper bits are $DF, it's a chip register access (_REGEN is asserted). _OVL is for "overlay" which means the ROM is mapped in at address $0 instead of the chip memory, which is needed for the 68000 to read its initial program counter and stack values. _OVR is "override" and is used by external hardware to disable Gary's address decoding during a bus cycle. _OEB, _OEL and _LATCH control the 244/373 chips in the "DATA PATH" part of the circuit. This is basically a "bridge" between the CPU side of the data bus, and the chipset/chip ram side. Typically this bridge is only enabled when the CPU reads/writes chip ram, or reads/writes a custom chip register. There is a text file out there (believed to have come from Dave Haynie) that describes what Gary does. Unfortunately I cant paste a link here.
Great stuff, don't mind the rabbit trail of testing. Yeah cleaning sockets "might" have helped but I agree with you the logic/troubleshooting is a great learning tool.
This is just great stuff! So many side things you learn that can apply to other things and other machines! So many thanks to you Adrian! Appreciate the time you take.
You got to know not everybody loves the Amiga, when they leave it outside for 20 years. I found a Vic-20 once in a landfill. Brought that puppy home, wrote a little cassette disk OS boot loader for it, and gave it away to a friend. They then abandoned it yet again and left it behind when they moved out of an apartment. I was so mad. I think I went to pick it up when the office manager called me. After that I probably gave it away yet again in a care package to some poor Commodore nerd on the old ISCA BBS. By that time I was swimming in hundredss of computers.
Yay! Another one saved, well hopefully in Part 2 well know for sure.. Good job. I recently found and saved an Amiga 500 and commodore 1084 from a barn as well that was left for dead 23 years ago. Sadly the 1084 monitors flyback went byebye but the Amiga 500 is doing well today. Love all your videos Adrian, cheers from Sweden!!
Citric acid or vinegar will remove the rusty stains on the PCB and case. Keep it to the areas necessary on the PCB and rinse off well. Evaporust should work well on the metal shields.
"Left outside for years" but the plastic isn't ruined from weathering, the only color on the case is from minimal cigarette smoke and not from dirt and weather or anything. The rust is probably painted on. This actually looks like it spent all of its life in box in a closet in the home of a smoker. The plastic would be cracked and bvroken and would be extremely filthy from weather, but it's not. This is really clean.
2:20 - I would have cut all the soft foam off the joystick and checked to see if the innards could be saved. 3:54 - Judging by the sticker, I have that same floppy drive. Funny story: A few months after I got it, the drive would refuse to spin up when I put a disk in it. I took the bottom off and could se the flywheel start to move when I put a disk in, but then it would stick. I found that it worked OK if I gave it a nudge with my finger. I did that for a couple weeks, then it just started working normally. I put the bottom back on and never had any more trouble from it.
Congrats on yet another success. I do have some issues... I get your point about the process, but most people wouldn't have a working Amiga to test against regardless. If they did, the surely the best thing to do would be to first take all the socketed chips and verify that they work in the Known Good machine (if not, then binary searching makes it quick to isolate bad chips). Also I'm surprised you left a lot of rust on the PCB. Looking forward to the next many parts on this, thanks :)
I thought about this too, but then knew how god awful boring that’d be and learned something about how the Amiga works through the schematics. Adrian should just keep the argument to the point the methodology is to logically go through the process, not brute force the solution. Remember, being fast (and efficient), is just worker bee talk. You don’t have time to waste when you’re in an IT job being intelligent, you just re cap and swap everything and take shortcuts to complete the job as quickly as possible and move on to save the company money. If I wanted that I’d just stick only to my day job in IT (which is my least favorite part about it) and not watch Adrian do what I know deep down is the better way to do it. Being intelligent and logically working through an issue. Definitely projecting but your profile pic reminds me of an old senior programmer I worked under. I’d constantly be in trouble with him for spending too much time trying to understand the why and how instead of just slapping a quick fix and moving on….only for an issue to arise later. Such a terrible philosophy. The time and money overall wasted if you’d just put in the correct effort upfront instead of a hack that only exacerbates the issue worse down the line because you didn’t really solve the problem to begin with. Point is, sure, if you don’t have time or the correct tools, just recap and swap/resocket all the chips, but that’s just a lame blanket response and would make a god awful video that would only make a certain senior programmer happy that I hope is no longer in the business. Just because it’s faster or efficient does not mean it’s the best solution.
