This is how to use an 8" disk drive on the PC

This is the next installment of the TRS-80 Model II "Left for dead" series. In this video I get figure out how to get the 8" disk drive working so I can test it along with creating a disk from an image. This will allow boot the TRS-80 Model II once it is re-assembled.
Part 1: kzbin.info/www/bejne/rmmnl4adbNSAjck
Part 2: kzbin.info/www/bejne/h4LLe3aIh9CZetk
Part 3a: This video!
Part 3b: kzbin.info/www/bejne/iH6wYmmlmrl1bqM (all about termination)
Part 4: kzbin.info/www/bejne/bXXde6uajsmfgbM
Part 5: kzbin.info/www/bejne/Y5mUi3qurMemhsk
Part 6: kzbin.info/www/bejne/r360moNojdWgos0
Part 7: kzbin.info/www/bejne/Y5awnWWoaK98rpY
Companion video on disk termination:
kzbin.info/www/bejne/iH6wYmmlmrl1bqM
--- Video Links
IMD / Imagedisk:
dunfield.classiccmp.org/img/index.htm
Shugard SA800 Maintenance Manual:
www.bitsavers.org/pdf/shugart/SA8xx/39025-1_SA800_801_Service_Manual_Mar82.pdf
Disk Drive / Floppy Drives (Wikipedia)
en.wikipedia.org/wiki/Floppy_disk
TRS-80 Model II manuals:
electrickery.hosting.philpem.me.uk/comp/trs80m2/doc/
TRS-80 Model II Github Archive:
github.com/pski/model2archive
Ebay 50 pin to 34 pin adapter:
www.ebay.com/itm/114924378003
Adrian's Digital Basement ][ (Second Channel)
kzbin.info/door/btwi4wK1YXd9AyV_4UcE6g
Support the channel on Patreon:
www.patreon.com/adriansdigitalbasement
-- Tools
Deoxit D5:
amzn.to/2VvOKy1
store.caig.com/s.nl/it.A/id.1602/.f
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/digital-oscilloscopes/1000z/
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/33000308958.html
TS100 Soldering Iron:
amzn.to/2K36dJ5
www.ebay.com/itm/TS100-65W-MINI-Digital-OLED-Programmable-Soldering-Iron-Anti-static-Structure/113382669853
EEVBlog 121GW Multimeter:
www.eevblog.com/product/121gw/
DSLogic Basic Logic Analyzer:
amzn.to/2RDSDQw
www.ebay.com/itm/USB-Logic-DSLogic-Basic-Analyzer-16Ch-100MHz-4Ch-400MHz-Xilinx-Spartan-6-FPGA/202543965672
Magnetic Screw Holder:
amzn.to/3b8LOhG
www.harborfreight.com/4-inch-magnetic-parts-tray-90566.html
Universal ZIP sockets: (clones, used on my ZIF-64 test machine)
www.ebay.com/itm/14-16-18-20-24-28-32-40-pin-IC-Test-Universal-ZIF-Socket-Fs/303206721971
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-Micro-Scissor-125mm-PLATO-170-Electronics-Cutter-Side-Cutting-Pliers/163458746184
Heat Sinks:
www.aliexpress.com/item/32537183709.html
Little squeezy bottles: (available elsewhere too)
amzn.to/3b8LOOI
--- Links
My GitHub repository:
github.com/misterblack1?tab=repositories
Commodore Computer Club / Vancouver, WA - Portland, OR - PDX Commodore Users Group
www.commodorecomputerclub.com/
--- Instructional videos
My video on damage-free chip removal:
kzbin.info/www/bejne/joK5m6qGqLt5mpo
--- Music
Intro music and other tracks by:
Nathan Divino
@itsnathandivino

[@sysghost]

"So... which component draws the most power in your system?" Me: "The graphics card." Someone else: "The CPU" Adrian: "The disk drive."

[@senilyDeluxe]

CuriousMarc (screaming over the TTY noises): The KEYBOARD.

[@thebiggerbyte5991]

Everyone: 120 Watts?! Adrian: No, volts. :)

[@thesteelrodent1796]

pretty normal for disk drives to be the biggest power draw in PCs before 2000, although in the 80s and 90s it was the harddrives, not the floppy drives. You used to have to dimension the power supply around how many HDDs you had in the system. I remember my brother blew the power supply on his 286 because he added a 40 MB drive on top of the original 20 MB, because the PSU couldn't handle the extra draw on startup (old HDDs use a ton of power when starting up). Personally I've had even modern PSUs stall with HDDs from the 90s because the spindle motor draws so much power from stopped state, and it's worse once they've been allowed to sit for a while

[@Paxmax]

Heheee I put in a cooling fan into my 1540 (5n1/4) drive for my C64... And yeah, the psu of the drive was more or less similar in size to the C64 psu.

[@joeturner7959]

@@thesteelrodent1796 When my roommate would turn on his Xerox 820... all the lights would dim. All.

[@CuriousMarc]

Ah! That’s Antoine’s adapter, which he developed after we struggled to interface our 8” floppy in our “fossil data part 2” video. He sent me a couple too!

[@benjaminhanke79]

I expected that when I heared it was shipped from france.

[@adriansdigitalbasement]

Oh how awesome! And so very reasonably priced

[@theSoundCarddatabase]

I think we all got that adapter :)

[@ForgottenMachines]

I bought one as well, just one month before this video was published! So glad you guys did the preliminary work on this!

[@ForgottenMachines]

Interestingly, though, when I bought mine, I got it with the direct card-edge connector right on the board, which means that Adrian's custom cable would not be necessary...but still it's fun to see him make it right before our eyes!

