Fixing a Commodore 1541 Disk Drive
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- čas přidán 3. 06. 2024
- Time to break out the the oscilloscope! It's time to fix a dead Commodore 1541 disk drive. This drive is a short board 1541 with an Alps Mechanism.
--- Video Links:
Lincoln Coast Road Trip where I got this 1541:
• Picking up an Amiga 10...
Finding a shorted tantalum capacitor:
• Fixing a PC that won't...
iz8dwf's Channel:
/ @iz8dwf
--- Tools
Deoxit D5:
amzn.to/2VvOKy1
store.caig.com/s.nl/it.A/id.16...
Jonard Tools EX-2 Chip Extractor:
amzn.to/2VazxDS
www.jonard.com/Products/EX-2-...
Wiha Chip Lifter:
amzn.to/3a9ftWw
www.wihatools.com/precision-c...
O-Ring Pick Set: (I use these to lift chips off boards)
amzn.to/3a9x54J
Elenco Electronics LP-560 Logic Probe:
amzn.to/2VrT5lW
Hakko FR301 Desoldering Iron:
amzn.to/2ye6xC0
Rigol DS1054Z Four Channel Oscilloscope:
www.rigolna.com/products/digi...
Head Worn Magnifying Goggles / Dual Lens Flip-In Head Magnifier:
amzn.to/3adRbuy
TL866II Plus Chip Tester and EPROM programmer: (The MiniPro)
amzn.to/2wG4tlP
www.aliexpress.com/item/33000...
TS100 Soldering Iron:
amzn.to/2K36dJ5
www.ebay.com/itm/TS100-65W-MI...
EEVBlog 121GW Multimeter:
www.eevblog.com/product/121gw/
DSLogic Basic Logic Analyzer:
amzn.to/2RDSDQw
www.ebay.com/itm/USB-Logic-DS...
Magnetic Screw Holder:
amzn.to/3b8LOhG
www.harborfreight.com/4-inch-...
Universal ZIP sockets: (clones, used on my ZIF-64 test machine)
www.ebay.com/itm/14-16-18-20-...
RetroTink 2X Upconverter: (to hook up something like a C64 to HDMI)
www.retrotink.com/
Plato (Clone) Side Cutters: (order five)
www.ebay.com/itm/1-2-5-10PCS-...
Heat Sinks:
www.aliexpress.com/item/32537...
Little squeezy bottles: (available elsewhere too)
amzn.to/3b8LOOI
--- Links
My GitHub repository:
github.com/misterblack1?tab=r...
Commodore Computer Club / Vancouver, WA - Portland, OR - PDX Commodore Users Group
www.commodorecomputerclub.com/
--- C64 Stuff
JaffyDOS:
blog.worldofjani.com/?p=3544
C64 Test Harness I use:
• Building a Commodore 6...
C64 Homebrew cartridge PCB: (used for the DeadTest / Diag Cart I use)
www.ebay.com/itm/Commodore-64...
EasyFlash 3 Multi-Cart:
store.go4retro.com/easyflash-3/
--- Instructional videos
My video on damage-free chip removal:
• How to remove chips wi...
--- Music
Intro music by:
Nathan Divino
@itsnathandivino
Outro Music:
Abyss by | e s c p | escp-music.bandcamp.com
Music promoted by www.free-stock-music.com
Attribution 4.0 International (CC BY 4.0)
creativecommons.org/licenses/... - Věda a technologie
Awesome to see that drive running!! Great work! I did all my most involved 1541 troubleshooting on it when I got it. I powered it on several times AND I tried 2 different disks! :-) Then I put it on the shelf. ;-) Considering where that stuff came from, I am impressed you are getting these running! Great work as always!!!
Attaching a C64 and querying the command channel (@ with FASTLOAD) is a diagnostic that I have not seen anybody consider. If it succeeds, it tells a lot: CPU, ROM, RAM, one of the two VIAs, and +5VDC are good. Then swapping the VIAs would be the very next step to see if the fault follows. (They are typically socketed.)