Learning why a machine isn’t running is valuable and trying to see the problem confirms issues before you have to make drastic decisions like desoldering chips. We could have been dealing here with so many issues like bad traces even, so only chip swapping doesn’t teach anything. As for the rust, it won’t do anything on the PCB so no real reason to remove it IMHO.
Yup, I think if you're a retro youtuber, it's best to go through the proper process to test and determine why things aren't working and show that process because a lot of viewers don't have multiple machines in every situation and it's good to learn the testing proces. However, If you're not doing it for a video and you have a spare machine to test on, of course you'll just do that from the start. As for the rust, I think Adrian still needs to run that motherboard through the dishwasher. :)
@@TechnicolorMammoth Just a comment on the quick fix vs investigating the problem in the workplace. I get both sides of it. Having done IT forever, I come from the time when you would sit and analyze an issue and work to understand, solve and hopefully document it. Nowadays with IT areas such as desktop, the practice is to reimage a machine, not to figure out what's wrong with it. The idea behind that is that rather than spending hours trying to figure out what went wrong with a machine, you can quickly reimage the machine and they'll be back working again. The issue with trying to fix the problem is that you may think you solved the issue and possibly didn't get all the issues of the problem and could cause multiple revisits and issues down the line. An example might be a computer infected with a virus, you don't really try to fix it, you wipe out the machine and start from scratch. Anyway, this doesn't apply to as much to hardware like adrians videos or even areas where you're both the user and the repair guy, but I can see how it is different in the workplace.
Ι use a special tip for the soldering iron and melted plastic from a ziplock to reattach the keyboard in such cases.Provided the customer is willing to pay a premium for the labour.
Meanwhile I am watching this on a 5820k system I found in trash years ago. Motherboard was entirely covered with mud and lying bare with a heap of other electronic scrap and yet been extremely reliable and even came with 16 gigs of ram. Some of my previous systems have similar stories...
Thank you for the good videos . Next time start measuring the onboard power levels because I would not hesitate assuming most of the problems where related to the two capacitors.
A few months ago, I found an Apple IIc at a recycling center in a very similar state. The bottom was just a brown mass of rust and goo. After seeing all your videos, I thought "what the heck" and took it home. Inside it was even worse. The RF shield had completely eaten through in most places with just a tiny bit of shiny metal left and all the ports were solid rust. The infamous keyboard rubber mat had turned to dust. Still, I'd seen you recover worse, so I pushed on. The floppy drive had rust and insect corpses pouring out of the slot and there was a disk inside that had fused to the innards. Surprisingly, the rubber belt (that usually turns to dust or goo) was intact. Long story short ("too late!"), after a lot of de-oxit and IPA and rust remover, I plugged it in and it mostly worked fine! The biggest shocker was after thoroughly cleaning the floppy drive and re-greasing the components, it also worked. This was the ultimate goal since I had a stash of about 40 floppy disks from the mid-80s with no way to read them. 5 1/4 floppy drives are getting very rare and ones that can work with Apple II disks with something like a kryoflux are even rarer. And another shocker was of the 40 floppies only two were unreadable. Not bad for 35+ year old magnetic media. It was quite a joy to re-discover some computer projects from my grade school days and archive them. Now I can run them in an Apple II emulator and show my nieces and nephews "This is what your uncle had in school when computers were new". So thanks for the inspiration and maybe check if that floppy drive still works. You might be surprised.
Mouse and that mouldy joystick are worth a shot as well. Though i guess it's good to disassemble it outside and maybe dip it into miconazol just in case :D
Curious how you archived the floppies? I have boxes worth also from the '80s. Still have my Apple ][ Plus, //e, and IIGS, but would be good to be able to access the disk images from an emulator.
I would be careful putting anything into that drive that you care about - throw some disposable diskettes at it first!
@@orbitalgolem91 If you have working Apples you can use ADTPro to transfer data to a modern system. You'll need a serial cable but this shouldn't be hard to obtain.
@@the_kombinator Exactly what I did. I got some blank disks and then transferred known good disk images from a PC to the Apple IIc via ADTPro. Those booted fine. Then I had ADTPro read the same disk and transfer that image back to the PC and verified it was byte-identical to the original. Then I went through my disks in order of least importance (just in case the functionality was intermittent) and imaged them to the PC. I'd seen videos of people preserving old magnetic media where as they were being read for the final time, the oxide would come off, so I acted as though I had one shot to do this. In the end I had a lovely time capsule of the 80s including an ancient AppleWorks database of my old comic book collection (and realized the box is still buried in tupperware bin in my parent's basement appreciating in value).