[@LGR]

Oh wow. The moment at 29:29 had me grinning ear to ear, how awesome is that? Something I have always wanted to see happen through a DOS PC. The fact that big mess o' wires made that happen is simply wonderful. Great vid, Adrian!

[@adriansdigitalbasement]

Thanks Clint! I knew it technically should have worked, but I was so excited when it all _actually_ worked.

[@LGR]

@@adriansdigitalbasement Yes! It only got better later on once you worked out the settings, that's so wild to boot DOS from

[@VintageTechFan]

@@LGR Now it's your term. Hook one up to one of your PCs, get a big box of 8" disks, and install Duke Nukem from it.

[@StigDesign]

I Smiled Too :D

[@dylanlac765n6]

So Clint when are we seeing an LGR 8” floppy video lol

[@pastedtomato]

I don't know what is more impressive, the fact that 8 inch drives work on a regular PC, that the one out of the TRS worked, or that there's over 5 GB worth of software for the Model II

[@absalomdraconis]

You want to know something really out there? Not only were standard floppy controllers compatible with (some speeds/densities of) all three common floppy drives, but they also supported some tape drives with the same pins.

[@pastedtomato]

@@absalomdraconis Holy cow that's true! Found the Colorado Jumbo 350 and Conner 51250 N

[@ZXRulezzz]

@@pastedtomato All kinds of QIC tape drives with floppy connection were common in the early 90's. But those were a pain in the a** though. Computer usually couldn't do anything else while it was working with tape, both in DOS and Windows. As far as I remember, Windows actually came to a halt while the drive was working, with brief moments of responsiveness between reads. And data density was kinda low, unless there's a "hardware compression" card installed in your machine, installed between the actual floppy cable and the tape drive.

[@Doug_in_NC]

Back in the late 80’s I used an electron microscope at my university with some sort of custom computer running it. It was pretty much an antique at the time, and had a pair of 8” drives with the OS and software on them. The interesting thing is that you could see exactly why 8” drives are the size they are - two of them fit perfectly side by side into a standard 19” rack, just like the ones your average 1960s or 70’s mainframe / mini computer was built into.

[@3dartstudio007]

I've got one of those double disk drives for rack mount. It came on a CNC machine from the 80's for a wire EDM machine. Didn't know if these old drives were ever going to be worth anything to collectors again.

[@drewgehringer7813]

an 8 inch disk is also about as wide across as the U.S. standard 8.5 inch x 11 inch paper format, so 8-inch disks fit in sleeves that could be used in standard document binders

[@Doug_in_NC]

@@3dartstudio007 It looks like any outdated computer equipment more than about 20 years old begins to increase in value again. Time to start hoarding DVD drives, I guess

[@dycedargselderbrother5353]

@@Doug_in_NC I've wondered if Lightscribe would ever become retro. It wasn't super popular at the time but I have a feeling it'll eventually be branded as "That's so 2000s!" and end up more popular as a nostalgic collector item than it was as a living format.

[@bobvines00]

Yeah, I've got three sets of RX01s & RX02s for my PDP-8s & VT-78, so you're correct about them fitting the 19-inch racks. I've also got a dual stack of 8-inch drives (RX-01s, I think) that are one-wide in a very narrow tower, I guess to better fit into an office, given that the top has a wood pattern veneer/plastic on the top & edges.

[@billholloway9175]

Adrian. I ran the cobra bbs up here in brantford Ontario Canada. I had model 1 running newdos 80 v2. I bought 4 8 inch drives at a surplus store in Toronto. I got it to work using newdos 80 pdrive command. I paid 10 bucks each for the drives. Got cables and blank disks with it. Printers were so expensive back then I bought 4 model 33 teletypes. Had a friend who made an interface and ran it through the cassette port. It was a site to see coming back on a scooter with them tied dangleing over the back and front wheels on the qew. Those where good days.

[@meep.472]

woah, thats cool. is it still possible to connect today with like a telnet client or something?

[@billholloway9175]

No. I bought a case of blank disks from the surplus store. Well the disks formatted fine but they use to crash during the day while I was at work. I would come home from work and using superutityplus and super zap to fix the message disk. It was the disks. This took me 6 hours sometimes. A single parent I had other things to do. Expensive for me for fidonet mail as well and the other phone line. It got to be just too much. When the internet came around the calls more or less stopped.

[@BenderdickCumbersnatch]

That's a great story, Bill! Have you seen BBS: The Documentary by Jason Scott? He has released it free on KZbin these days. It is incredibly good.

[@billholloway9175]

I will look for it. Did you run a bbs. Mine was called the cobra bbs. I ran the French connection I worked at a press shop so was usually tired when I got home but I worked on the bbs all the time. Model 33 teletype was my printer. No lowercase. Rolls of addition machine paper recorded logins and commands. Re-inked my printer with stamp pad ink. That was messy. It took me months to finally find out it was the disk. Even new good disks wouldn’t last a month. After a month I’d look at the message disk and you’d see where the message file. The 5 and quarter inch drives where cheap and pressure on the diskette took its toll on even the good disk.

[@leglessinoz]

@@billholloway9175 I ran a Fidonet BBS for quite a few years.

[@jkeelsnc]

Impressive. And this work is actually quite important to keep the history and legacy of these old computers going. I am glad someone is working on things like this.

[@raven4k998]

the real question is not can you do it the real question is why on earth would you want to put yourself through the trauma of doing that

[@jkeelsnc]

@@raven4k998 why do people completely restore old classic cars of all kinds? It’s a labor of love and interest. Also, it is an important historic preservation.