My mind is blown. I used to repair these things at a school board. I might of repaired 6 to 10 1541, c64s, 1701 a day. Very fast high volume repair shop. I can still hear the diagnostic audio test playing in my head. Thanks for the memories. Wow. I can't believe all the old hardware that didn't make it to landfill. Imagine a time where computers that never knew what a virus was.
4 years later this video is still valuable! That tidbit about the 74123 can interfere with reading disks might be what I needed to hear. Thanks Adrian!
You should have had a shot of you putting the chip in the bad chip box. It's tradition!
Big Car
I am so happy you’re around, to tell other people how to do things. We need supervision from leaders like you.
Thank you!
My first repair! When age 9 Mom got me one of those cheap 30 watt Radio Shack soldering irons and a roll of good ole lead solder. Went to use my C64 and the magic smoke came out off the 1541 , I opened it up and managed to break the fuse holder then find the problem, the bridge rectifier had a burned hole in it. So Mom took me back to RadioShack and bought a new bridge rectifier and a fuse holder. Working unsupervised age 9 I had the drive running by dinner! - That set my path! By 12 I had my Novice ham license and was searching for the next thing I could try to fix.
"If you're doing the drinking game, it's time to take another drink!"
Oh no guys! He figured us out!
ive had arians videos playing in the background... its now 3am local time and I cannot feel my face.
DeOxiT... slam!
Adrian, I subscribe to a few different channels that are informative. I learn from them all, including yours. One aspect of yours that stands out, however, is that you take time to take us viewers all the way through the process: your thinking, testing, failing, trying another angle, ultimately leading to success. To me, it feels like I'm there with you on what you're working on. It's a subtle thing, but it is really huge as well. Thank you!
@ Adrian's Digital Basement
I just noticed... You're currently at 64K subscribers. LOL!
As for the drinking game, probably not. I can't really get drunk. All I get is the hangover so it's kind of a no go. As for that jumper though. The Alps heads are wound a little more thereby having a few more joules to impart to the disk. If it writes to heavily, it can create hard bad blocks on the floppies. Considering how rare those are these days it could create some problems for you when you go to format a diskette you've used for something else in that drive. Total pain where you sit because then you have to low level format it and pray it works to clear the bad blocks, which it sometimes can (note to future selves for floppies that are otherwise trash). That said, I have a lot of love for old machines. Between you and Curious Mark I've learned a lot and even used it. There aren't words for how grateful I am for the knowledge. I've pulled 5 machines from storage and restored them because of you guys. Thanks man, and if you ever make it to Spokane I'd like to hang out for awhile so feel free to message me if that sounds like a plan to you too.
Another name I've heard of for those C-clips is "Jesus clips". So called because when they go flying across the room when taking them off, that's how you express your disdain.
Hehe ... exact same thing happened to me a couple of days ago ... was also going to make a video on it :) was looking at the same schematics ... you should have seen my wife’s face as I was running through the house with the disk drive and a trail of magic smoke behind me :)
Oh god i have a minor picture in my head, just with 2 doomguys. xD
I thought of you when the tantalum went bad. Hey that’s RetroSpector’s trick! ;-)
And therefore she gave you a new "THE C64" for birthday?! :-) :-)
I love watching your videos. Takes me back to my childhood with my c64 and 1541 which I still have in my closet. I need to get it out to show my kids a real computer.
This video was awesome! Specifically, in the "modern era" of PCs, who would have have thought you at to have a cpu running things like a disk drive! Today, disk (floppy) drives are all most forgotten about and redundant. Once again many thanks for an excellent video.
I had a dead 6502 in my original 1541 drive too. It was very easy to fault find as it got very VERY hot! I also replaced the MOS branded logic chips and electrolytic capacitors while it was apart. My drive had been extensively modded by a teenage me. I fitted an 80mm fan to the top of the lid (complete with holes melted through by a soldering iron) and also drive select toggle switches on the back with two red LEDs on the front to show the drive number. It's now hooked up to my PC via a ZoomFloppy.