It's pretty impressive how resilient electronics can be.
Back when planned obsolescence wasn't a thing (to the extent it is today)
Especially something that was made as cheaply as possible!
Car manufacturers take note.
Cars are designed and tested to be left outside.
Ikr. Especially when it's made with quality parts.
So the main takeaway here is:
Always clean *all* the sockets and chip legs first before you do any testing
It's like the new version of the "check if it's plugged into the wall" advice :D
I would completely 100% agree, remove all chips, clean and deoxit, reinsert, then start tests. Save a bunch of time.
No, clean them before doing other _troubleshooting._
They are rotten, cleaning will help but the rotten sockets will likely cause instabilities later on. Especially if the Amiga is back in its case (it can get cozy warm inside).
They all have to go. Sockets are a common problem on all THT-Amigas, even the ones that have not spent many years outside. ^^
Yep, have a system to follow, otherwise you are just trying to lay a carpet with all the furniture still in the room.
Tonight Adrian made me sick to my stomach as he said battery in the memory expansion. Run to the basement I checked my Amiga and sure enough the battery in it just started leaking thank God it did not touch the board!!!! Lol. 😅 Thank you Adrian!!
Another patient brought back to life at your Amiga hospital. Amazing work!
I do appreciate Adrian's taking the "long way" to fix something in an attempt to teach us. This way we can see how the system reacts when various components arn't functioning properly. The final lesson if you find a computer in this type of condition, check and clean the chips and sockets before bothering to turn in it. Granted Adrian could have done that and gave us a 10 minute video but then we would have missed out on quite a bit of info. Amazing how he can be given a computer from somebody that sat on a shelf for years, and turns out to be a total bust, then dig up some thing from a field and up and running within a day. Boggles my mind.
It never gets old seeing you get excited when it starts working. Thanks Adrian.
I noticed a resistor network next to the Gary chip surrounded by corrosion and thought surely it was causing grief. Apparently not! Go figure. Looking forward to part 2.
I kept looking at that & thinking the same thing...
I think a lot of people originally found this channel from that C64 video - I know I did. Always fascinating to see that things like this can still be salvageable!
For this type of sockets, always clean the chip pins from BOTH sides, especially from the inner side.
The first thing to do that every Amiga 500 owner should know is to re-seat all custom chips. Take them out and just reinsert them. Better yet, check all socketed chips on a working Amiga motherboard. Regardless, I like all the videos you do
Thanks!
My high school's TV studio class was still using an Amiga 500 and Amiga 2000 Video Toaster in 2002 when I graduated. We used the video toaster as a switcher and the Amiga 500 was used for creating title graphics. I have no other experience with this platform, and I very much would like to see more about it. Thank you Adrian! ❤
Video toaster was in use for a surprisingly long time.
To correctly boot, the OVL (overlay signal) should work. It enables the Kickstart ROM overlay at address 0 through Gary's address decoding (OVL -> ROMEN). The OVL signal is coming from one of the CIAs.
Haha most of us were yelling at the screen about those darn sockets. How about the duribility of that old crusty rained on amiga WOW. I really enjoy your repair videos. Its very relaxing going through the process of troubleshooting.
The field-found 64 was what got me into your channel, so happy to see the return of computers rescued from the elements!
Thank you for these videos!!❤ learning so much from your detailed analysis with schematic and the scope 👍
Take a drink every time Adrian says 'crunchy'. 🤣🤣🤣
That poor Amiga but Adrian does it again. IT FREAKIN' WORKS!!!!!
A friend of mine had one of those Amiga 500 years ago. Class games on it back then. Alien syndrome, was one. Shadow the beast was another, (great graphics for the time, & at the very start run left to the last hill and stand on top behind the tree and type in "ten pints" infinite energy) turacan was another cool game. St' dragon, the list goes on.
God this brings back memories 😊👍🇮🇪🙏
30:33 - lol at the CRUNCH when you put the chip back into the socket
Thanks for the video - this gives me hope for my old A500, which has not been left outside 🙂
Watching the first 5min, I felt real physical pain watching this poor, poor Amiga! Thank you for trying to safe that poor thing!