[@raven4k998]

@@jkeelsnc oh you want a labour of love find a bmw i3s totalled in a junk yard and restore it to road worthiness I dare you do it for bragging rights cause I am pretty sure you would be the first to do that one since no one cares about electric cars unless they are teslas

[@jeremiefaucher-goulet3365]

I was never woried. curiousmarc also got an 8" drive working with a Pentium-II computer in one of his videos, to retrieve old archeological data from disks made on a IBM/360. He too was using IMD if I remember correctly, but he had a harder difficulty in supporting the old IBM/360 disk format.

[@Graham-ce2yk]

That was indeed the case. The problem they had was that they were not sure which of the early formats the disks used. As it turned out it was the oldest format available one which emulated the data format used on punch cards, the system that the floppy disks replaced.

[@jeremiefaucher-goulet3365]

@@Graham-ce2yk Yes... Fascinating how a disk format/geometry was so wasteful in terms of disk storage, in order to be backward compatible with punch card equipment. I love this stuff!!

[@adberco]

It turns out that this adapter that I sell on eBay originates from the floppy disk adventure I had with curiousmarc, so we're closing the youtube connection loop here! :)

[@jeremiefaucher-goulet3365]

@@adberco Oh wow.... LE Antoine des vidéos avec Marc? En effet, le monde est petit 😁. Superbe ta collection de vieux microchips 👍. Et merci pour tes contributions pour sauvegarder la préhistoire de l'informatique!!

[@Graham-ce2yk]

@@jeremiefaucher-goulet3365 It all goes back to the IBM1401s which were designed to slot into the existing punch card based data architecture and replace several of the machines used in that architecture. As a result it's data structure and the structure used on magnetic tapes had to be easily translatable back into punch cards. The full transition away from punch cards was not complete by the time the first portable magnetic media (8-inch floppies) appeared and so their data structure, at least at first needed to be compatible with punch cards. Of course I have heard that even the latest IBM mainframe type computers can still emulate all previous architectures right back to the 1401....

[@shadowtheimpure]

"Ruined the cable" Nah, that's a good old-fashioned mod.

[@Dave5281968]

An it's not like you can't get ribbon cable. Even if the cable had been messed up you could replace it from DigiKey or Mouser. And, the new connector went on perfect just like if the factory had put it there in the first place.

[@michaelterrell]

I use a small drill press vise to install those connectors.

[@tim1724]

You're correct that the Apple II can write 140k on a 5.25" disk.The entry in the table shown in the video is labeled as "pre-DOS 3.3". If you had scrolled down a few lines you would have reached the second entry for the Disk ][, listing the 16-sector (140 KB) format used by DOS 3.3 (as well as Apple Pascal and ProDOS). Apple's DOS 3.1 (the first version they shipped to the public) as well as 3.2 and 3.2.1 used a 35 track, 13 sector format (256 byte sectors) for a total of 113.75 KB per single-sided disk. It used a 5-and-3 GCR encoding due to limitations in the original Disk ][ controller card that couldn't handle more than one consecutive zero bit in the data stream being read from the disk. The revised version the controller card that came a few years later allowed up to two consecutive zero bits, enabling DOS 3.3 (and all later Apple operating systems) to use 6-and-2 encoding to squeeze more sectors per track. Thus DOS 3.3, Apple Pascal, SOS (on the Apple ///), and ProDOS (which re-used the SOS filesystem) can fit 140 KB on a single-sided 5.25" disk.

[@nemesis2264]

It amazes me that the US Air Force were until fairly recently still using 8" floppy drives as part of the SACCS system that controls nuclear missiles. Part of the reason is that the old systems were supposedly unhackable and it was only really due to aging hardware and the associated maintenance issues that a replacement system needed to be found.

[@233kosta]

Can't be hacked if you're not connected to anything ;)

[@MichaelEhling]

"Adrian's Digital Archeology." Fascinating. Even through it was nearly an hour long, I found myself hoping for more.

[@Dee_Just_Dee]

18:10 Oh wow, this brings back memories for me. About 17 years ago I had a college electronics project that involved building a bespoke PCB that connected to a PC's LPT port. The professor had us buy 25-lead ribbon cables and clamp the connectors onto them ourselves. Yeah, the electronics lab PCs were older machines running Windows 98, so direct interfacing with the LPT port was still possible, and everything could still be done through QuickBasic, rather than using a more modern, higher-level language and interfacing over USB instead. It was pretty cool knowing that the bits I was setting to the LPT port were going straight to the board without any intermediaries, and through a cable that I had cobbled together myself.

[@the_kombinator]

Sounds like the stuff I did in the early 2000s at Centennial College ;)

[@standardnerd9840]

In 1990 I was a manager at Software Etc and our registers still use 8" floppies. We had to close out each day on the register, get out a giant disk mailer envelope and mail each day's disk to corporate. I couldn't believe we were still using those at a computer store. 🤣

[@l337pwnage]

Tricking people into "upgrading" product every year or so works mostly on consumers, not so much on businesses.

[@rnb250]

Wow!!

[@gr2238]

I remember those 8 inch drives. Used to service them in the pre IBM PC days. Two main problems. On the single side drive the head load solenoid would come out of adjustment and put pressure on the head and wear a track in the disk. They would also come out of alignment fairly often, needed a special disk and scope to align the drive. Great memories.

[@NuGanjaTron]

That's exactly what I had to do with my Altos drives (also SA800's). Quite a learning curve, but I got there eventually. Of course I couldn't find replacement pads, so it's all still a bit iffy.

[@carlcamp2979]

@@NuGanjaTron OMG Somebody that worked or used Altos Computers! By any chance was it the Altos 68000? Always wondered what the command prompt response for them was when it did not understand a basic program command stood for other than the obvious? It would say "WTF?" I was told once what the official answers was, but we always assumed the obvious default for that acronym.