Fantastic. I could watch you troubleshoot stuff all day.
8:40 "If you're doing the drinking game..."
Don't drink deoxit ;)
But they say antioxidants are good for you!
It might be opposite of detox. 😔
Who the heck would ever dislike videos like this. Seriously, you know what to expect before watching, and Adrian never disappoints.
Probably a Speccy user.
Great video Adrian. Nice camera work and editing. I used to work on electronic repairs for a school board. We had many hundreds Vic20/C64 and even Amigas. I enjoy the way you describe what you are doing while you are troubleshooting.
Back in the day I got a new C64 with a 1541, I new zero about computers. I bought a tape drive from a friend and was using that a while til one day he came over and was like, wth are you doing, using a tape drive, you have a disk drive! I had no clue what it was even for. LOL. Those were the days...
Head alignment is the most important aspect of 1541 repair. I’d love to see you do that. You already have the scope, you just need the analog alignment disk.
Bad sector copy protection played hell with 1541s because they would run over to track 0 and bang the heads against the stop when they hit a bad sector. I was an Atari guy but had coworkers with 64's. It cracked me up when the 1541 would suddenly step over and go "ack ack ack ack ack ack ...". Not nice on the old stepper motor mechanical head positioning systems.
finding those alignment disks is difficult. those who have them are hoarding them. 😁
@Mr Guru Cool, link for the disks? I haven't needed one myself because I've just aligned drives (like the trs-80) with a known good disk. Also, with the apple ii, the disk alignment stuff is pretty easy as well (stephen buggie has a video on youtube). I've never had any reason to do it with a c64 though.
@Mr Guru Yup. I don't have any alignment issues personally, but it would be handy to have a disk while they're still around. Though, honestly I wouldn't put much effort into fixing a drive since it's a dead medium and they aren't making more. Better off spending the money on a pi1541 or sd2iec.
Mr Guru As a former Commodore bench tech, I can tell you about 10% of 1541 repairs were due to head alignment issues. We would score and epoxy the stepper motor spindle after alignment to keep it there.
Awesome stuff!! Doing basic repair on 1541/1571 drives was how I got started as a kid fixing computers, and basic electronics in the late 80's, and usually it involved cleaning/lubing the drives, going to my local Radio Shack/Computer store for belts, replacing a cap, or sometimes simply on the lever drives just putting the pin back into place with some hot snot so it would not pop out again, and it would open/close proper. However the last drive I repaired was almost 25 years ago now, so honestly thanks for memories. 👍👍
Love repairing videos and how you explain the thought process! Thank you Adrian and keep up the great content!
Can't believe the 6502 was the problem! Nice work!
I love to watch a successful repair. Well done Adrian.
Love your work Adrian. Keep those videos coming!
Tants my nemesis! Used a lot in 70’s & 80’s audio equipment, sometimes used for their audio characteristics and low ESR, but used a lot just for their size. I must have changed more Tants "Just in case” than any other componant. Ive obviously canged more eletrolytics but they give away their faults in a more obvious way. Yes a dead tant is in you face but they go from good to bad in micro seconds rather than slowly over time like electrolytic’s. And if a piece of kit you’ve just worked on, goes pop, on a gig or in a studio sesion then say goodbye to your reputation !
I find your videos fascinating, the fault finding is great. Another good to go product!
I remember taking a hole puncher and cutting a notch in the other side of my 5-1/4" single-sided floppy disks to make them double-sided.
This is one of the best troubleshoot & repair videos I've seen on YT regardless of category. Nicely done. I've subscribed to your channel.
Wonderful restoration job on that 1541, I never get enough of seeing Commodore devices being brought back to life, those are the only computers I grew up knowing aside from the Apple II.
Another fantastic troubleshooting session ... love these!
great job of logically going through the troubleshooting process...you're a pro!