I jumped on the notification like a Hawk. Looking forward to another Amiga repair
The robot voice in the “Denise” and “intro” 50:08 had me laughing out loud for a minute there 😂
this series its better then every "netflix" series..! drama, sadness, fun, disappointment and happiness. like a journey through the feelings of a retro - hobbyist.🙂 thanks for upload, and a commodore can never rain,snow and mud stoppin..(ol).🙂..sorry for my bad english...have a nic pre-x-mas time and to all retrofreaks...your KrautRockt!er from chemnitz/germany
Computer on shelf: my caps and transitions are dying
Computer on field: what a splendid natural environment.
And that's how I know I've been watching your channel for about five years. The field found C64 was one of the first of your videos I watched. Here's to five more!
Nice to see you working on my all time fave computer.
I really like your repair style! Anyone can shotgun everything, but actually figuring things out takes work and is for sure, educational!
Still have my Commodore Amiga 500 with all the hardware, did buy the A500 when it came out. Have even the original KSC500 powerboard. I'm very happy my A500 with all the hardware still looks as new.
Commodore made some tough machines! (excluding most MOS chips) I laughed when you showed the battery thinking for once that was the LEAST of your problems in getting a machine working. 🤣
I was screaming “just clean all legs and sockets!” at the screen, but it was still interesting to watch the full video. That said for the longevity of the machine I would still replace all sockets and caps given their low quality even when they were new combined with the state they are in
Love the share!! When the computer booted I was just as excited as you!!
Love seeing lot of Amiga 500 content lately on the basement. I learned one thing for sure, “Deoxit the socket”! 😂
Great video Adrian. You need to give this Amiga so much love. Would be nice to see all the sockets, rear connectors etc repaired/replaced and the case and keyboard cleaned up and everything put back together as much as possible. It deserves to live and have a bright future!
I know it's a small thing but thank you for linking to the next parts, not just mentioning them in the video! Very refreshing to see. So many channels on RUclips make you search though their catalog of videos without parts numbers to find some mystery part 2 that may or may not exist.
Adrian please stay exactly in this style of troubleshooting what you mentioned at the end. It is exactly why I like your videos. You dig deeper and deeper until you find the problematic component. Also I like your comments on findings while you edit and cut the stuff (this ROM topic).
Stay in this mood and style and your videos will be fantastic as they were in the past.
I also found your channel with the field found c64 and now you have a field found Amiga 500. Fantastic
Thanks for this content, best wishes
Your fault diagnostic was brilliant, dont just jump to cleaning sockets thats boring. Excellent stuff
This si pure happines! Really! I sed to be in similar situations and I can clearly understand how does that feel!
Wonderful video. A500 + (later) C= ram expansion was my first home computer.
The Amiga 500 will always be the most beautiful design computer it's defined the 80s and 90s gaming . Amiga forever.
To help your toothbrush action you should get an old/cheap electric tooth brush. When the battery died in mine I bought a new one, replaced the battery on the old one and made it a permanent fixture on my electronics bench. It works really well for cleaning flux and corrosion.😊
It always amazes me what electronics can survive through. Both watching the restoration of the field-found C64 and this field found Amiga proves the electronics and ICs are far more resilient than we give them credit for. Love to see more of this content, but at the same time I cringe when I see these things getting left in fields.
Diagrom is a 512K rom. The board is a rev 5, which has a wireing bug under the kickstart socket, hindering accessing the uppermost address bit.
That's why you got no screen, using the tool
If you can find some in your area, get an aerosol, drip can, or spray bottle of Kroil from Kroil Labs (formerly Kano Labs). Expensive, but one of the best penetrants on the market. That may have made separating the original RCA jacks a bit easier. Kroil is an "active" penetrant, and will bust that rust for ya. Tons better than WD-40.
Some CRC Zinc-it cold galvanizing spray will take care of those metal surfaces once the rust is removed with a wire brush or that dremel tip you're so fond of. A little sprayed into a cup and then brushed on will get the small stuff like D-sub shells, but be sparing with it when brushed on.
Your approach to troubleshooting is systematic - don't listen to those who advocate a "shotgun" approach.
I would, at some time in future, consider replacing some of the sockets (notably the PLCC socket for the Agnus) that were really crunchy , but for now all seems to be working. I'd also think about installing sockets for the RAM to make future troubleshooting easier, but that's just me.