[@SarahJaeckel]

8'' drives? OMG, down the memory lane. When I started in the graphic industry around 1990, I had the pleasure to work with a Berthold TPS 6300. Berthold was a German manufacturer of typesetting machines, technology leader back in the days. They closed in 1993 due to Apple and a bunch of own faults, not to mention arrogance on an epic level. Anyhow, so I got the chair in front of the tps and started to work with this green monitor landscape and especially this enormous keyboard. Honestly, this thing had the dimensions of a Yamaha DX-7. But after all these years, I still miss the multicode system: it had the capability to program on the fly whatever sequence desired into one of 4 "multicode" banks that repeated their content on touch. A fantastic tool in typesetting back then. Ah ok sorry, 8'' drives: this thing had two of them - one for the OS, the other for the work, pretty straightforward for a machine of these days. Only downside: starting the programming (yes, typesetting was much more of programming then dtp as we know it now), one had to define the target drive name. Once forgotten, the work was just saved into nirvana. Anyhow, every three months or so a guy from Berthold came along and recalibrated these two drives. He made a pretty good show then, slided the drives out of the machine, connected his oscilloscope (or at least pretended so), and worked quite a while on it. Which was pretty expensive. One day I had a closer look, a nice smile inclusive. And figured that the oscilloscope was not connected at all. So he explained to me what he was actually doing: he fixed the mechanism with a screwdriver, following his hearing. There was a certain "clack" desired, one screw to screw until clack, that's it. Needless to mention that we never called him again. For me, it was my entry into computer hardware. Still thankful for that.

[@olepigeon]

20:11 - I have the correct 3M crimp tool with several dies for different connectors, and actually a bench vice is WAY easier. The crimp tool is huge, steel, really heavy and unwieldy, and the dies are held on with plastic clips that break way too easily if (when) they snag on your clothes as you attempt to crimp. Furthermore, it's almost impossible to get a cable to crimp nice and even with the tool without a 2nd person. Bench vice is simply a better crimp tool.

[@WarhavenSC]

Bench vise also doubles as a warning to all the _other_ dice that might be thinking about rolling badly next game session.

[@nickwallette6201]

I got a cheap crimp tool off eBay that accommodates floppy, IDE, and SCSI cables just fine. There’s a plastic cartridge that slides in to a mount, and if you turn it upside down, it can do 5.25” edge connectors as well. IMO, it’s easier than a vice - which I’ve also used. I have a few dozen retro machines banging around and, with a roll of 3M cable and some Wurth or Sullins connectors from Digikey, I make custom length drive cables for all of them. :-)

[@user-gi1vg4ck1p]

Actually, using vice needs some practice too. I have no special tool, and didn't want to buy it for a one-time operation. Well, only after 4th or 5th try get a working connector. The connectors are usually fully plastic, which breaks too easily. And my vice produce uneven pressure even on the 34pin connector length, which only adds more problems. Interesting idea here to use slot covers on the vice, should try it if I will ever do that again.

[@Brian-L]

I’ve used a bench vice to crimp these connectors too. Worked perfect every time!

[@foogod4237]

_(Pardon me for a moment, have to go find a phone booth to put on my "Captain Pedantic" outfit... There! I'm back.)_ Just a minor note (because I noticed this both in the video and here): A bad habit/indulgence or illegal activity is a "vice" (with a C). The tool which holds things in place or presses things together is a "vise" (with an S)...

[@douro20]

This shows just how reliable these drives can be.

[@nickwallette6201]

That and the bits can be seen from space, so they have to drift quite a bit to fail.

[@davidsuzukiispolpot]

In 1983/1984, my friends and I embarked on a project to port CP/M to the TRS-80 Model 1. We got a bunch of surplus 8" drives and the way I got the controller to work was by modifying the clock circuit for the disk controller chip so that it would double the clock rate when talking to the 8" drives. That was likely also why professional computers would use 8"; the data rate was double. We had almost 2MB on the TRS-80 disks 8" (double density) and my friend really tweaked the sectors, format and interleave so it was FAST! You typed ws and the filename, and within less than a second you were editing the file. Much faster than the PCs of the time. Of course the controller we had didn't have a data rate setting, it was fixed by the input clock. It was the controller in the expansion box. The double-density adapters also worked with the doubled clock which is how we got the capacity and speed. I never created any cases, so the computer system would take up an entire desk, including the bare monitor. Luckily the cat never got electrocuted walking behind the screen.

[@stopthephilosophicalzombie9017]

Congratulations. As a kid of the 70's, disk drive noises still make chills run up my spine.

[@mogwaay]

Damn, Adrian spins such a good yarn, this content is just marvelous, thanks so much for taking the time to make these. I managed to get a PC 3.5" to work on my ZX Spectrum +2A which with the correct adapter expects the 3" Amstrad drives that the +3 and CPC6128 used and the Shugart SA800 manual was at the top of my list of references to make it work as the old 3" drives followed the Shugart spec closer than the modern PC drives do and I wanted to simulate the READY (RDY) signal. It blew my mind that apart from a few computers, almost all floppies are compatible with each other, including the waky 3" ones. So it is awesome to see a 8" drive using the same signalling to work just fine - great work!

[@bionicgeekgrrl]

Probably a case of why reinvent the wheel occurred

[@LordRenegrade]

People keep on talking about the unreliability of 5.25 drives, but I never really had a problem with any floppies that were stored properly and weren't of the "bulk discount" variety. Ditto for 3.5s, with the special warning that the disks AOL sent everybody (even in Canada) WERE definitely of the bulk discount variety.

[@williammentink]

I've only rarely had problems with 5.25 diskettes, just a lost sector here and there. However, for me at least, 3.5 diskettes have been very unreliable having had most of them fail. Of course, the 5.25 diskettes I made sure to only write on them using the same drives they were formatted on. The 3.5 were used in many different machines. That is something I learned in the seventies to protect your media, only write to the disk on the drive it was formatted on. The reads don't matter excepting that they density aren't downwardly compatible. Didn't have that option when I was forced to move to 3.5 sized diskettes.