Good catch Adrian and a very explanatory video, thumbs up!
As a retired EE with 50 years of oscilloscope use I can say that I have had several scope probe ground clips fail. Other test leads as well. Right where the hard rubber for the strain relief ends is common. Grab both the metal ends and you may be able to pull the lead apart and see where the metal failed. It can be very frustrating figuring out what's going on, especially when its not completely broken, just intermittent.
The best video for fixing a 1541 online ! Thanks for taking the time to create and share this video !!
One day we'll get to hear Adrian say "Bringing out my ZIF 1514"
Can't help you with the scope probe. My 40 year old B&K 1465 came with it's original probes and the ground clips still work on that. Probably just the copper inside died.
It's not different than my TS100 soldering iron which recently had the power cable fail in a similar one. Both are soft silicone cables -- so maybe there is a bad manufacturer in China....
Man these videos take me back to my early computer days. My first machine was a C=128 and I ordered a 1571 and a dataset with the package from Sears (My only credit card!) Later I picked up an old c64 for personal use as I couldn't get access with 2 kids in high school using the 128 all the time. I even had a plus4 when the price on them dropped to 20 bucks. Even went so far as to buy a luggable from a fellow user who went to PC. I sold that several years ago for enough money to buy a new laptop. Now I sort of wish I still had it but there are many things in life that I feel that way about. Thanks for the trip back in time!
Thumbs Up! Excellent video. I think this is the first video where I have seen someone take apart the clamping mechanism. Very helpful. Thanks!
Love your repair vids, really informative! And I love your explanations.
Amazing video. Excellent production. Very knowledgeable. I love it!!!
Small correction and I’m sure you probably know but the reset vector on the 6502 is at 0xfffc not 0xffff. Great video.
Thanks Adrian for making such interesting vids about hardware I used to use in my teens
This video is very Serendipitous for me, as I'm digging out some old c64 disk drives to give them away, and I'm finding out that many are having the exact same issue. Thank You so much!
Impressive investigation and repair. I think you would make a fine forensic detective!
Great video. Although I am not very knowledgeable about electronics, I enjoy watching you fix computers and Commodore 1541. Keep up the excellent videos!
Thanks! You helped fix my drive. I had exactly the same symptoms as you did and walked through with you step by step with my oscilloscope, to discover, I too had a faulty 6502. My drive is now working!
When I worked in a school as a lab technician, I have seen this oscilloscope thing happen a few times, Agilent stuff.
I repaired mine by replacing the drive nechanism. When i was in poland over the summer, i got a drive locally (25 k) on a bike and brought it back to Canada in my luggage . It worked, and surprisingly it was an ALPS unit that wasn't shot. Rare. The german built replacement also had no screws in it!
I had multiple 1541 drives and all are Alps -- so I've had good luck with them being reliable. I must say a 1541 is a boat of a boat anchor so it's good your luggage didn't go overweight!
@@adriansdigitalbasement I was thinking of discarding the breadbox in Poland and just shipping the drive, but I brought almost nothing with me for vacation so I had lots of room. Even brought back a few PCs ;) Someone actually bought the 220v case off me, so that recouped some of my expenditure.
As for ALPS, the site I went to to get notes had mentioned that the ALPS units are pretty much unreliable. Good work again, I can see you're changing your tone in the vids, I'm thinking of doing the same ;)
Yes we sure do love your repair video's😁👍 Thanks!
had a pile of those in my shop. started scraping them out and they worked. Never knew anybody was interested in using them again.
Great seeing these deep dives with the scope.
Fixed one of these the other day where the motor wouldn't spin. Turned out to be a bad inverter which seems to be a common issue.
Great that you got this little guy working again. They really are workhorse drives. I have some that say in a Storage on Tucson For 18 years in the heat, and just requires a bit of cleaning and lube to be fully functional again.
Great repair. Fun to watch.
Great job Adrian.