Do consider getting caps of the correct value to replace those 1,000 microfarad ones you installed. That would likely be better for the long-term health of the board.
leaving an Amiga on for days seems to improve things some times. I forgot mine for a day during a really hot period (Mediterranean Summer) and a noise coming from the sound circuit disappeared!
The restoration of the field found c64 were one of my favorite videos from you. So I'm really excited for this video
Nothing quite like bringing an Amiga back to life !
I recently received and Amiga 500 that was sitting in a barn in germany for 30 years and survived shipping to the US, it was in similar (though not quite as bad) condition as this Amiga and it's pretty amazing how much a good cleaning can take these old machines from completely non-functional to running perfectly! Always great to see these machines restored! ^_^/
I love your enthusiasm when something "freaking works", those machines are so resilient. The only problem is when I watch your Amiga videos I end up browsing places online to find an Amiga! So far I have resisted...... Mainly because they're quite pricey!!
Which places do you browse?
Great work Adrian, love seeing Amiga rescues. It is pretty surprising how little was wrong with it, some videos that I have seen with battery corrosion have been so much worse.
Exactly right at the end! I have two Amiga 500 a friend of mine wants me to have a look at (I don't have much experience, so I'm being super careful) and videos like you make with the details and finding out the why, is vital. Thanks so much!
brilliant as ever Adrian - keep up the ace work/videos
Adrian + an Amiga is an automatic thumbs up
I still have my a500. Used when was a kid and stop working about 1997. Abour 2 years tried and give a full clean ( litteray competly soaked) in wd40... Works like a dream
I loved my Amiga, I still have one with the big brick hard drive and boxes of games 😊
I enjoyed this journey into Amiga hardware. I'm glad that you looked at the boot process in detail, as it's always been mysterious to me. Not only do the 'failure colours' vary between OS revisions but there is so much that is undocumented - and that weird purple early boot screen was a classic. Also, the process of investigating the problem often makes it a) get worse or b) disappear - a 'heisenbug'. I've seen many of these while debugging electronics.
Thank you Adrian......am living in an apartment with no space to move around....let alone have a work bench! Your channel provides a much needed booster shot of troubleshooting and retro computing. Really appreciate your time involved in making these videos.
I have a warm spot for the Amiga. I rediscovered mine in the loft this year and passed it on to an enthusiast restorer. Oh, and a mouse had made a nest in it. Having restored an electric piano with cat urine problems, I didn't want to take that one.
Deoxit rocks. Your approach is excellent.
i was definitely screaming at the screen "JUST DEOXIT ALL THE SOCKETS". i appreciate that you're more thorough than that.
That's pretty amazing :)
That A500 is an early revision too. Early OCS Denise chips do not start up with a consistent display colour - I have one here that always starts up with a brown screen. It's also possible that the chip data bus issue is preventing writes to Denise which would reset the colour registers.
Omg, stumbled onto this channel and video, and it’s brought back so many memories of my A500 and the A1200. It’s how I started as a software developer.
Absolutely loved watching this video. Well done good sir, bringing life back into old hardware. I tip my hat to you good man.
I have to admire your optimism :-) I would probably just have pulled all the socketed chips out and tested them separately on a known good machine and then ripped all the sockets and out of the board and left it for later.
I repaired literally hundreds of Amiga, C64 and C128(D) devices for living when they were sold. Your video just reminded me on these great years :) Thank you!
I'm definitely curious to see what, if anything, you plan to do about the beyond-repair metal shields. I wonder if anyone has taken the time to take measurements and make CAD files people can send off to a place like OSH Cut to make replacements, like how there are 3D printing files for a lot of plastic components.
Short version of this almost one hour video:
1:12 - I don't know if this thing will working at all
46:57 - Oh my God! It's freaking work!
😊
“These sockets are really gross and probably are keeping it from working”
“I wonder what’s causing this strange activity?”
*cleans sockets*
“WOAH WHAT?? ITS WORKING??”
Diggin the increased Amiga content lately!
Wow... I can't believe its been 5 years. That was one of your first big videos.
It was that field found C64 that got me onto your channel, looking forward to the sequel!
Reminds me of Dr. Frankenstein shouting: "IT'S ALIVE!". There is something fascinating about bringing tech history to life. I'm old enough to have worked on Varian mainframes with ferrite bead core memory, and Xerox Diablo 1mb disk drives. Amazing what was done with so little. I don't think I would bother trying to restore any of that though. HA!