[@nate6386]

The disks made in the 80s and early 90s that were not bargain bin disks still work to this day but the disks at the end of the 3.5" drive lifespan were all bargain bin disks and almost every one I bought or acquired in the late 90s or early 2000s are all dead now. I was working in IT at the time and had to keep a stack of windows XP disk controller drivers for installing windows XP before I discovered slipstreaming drivers into OS images.

[@LordRenegrade]

@@nate6386 - Yeah, the ones at the very end were definitely super-discount junk. Fortunately the vast majority of mine were bought before '95.

[@LordRenegrade]

@@williammentink - Different drives do indeed have different write qualities...and alignments. Plus the 5.25 HD drives (at least the PC variety ones) have narrower heads and write really narrow tracks (being 80 vs 40 tracks), so it's perfectly understandable that a DD drive might have some issues on DD disks formatted/written to by an HD drive (especially if it's alignment isn't perfectly identical). Most of my 5.25 experience was with this single 1571, so I didn't have to worry about the different drives having different characteristics or alignment ;) My first PC had a 5.25 HD drive, but it got little use as it also had 3.5 HD. Some of those 3.5 HD drives (or perhaps, MANY) are pretty miserable affairs though. Especially in later years.

[@user-gi1vg4ck1p]

What other people said about floppy *disks* is totally correct. Latest made 3.5in disks are crap. They were still sold new in our country till the early 2010s and by that time you can have several disks with bad blocks straight from newly opened pack! Older disks, if you can find them, are usually much better. Fortunately I have developed a rather consistent method to "fix" disks with a low number of bad blocks - format them to *lower* capacity (720K), then format back to stated 1.44M and bad blocks gone! I actually tried it otherwise with 5.25" disks - formatted 360K disk with almost half of it in bad blocks to 1.2M (yea, there would be lots of "errors", ignore them) and back to 360K again and it worked perfectly too. But it was the only experiment, as I have no other bad 360K disks ;) I 'm too young to see 5.25in disks actively used, so I may be wrong here, but I agree that 5.25in disks looks more reliable indeed. I was given several unopened boxes of them, which are slightly older than me (and I'm 36 y.o.), and all the disks were in perfect condition! But the problems could be with the drives: I have two Epson 5.25in drives, which both are failing to read anything consistently (moving parts operates fine, looks like it's an electronic issue), thought three other Teac drives work perfectly with the same disks. A 3.5in drives aren't a problem - there are still loads of them to send into trash bin and replace if needed.

[@MegaManNeo]

I know dealing with old technology such as these gigantic floppy diskettes isn't everyone's cup of tea (to be fair, those people wouldn't watch your channel either) but the fact that you can still hook these things up to more modern up to recent machines and use them is just as amazing as to think about just how much memory technology itself progressed in those past decades. We went from storage media bigger than a plate to such that can fit on your finger nails and hold a much much much bigger amount of data. To me as a kid of the 90's that experienced multiple generations of hardware on fast forward basically, this is amazing to behold.

[@BryanHamon]

I'm so happy you do this kind of stuff and the lengths you go to for testing! There is no other way I would think any of it is possible.

[@adgarza]

You always find a way to amaze me, Adrian. Never in my life I saw these kind of drives working, and more in a PC. This was a really impressive experiment. Congratulations for your patience and tenacity to achieve the targeted results.

[@GarthBeagle]

What an incredible test setup - very creative, especially since it worked!

[@ovalwingnut]

Your "Mad Scientist" designation is assured. I APPROVED THIS VIDEO.

[@kalensus]

Adrian, you have the gift in turning what I was expecting to be a mundane topic into something truly fascinating!

[@macdaddyns]

Done with the tenacity of a true retro geek, loved this video, can't wait for the reveal, I worked on a model 2 in 1983 for a professor when I was in grade 10. Admittedly can't remember much about the OS, but wrote some basic for him to control the tracking of a telescope. Keep up the great work!

[@jakubpolomsky]

I love the video! Anytime you show this kind of technology (be it this drive, or apple IIs, c64, ...) I immediately have to get myself my own (usually broken) unit so that I can try repairing it on my own and so far I was successful! You taught me the ways of debugging and patience for this old tech. Thank you for that Adrian!

[@Duddie82]

I worked for a company in the 1980s, and I have made backups on the smaller disk. I really enjoyed watching this video. I remember an older guy at our office told me about the large disks. I just never saw one of them ever. I really enjoyed watching this video!! Looking forward to more videos!!

[@Eremon1]

If it wasn't for minds like this gent's, we wouldn't have 3/4 of the things we have today. There's something comforting about knowing there is still folks out there that appreciate old tech.

[@necro_ware]

One of the greatest videos you made Adrian. Really, really cool! I enjoyed every minute.

[@willynebula6193]

I found your channel recently and have been binge watching all your videos. Tbh i think your channel is simply one of the best ive found! Thanks to you and your videos ive repaired 1x486 motherboard 2xVLB cards and 3x isa video cards!!! I always thought they had bad chips but appon very careful inspection all had broken pcb traces. I never could just chuck them out and now im over joyed that ive got them working again. Thank you.

[@Strykenine]

Sure looks like 8 inches to me. *Walks away*

[@user-lx3th5on8l]

HEY COME BACK DON'T LEAVE MEEEEEEEEE screams Mr floppy drive

😬​@@user-lx3th5on8l

[@Dave5281968]

An awesome job creating a boot disk for your model 2! I am on the edge of my seat looking forward to more of the TRS-80 Model II restoration!