I have plenty of experience about test leads and ground leads breaking. Frequent bends does that to even the highly flexible vires. What I have found useful in detecting the location of thew break is to have the meter on beep and then grab different short sections of the cable between fingers and push, sort of trying to shorten the wire. If I am at the break point, it typically makes contact as indicated by a beep.. It is easier to do with rubber or silicone insulated wires, because they are softer.
Often I can also detect an extra flexible spot, where the copper is broken. Maybe a light pull and bend reveals the break in those situations.. Then I just cut, apply silicone sleeving (or heat shrink, peel a short length of the ends, solder the wires and pull the sleeving on.
Considerably more cumbersome when the break is at the very end or even inside the molded strain relief. But that is another story.
Ground lead is easy to fix, just cut the plastic away from the copper plated steel spring, and solder a new wire onto it, then cover with some heatshrink sleeving. Use extra flexible cable, and you can make a slightly longer lead, though you will lose some signal integrity on the longer lead, but will make it more convenient to probe multiple places instead of the extra lead you added to the ground lead.
Great work. 💾
Thanks so much for sharing. 😎👌🏼
Great stuff, love seeing these 1541 refurbs. My red light of death issue lat year was the CPU being held in Reset. Turned out to be the UA1 IC. Thanks to @GadgetUK164 for pointing me in the right direction.
Congratulations on 64k subscribers. :)
11:00 Thank goodness that I'm not the only one who's metering equipment just decided to go on the fritz.
Took me back to my old C64 / 1541 combo. It was a big upgrade from an old Sinclair ZX81 as at the time it was the closest thing I could get that felt like a real computer and not a glorified calculator. Might have to have a rummage in the loft, never know it might still be up there from when I switched to an A1200. Love your detailed explanation of how it all is supposed to work, I got into an electronics repair job but at the time it was all transistors and valves as we were still using 1960s/70's RADAR technology at the time.
Thanks for another great video, I always enjoy watching them! Regarding the dead CPU, I do not know much about them but if a ROM/RAM was bad, would the CPU still show activity - while trying to access the ROM - or would it just try once and then give up?
Great video and very easy to understand...…………….hi from Tasmania. Australia...…...Cheers
YOU sir, ROCK! thank you for the tutorial/explanation/walk-through!!!!
Good job, Adrian.
Just bumped into your channel, this is good stuff.
Fancy meeting you here Phil! Adrian does some great videos for sure.
Welcome! This is a great place to learn how to fix old stuff, or just hang out with other like-minded people and have a nice chat.
@@gregfleury1705 I am in complete agreement with everything you said, but i would like to add that Adrian seems like a genuinely nice guy; e.g. i have never heard him utter a harsh word at anyone, at worst he may cuss at some recalcitrant piece of equipment ;)
I remember in my teens fixing my 1541. It was reporting I/O errors I guess as I had to change the two LMxxxx chips that make up the head amplifier. They were listed as VCR head amplifiers, but I guess one magnetic head is like another. Thanks for the video.
10:45 the ground wire is bad. Yes this has happened to me. Trust nothing! LOL When murphy's law can get you, it will.
Just loves your videos, to bad they are consumed so fast hehe more more :D you doing a great job, loving intro in real retro style.. keep up the good work, and real nice way of telling and showing how to handle retro check and repairs.
you are a great inspiration, i have reasonable electronic knowledge and just purchased a C64 with disk drive, no PSU and not knowing if any of it works...fingers crossed will be an interesting project
Love your videos! After no success with the pi1541 and the sd2iec troubles with fastloaders i'm extremely tempted by a real 1541
Hi Adrian, lots of fantastic information here! I was hoping you would get into drive alignment as well. Perhaps in a future video?
Greak job man ! Thx for saving a part of a great computer history. Mine runs with original DolphinDOS 3.0
1 minute, 6 likes already! Nice! :)
Nice fix! I really didn't think it would be that specific part that had failed, but hey, Murphy's law and all that.