Congratulations on getting this working. I really enjoyed the journey from non-functional to showing the kickstart screen.
Commodore !! Built to last a life time !. No questions asked !.
The Amiga 500 also makes a great complete all games mod laptop. Even creating an Amiga controller with 2, 4, or 6 buttons as an option might be a suggestion.
This video looks a lot like those "restoration videos" out there except one thing: yours is real! 😂
Thanks for the vid! Was fun warching it
Just found this channel and am loving it. Subbed.
Regarding Gary, i guess it does help to know the Amiga quite well to understand what it's doing. Gary largely does address decoding, and CPU bus handling. One important thing with Gary, and you often find this on Varta'd boards, is that the _DTACK signal is very important. Every bus cycle on the 68000 has to be terminated by DTACK, and if it isnt the CPU will just sit there. Gary actually uses this fact to stop chip ram being used by the CPU when the custom chips use it.
A17-A23 inputs do pretty much all of the system decoding - if theyre all low, a chip ram access is assumed (_RAMEN is asserted). If the upper bits are $F8, then _ROMEN is asserted. If the upper bits are $DF, it's a chip register access (_REGEN is asserted).
_OVL is for "overlay" which means the ROM is mapped in at address $0 instead of the chip memory, which is needed for the 68000 to read its initial program counter and stack values.
_OVR is "override" and is used by external hardware to disable Gary's address decoding during a bus cycle.
_OEB, _OEL and _LATCH control the 244/373 chips in the "DATA PATH" part of the circuit. This is basically a "bridge" between the CPU side of the data bus, and the chipset/chip ram side. Typically this bridge is only enabled when the CPU reads/writes chip ram, or reads/writes a custom chip register.
There is a text file out there (believed to have come from Dave Haynie) that describes what Gary does. Unfortunately I cant paste a link here.
Adrian, the PAULA chip also handles the TX and RX lines of the serial port, so you need a functioning PAULA chip to see anything on the serial port.
Great stuff, don't mind the rabbit trail of testing. Yeah cleaning sockets "might" have helped but I agree with you the logic/troubleshooting is a great learning tool.
While I love everything you produce, this is the kind of content I enjoy the most. Great stuff.
This is just great stuff! So many side things you learn that can apply to other things and other machines! So many thanks to you Adrian! Appreciate the time you take.
Man you're so lucky. I wish I could find randomly abused commodores laying around that I could fix up and use.
You got to know not everybody loves the Amiga, when they leave it outside for 20 years.
I found a Vic-20 once in a landfill. Brought that puppy home, wrote a little cassette disk OS boot loader for it, and gave it away to a friend. They then abandoned it yet again and left it behind when they moved out of an apartment. I was so mad. I think I went to pick it up when the office manager called me. After that I probably gave it away yet again in a care package to some poor Commodore nerd on the old ISCA BBS. By that time I was swimming in hundredss of computers.
Adrian this is awesome!!!! You save an A500 ❤❤❤❤
Yay! Another one saved, well hopefully in Part 2 well know for sure.. Good job. I recently found and saved an Amiga 500 and commodore 1084 from a barn as well that was left for dead 23 years ago. Sadly the 1084 monitors flyback went byebye but the Amiga 500 is doing well today. Love all your videos Adrian, cheers from Sweden!!
Citric acid or vinegar will remove the rusty stains on the PCB and case. Keep it to the areas necessary on the PCB and rinse off well. Evaporust should work well on the metal shields.
I'm not at all surprised that it worked right away after cleaning the sockets. Unlike some computers, A500s just seem to want to live.
"Left outside for years" but the plastic isn't ruined from weathering, the only color on the case is from minimal cigarette smoke and not from dirt and weather or anything. The rust is probably painted on. This actually looks like it spent all of its life in box in a closet in the home of a smoker. The plastic would be cracked and bvroken and would be extremely filthy from weather, but it's not. This is really clean.
2:20 - I would have cut all the soft foam off the joystick and checked to see if the innards could be saved.
3:54 - Judging by the sticker, I have that same floppy drive. Funny story: A few months after I got it, the drive would refuse to spin up when I put a disk in it. I took the bottom off and could se the flywheel start to move when I put a disk in, but then it would stick. I found that it worked OK if I gave it a nudge with my finger. I did that for a couple weeks, then it just started working normally. I put the bottom back on and never had any more trouble from it.