[@mopedman666]

I’ve been researching how to do this for a while. Thank you for doing all the leg work.

[@ESDI80]

Very neat to see this! I used IMD to write floppies for my Kaypro. What was interesting is that the article on how to write the images for the Kaypro talks about modifying a 1.2 MB HD floppy drive to run at 300 RPM vs 360. 360KB DD drives run at 300 RPM and yielded perfect boot and program disks for my Kaypro.

[@adriansdigitalbasement]

Yeah that's right -- I have a 1.2mb drive that has a jumper to enable dual speed. WIth that set, when you use 250kbit with it, it runs at 300rpm and you get a 80 track double density drive, yielding 720k per double density disk. There were retro machines that used this format 96TPI vs 48TPI... I have a couple of those drives.

[@Renville80]

What you need to get or build, Adrian, for those times when you have to power AC equipment that you aren’t sure might short out is a “dim bulb” tester that has an incandescent bulb in series with the hot wire, so if it’s a dead short, the light illuminates brightly, but lights dimly when the current draw is more normal.

[@GrowlyBear917]

I put an incandescent bulb in series with the hot wire going to a compact fluorescent lamp (CFL). When the CFL failed years later, I had full brightness on the other bulb. Apparently when a CFL's life is ended, it shorts out and blows a fusible link inside its own ballast. But with my light bulb in series, the fusible link never burned. The things you learn just by experimenting!!

[@kjtroj]

Good to see the Model II work continuing. It'll be interesting to see what all that machine needs to get it up and running. Creative work on getting the drive tested

[@Iordlangford]

I share your passion for this form factor, never held one but allways thought the 8 inch format was insane and awesome.

[@abx42]

This reminds me of the old days when PCI wasn't a thing yet and I think you scared the drive into submission since it stopped making noise after you said you're going to take it apart

[@retrozmachine1189]

The TRS-80 MII used a WD FDC. It's not as easy to run as the 765 used in the PC but with that lack of ease comes more flexibility. On the 765 you more or less say 'format track with these parameters', then feed it the sector addresses as demanded. Whilst you can tinker with the inter sector gaps etc, there are limits. On the WD series FDCs the computer determines exactly what is written. Want a 43 byte ISG? No problem, just send 43 x 'N' during the track write. The WD is flexible enough to let one easily format a track half FM and half MFM. MI / MIII games would sometimes come on hybrid disks like this permitting the same disc to be booted in a MI or MIII

[@8bitwiz_]

Mixed density tracks weren't quite that easy. IIRC, the Model I did double density by using an I/O port address to switch between the original FDC chip and the double-density FDC chip in the upgrade board. Mixed density tracks on a Model I were done by literally switching FDC chips during the track write. It didn't have to be accurate, all it needed was a T0S0 recorded in each density for the boot sector.

[@edgardovigo147]

Man I love disk drive reading noises, brings memories. Amazing job Adrian thank you for share this.

[@itzcaseykc]

That is awesome being able to get those disk drives to work and the discs viable ones. I came across an 8" floppy years ago and still have it somewhere in my things.

[@edmclaughlin4923]

Adrian, one of your best videos. Don't understand the thumbs down on this one.

[@brentboswell1294]

Adrian: as I recall with 8" floppies, hard sector sizes were very common. There are holes in the central timing area to mark the sectors (instead of one hole on the whole disk, as was common for 5.25" drives). When you ordered 8" floppies, you had to be careful to order the correct number of hard sectors for the system 😉

[@greggv8]

There were also hard sectored 5.25" disks. I've seen one of those disks but never any computer that used them.

[@migry]

@@greggv8 Many years ago I managed to score some "Lanier" hard sectored 5&1/4 inch floppies from work. They worked perfectly in the Atari 800 1050 drive, which doesn't care about the index marker, so ignored all the extra index pulses from the index holes near the centre part of the disk. I suspect that they probably wouldn't have worked in many other systems where the index pulse was used.

[@chucku00]

Early compatible Logabax PCs Persona 1600 ( AKA Olivetti M24 and AT&T 6300) used hard sectored 5 1/4'' disks

[@nickwallette6201]

I accidentally bought a box of hard sectored 5.25” disks. If you put one in a DOS PC, the drive stays on for a while trying to find the second sector, but it keeps getting reset back to the index position before it’s able to read more than 1/9th of the track. Eventually it will time out and throw an error. Anybody need some hard sectored disks? :-P

[@8bitwiz_]

Back in the day, in the TRS-80 user group, sometimes people would bulk-buy floppy disks because the price was so much lower than what you could get retail, and sell the disks to others in the group. One time the guy ended up with hard-sectored disks. I didn't notice until I started to format one. Instead of the usual click... click... click... it went rat-a-tat-a-tat like some kind of machine gun.

[@davidben-ami9212]

Amazing work of restoring to life such ancient equipment and media!!!

[@chrishutton1458]

This is lovely. This is obviously your forte! It was a delight to view!

[@pipschannel1222]

Impressive! 👍 Very cool to see those huge old disks in action, especially in MS-DOS! You may already be aware of this but when you're going to refoam the dreaded Key Tronic keyboard: Kevin from Texelec has an excellent rebuild kit for these with homemade pads that frigging work ;-) I used these to rebuild a few of my Compaqs and while it's a tedious job: They work very well!

[@olepigeon]

My favorite obscure floppy format was the Tabor 3 1/4" floppy ''drivette.'' Yes, 3.25", not 3.5". It looked like the 8" and 5.25" disks, but was only 3.25 inches big. It's ... cute. :)

[@LordRenegrade]

This intrigues me and I wish to learn more. I'm off to google!