By the way, did the RPM show any change after you stripped it down to clean & lube it? Was it closer, or was it still just that little bit under?
Hi, one trick that I use for the oscilloscope is to connect the ground connection from the test point on the lower right corner to the board ground with a jumper cable and remove the little wire that is always in the way!
Your videos are gold. I have 2 C64 along 2 drives who both act not normal at all. I'm learning so much on what to probe and what might be the top issues.
The one C64 is my very first computer, I got when I was 8 years old, 29 years ago. It means a lot to me.
The second I bought a year ago, just to be able to find what's wrong with mine, but sadly it has issues as well and this makes it all more complicated. I'm not willing to buy another set. :)
My dusty 80's memory recalls that I had the exact problem with the 6502 in my 1541 going bad and I had to order a MOS 6502 from Commodore for $20.00, popped it in and it was fixed. A HS friend of mine had to do the same thing a few months later. Red light stayed on and drive spinning both times. My theory was AC voltage surges.
I took apart my own 1541 out of curiosity. It works, but I never took it apart. The chip pins are extremely rusty, there's a lot of shoddy repair work. Might have to do some proper maintenance. Thanks for the video!
Not sure if you're aware while doing it, but your hands are really good actors!
I guessed the problem with one look at the board (aside from the jumper and the bad socket). Just looking at the CPU you could tell it did not match the rest of the board and had been recently transplanted. Still a great vid on 1541 repair thanks.
Love the videos. Keep up the good work!!
Great job Adrian!
Good work. Love the videos. Keep it up!
Congratulations on the repair. When I restore old gear with tantalums, I replace all of them because they tend to burn a little too often and when one has failed the rest are likely on the threshold. There are I think 12 undocumented opcodes in at least some versions of the 6502B that will stall the CPU so unless you're watching with an analyzer from /RESET going high it's possible to see what you're seeing here and still have a good CPU if the ROM is bad. In the 80s these opcodes were commonly called KIL or HCF (halt, catch fire).
The two camera angles work well, and if one start crashing you have backup! :)
#1 show on youtube!
Love your videos Adrian. and im learning how to trouble shoot the old commodore stuff i have :)
thanks for sharing
greetings from Denmark
Hi again, I also remember that my "toaster" drive (because the way it pops out the disk) the plastic rails for the eject broke, you have to be careful with those, do not pop it hard keep pressure to move slowly the latch, and I had replaced the rails with brass inserts to repair the drive eject mechanism.
Nice work! The ROMs are always the first thing I check (after voltages ofc), especially on longboards. One of the ROM chips are very close to the rectifiers and that is often bad. One of the few bad 6502's I found was actually also in a drive (SX64 internal).
Enjoying your videos. I like to repair electronic equipment, and would appreciate a video or two with more in depth use and explanation of the oscilloscope for fault finding. My knowledge on their use is pretty shallow but I really want to learn! Any help would be appreciated 👍
Murphy got you for a while with that ground lug, eh? Great video as always!
Great videos. Thanks.
Enjoyed watching this.
I've bought a couple drives with read errors which only needed lubricating and cleaning the head. Paid like a third for the 2 drives of what a single working drive was sold for. These ones that seem stuck on etc. can cost a bit more to fix when you have to source chips for it
Hey there. Love this video - it's extremely informative.
Working on a 1541 of my own and was wondering what you used to extract the chips? The clearances between them and their caps is awfully tight.
Thanks!
Very nice job Adrian! Thumb up! :)
Informative video! I am working on 3 1541s right now myself - swapping out a bad head on one after doing the continuity test.
QUESTION - What is that doodad on your parts bin, that switches between an Atari logo, Rick Astley, etc?
Interesting fault! I watch iz8dwf too! Great source of repair information :) That broken ground lead means you have put it to good use! :D
Great fix adrian! It was funny seeing 3 hands working at the same time due to the extra cam hehe.
Another awesome session Adrian. I need you standing behind me at my technician day job. LOL.