Thoroughly enjoyed this video. I was a proud owner of an Amiga 500 with the RAM expansion back in the day. The memories! :)
Congrats on yet another success. I do have some issues... I get your point about the process, but most people wouldn't have a working Amiga to test against regardless. If they did, the surely the best thing to do would be to first take all the socketed chips and verify that they work in the Known Good machine (if not, then binary searching makes it quick to isolate bad chips). Also I'm surprised you left a lot of rust on the PCB. Looking forward to the next many parts on this, thanks :)
I thought about this too, but then knew how god awful boring that’d be and learned something about how the Amiga works through the schematics. Adrian should just keep the argument to the point the methodology is to logically go through the process, not brute force the solution. Remember, being fast (and efficient), is just worker bee talk. You don’t have time to waste when you’re in an IT job being intelligent, you just re cap and swap everything and take shortcuts to complete the job as quickly as possible and move on to save the company money. If I wanted that I’d just stick only to my day job in IT (which is my least favorite part about it) and not watch Adrian do what I know deep down is the better way to do it. Being intelligent and logically working through an issue. Definitely projecting but your profile pic reminds me of an old senior programmer I worked under. I’d constantly be in trouble with him for spending too much time trying to understand the why and how instead of just slapping a quick fix and moving on….only for an issue to arise later. Such a terrible philosophy. The time and money overall wasted if you’d just put in the correct effort upfront instead of a hack that only exacerbates the issue worse down the line because you didn’t really solve the problem to begin with.
Point is, sure, if you don’t have time or the correct tools, just recap and swap/resocket all the chips, but that’s just a lame blanket response and would make a god awful video that would only make a certain senior programmer happy that I hope is no longer in the business. Just because it’s faster or efficient does not mean it’s the best solution.
Learning why a machine isn’t running is valuable and trying to see the problem confirms issues before you have to make drastic decisions like desoldering chips. We could have been dealing here with so many issues like bad traces even, so only chip swapping doesn’t teach anything.
As for the rust, it won’t do anything on the PCB so no real reason to remove it IMHO.
Yup, I think if you're a retro youtuber, it's best to go through the proper process to test and determine why things aren't working and show that process because a lot of viewers don't have multiple machines in every situation and it's good to learn the testing proces. However, If you're not doing it for a video and you have a spare machine to test on, of course you'll just do that from the start. As for the rust, I think Adrian still needs to run that motherboard through the dishwasher. :)
@@TechnicolorMammoth Just a comment on the quick fix vs investigating the problem in the workplace. I get both sides of it. Having done IT forever, I come from the time when you would sit and analyze an issue and work to understand, solve and hopefully document it. Nowadays with IT areas such as desktop, the practice is to reimage a machine, not to figure out what's wrong with it. The idea behind that is that rather than spending hours trying to figure out what went wrong with a machine, you can quickly reimage the machine and they'll be back working again. The issue with trying to fix the problem is that you may think you solved the issue and possibly didn't get all the issues of the problem and could cause multiple revisits and issues down the line. An example might be a computer infected with a virus, you don't really try to fix it, you wipe out the machine and start from scratch. Anyway, this doesn't apply to as much to hardware like adrians videos or even areas where you're both the user and the repair guy, but I can see how it is different in the workplace.
Ι use a special tip for the soldering iron and melted plastic from a ziplock to reattach the keyboard in such cases.Provided the customer is willing to pay a premium for the labour.
Yes, I like the style of how you track down the cause of an error. And your diagnostic thinking. ⌨️ That's why I like to watch your videos. 👍
Meanwhile I am watching this on a 5820k system I found in trash years ago. Motherboard was entirely covered with mud and lying bare with a heap of other electronic scrap and yet been extremely reliable and even came with 16 gigs of ram.
Some of my previous systems have similar stories...
It's always a pleasure to follow your enthusiastic investigations in these kinds of computosaurus 😉
What a fantastic video! I love watching you hunt out the problem. Looking forward to part 2!
Wow, that was amazing. That's one resilient old computer. This video also gives me something to work with on repairing my A500.
Thank you for the good videos . Next time start measuring the onboard power levels because I would not hesitate assuming most of the problems where related to the two capacitors.