[@nickwallette6201]

I’m fond of the Nintendo Famicom Disk System disks. They were 3” disks, with the drive manufactured by Mitsumi. They were stripped down to the barest of minimalism. The head isn’t on a servo, it is mechanically driven by the spindle motor and some exotic gearing. The entire disk is read linearly from start to finish. You can stop and start, but once started you’re committed to follow through the rest of the pass, then the head resets itself (mechanically) to prepare for the next time. The head itself is more like an audio tape head than a floppy drive head. Single sided of course. And the vendor locking mechanism involves the shape of the logo pressed into the disk shell. Quirky as it gets!

[@button-puncher]

Thanks for the awesome video Adrian. I learned so much about older floppy drives. AMAZED to see a modern-ish PC use it to boot.

[@DaveGagliardi]

What an amazing video. Your troubleshooting skills are a joy to follow along with. Thank you for making this content, it contains everything I love about electronics and technology in a professional format that I would expect to see in an expensively produced TV show.

[@pineapplebob06]

One word to describe that drive “BEEFY!”

[@WooShell]

Many years ago I pulled a Y-E Data YD-180 from an Olivetti 80186 machine, including a passive adapter from Shugart 50pin to PC 34pin edge connector. It appears to work as a regular 1.2MB HD drive. So, there might never have been an 8" drive in a real IBM PC, but there definitely were some in IBM clones. It also requires a separate power supply, with the motor and the door locking solenoid running on 24V DC (thankfully not line AC, though..) Also, none of my 8" disks look "shiny", so I guess the reason why those drives have a head lift-off solenoid is because the Teflon easy-glide surface on the disks wasn't invented yet ;-)

[@leandrotami]

Fantastic job! I can't imagine how many hours of reading and also trial and error you devoted to this project. I have one single 8 inch floppy but I have never even seen an 8-inch drive in real life. I look forward to more videos about this!!

[@markedone9778]

I love these longer videos, please keep doing them. so informative and interesting.

[@Nighthawke70]

Some 8" disks will have issues with the liner wearing thin in the sleeve, causing the disk to seize up. The motor is so massive, it'll power right through the disk, making a huge mess in the drive!

[@letthetunesflow]

Btw, maybe use a sharpie to draw a line on the rotating motor, and then just use your video camera to film it rotating. You can then use the camera to see how many frames it takes to rotate one rotation. Using a high speed setting on your camera will give you an even more accurate estimate of speed! Just then do the math by using the cameras frame rate and count the number of frames it takes to make one rotation, then multiply that number with the speed of the camera. Just a thought, you may want try this to see if the motor is roughly running at the correct speed. I’d love to see a comparison between that method and using a device designed to test the rotation speed accurately! Thoughts on this method anyone? I’d love to hear what people think of trying this method! Cheers, love the channel Adrian!!!

[@hjalfi]

You've got to be careful with this --- some video cameras (like cell phone cameras) actually record at a variable frame rate, where the time per frame varies based on the light level. It makes cell phone video really awkward to edit as many editors assume a constant frame rate and as a result the audio and video never syncs up!

[@letthetunesflow]

@@hjalfi good point! I was thinking he would use the high speed on his studio cameras as they tend to be locked frame rates. But thanks for pointing out the issues with using a camera with variable frame rate! Cheers!

[@dparks256]

Loved this video - fascinating! Didn’t mind the length at all. Seeing all the steps is super informative and entertaining.

[@carlwillows]

Great video. Was very impressed to see you boot from that drive!

[@peewhocantbeaimed6954]

Back to having a Wang with 8 inches jokes...

[@shannoncurtis6660]

Yes you can, I've done it with windows ME.

[@armctec3531]

One of the best videos I've watched about 8' floppy, keep up the great work!! Thanks Adrian!!!

[@andydelle4509]

Somebody did make an ISA card for 8in FDDs. I work in the TV broadcast industry and in the early 80s much of our primitive computer based gear shared files on 8in floppys. We had an 8in drive connected to a PC to edit files on the 8in disk. It was an ISA card in the PC and the drive had a small case with it's own power supply for the drive. I don't remember any other interface hardware in the box, the drive connector just went to a 50pin telephone connector through a cable to the PC card. Good luck finding one but they did exist. It may have just been a standard floppy controller chip with a different connector but sold at a much higher price since it was a niche product.

[@muttBunch]

I still have a single big ass 8” from Maxell. I’m never parting with it.

[@the_kombinator]

I lost my (IIRC?) Sony 8 inch diskette...

[@Walczyk]

I use 8" drives exclusively, sick of losing data with cheap 3.5" floppies. Sure they are harder to set up, but I prefer the reliability over the speed

[@the_kombinator]

@@Walczyk Wat? I've got DD 720k diskettes from the 80s that were drilled out and formatted to 1.44Mb, and then back down to 720K and used for weekly backups (at least that's what the labels on them say). I had these diskettes for over 25 years with Windows 3.0 on them, which I use 2-3 times a year to install on retro machines. No faults over all this time. I think in the last 5 years, I threw out more moldy 3.5s than ones that became unusable for reasons other than a bad diskette drive. You must also be the guy who swears by 90s Maxtor drives :P

[@sinjhguddu4974]

My! That was thrilling! Kudos to those guys who never discard anything! And thanks for this inspiring job.

[@exidy-yt]

This is the sketchiest collection of bodged-cables i've ever seen. I am proud of you, sir. This is old-fashioned hardware hacking and I love it.

[@hammondeggsmusic]

No tachometer? You could record the sound and measure the period of the repeating waveform… can even take the time of more cycles and divide the time that by the number of cycles for some more precision…

[@coctailrob]

I had the same idea. I want to try this sometime. I wonder if driving the live output through a multimeter set to Hz mode would work for real-time calibration purposes. (Edit: probably too slow a frequency)

[@brentboswell1294]

You should be able to get a waveform from the factory timing hole optics of the drive...(assuming that soft sector disks are being used)

[@derek20la]

2:50 A full service manual. Good luck getting anything like that today. Shows how much the right to repair your own equipment has fallen.

[@metatechnologist]

Companies don't want you engineering better "clones". I was already thinking it wouldn't be too hard to manufacture this units. Outside the cast metal bits but even then not impossible...

[@desmur36]

This content was the best! Thank you for this - such a treat! Can’t wait for more Model II content!

[@Mediateritorist]

Adrian, it's sooo amazing to look your videos and enjoy your enthusiasm for your work... in each of your videos. 1 hour of video is like a mixture of crime-and adventure-movie and so entertaining... Thank you so much!!! Georg

[@revelationnow]

Only time I've seen 8" disks used was on an Australian destroyer (warship) back in about 1996. Their reasoning for using such out dated technology at the time was that they could salvage data from disks recovered from the bottom of the ocean, so there must be some credibility to their durability. Great video Adrian! Love seeing retro drives brought back to life.

[@bcostin]

This was a lot of fun. The sort of "Huh, seems like this oughta work...let's see!" spirit that makes technology fun.

[@LMacNeill]

Oh man. When I was a kid in the '70s and early '80s, my Dad had a Wang 2200 minicomputer that used 8" floppy disks. He had several that had games on them, and when he used to take me to the office with him, I knew exactly where he kept the disks with games on them, and I'd go load them up and entertain myself while he worked. :-) Been a *LONG* time since I've used 8" floppies in any capacity, though.

[@turtlebro4498]

This is pretty awesome, growing up in the 90s, at my elementary we got to use the 5-1/2" and i thought that was pretty awesome. its been so weird and fun passing through each storage medium from the 5-1/2" floppy disk to the 3-1/2" Floppy disk to the CD to the USB to the SD card to de Micro SD card and now the cloud storage. i never would have though this possible. i got my own PC (not a family one but one that was all mine) in 2001 and i was so happy cuz it had 256mb of ram and a 40 gb hard drive, now im sad if it has less than 16GB of ram and less than 3TB of storage. Time really does fly and i am happy to see videos of people working on keeping the history alive. Awesome work

[@johnmarchington3146]

Well done, Adrian. Another brilliant video.

[@stoojinator]

When that drive started up the first time, my grin was about as big as when my first child was born. That was an amazing video! I think it's awesome that these old beasties get a second life. When I was at school in around d1984, we had two PCs that had these big 8 inch drives. Both were mounted vertically. I honestly don't remember what they were as I never used it. We were lucky enough to use either Acorn or BBC Micros.

[@_Synthesize_Me_]

Thank you for finally making the video that I’ve always wished someone would make!

[@ItsYaBoi-ATA]

I know nothing about this topic and still found this interesting enough to watch the whole video, good job

[@Cpt_Adama]

Back in the 80's I was one of the youngest Radio Shack "Computer Marketing Representatives" and I use to sell these (Model II) to local business. Brings back memories, so cool.

[@ricke573]

Back in the early 1980s some of the IBM development labs attached 8-inch drives to 5150s (later, 5160s) because it was much more convenient to use a PC (or XT) as a disk writing station. Some of the prior disk writing stations used "interesting" S/370 control units that increased the work effort.

[@Zeem4]

Excellent work! Reminds me of the time I made an adapter cable to connect a 3" drive to a PC running FreeDOS, so I could read and write disk images of Amstrad PCW software.

[@dog61]

I used to work on this stuff back in the day. Great video. The crimping with the vice thing is pretty cool, too.

[@Toby_Q]

Awesome video. Amazing work with these old drives. Thanks for the content!

[@considerlizards]

This was..actually wholesome. An honest adventure. Subbed!

[@HeavyD6600]

Excellent video, Adrian! Thanks for sharing!

[@Raintiger88]

Totally awesome walk down memory lane. Thank you very much

[@Billy_G_Oat]

I only understood half of everything you talked about, but I enjoyed watching. I grew up in the late 70's and early 80's using a TRS-80 Model III and a TI-99/4a, both of which used a 5 1/4".

[@NaoPb]

Thanks for the video. Very nice that the 8" disk drives are working now!!

[@theblunderbussbrothers9547]

I wish I could have seen this video 8 years ago! I had a fascination with this old tech when I was in my early teens and I managed to get as far as formatting the disk on a Tandon TM-848E, but I never ran across the info for the proper format, and gave up after so many tries. I had to crimp my own 50-pin to 34-pin cable too, but elected to use a 34-pin cable split up and aligned properly for a partial crimp under the 50-pin SCSI connector. I also had one of those beefy Shugart 850 drives, but the mains voltage operation worried me a bit. Great stuff.

[@railwaymaniac]

This was a great watch! - So many memories. I still have a Shugart SA800 drive in the basement. 😎

[@erinwiebe7026]

Love these explore videos! It freakin' works!

[@UpLateGeek]

I love how getting this old hardware working is part gruelling research and part intuition. Aside from the actual repair and refurbishing of the hardware itself. It really doesn't help when resources on the Internet provide conflicting information, which is where the intuition part comes in. But it's good to see this working again. I'm sure someone embarking on their own repair and restoration project will find this a useful resource!

[@highpath4776]

I cannot recall what model word processor we had, I think someone bodged it to a unix terminal to a DEC PDP system as well ! I think the main software was Wordstar or New Word.

[@eramires]

Beautiful work man, so good to see these things, so many memories flash into my mind watching this xD

[@ChairmanMeow1]

I just adore the insane amount of wires poking every which way :D

[@greggsatlauttamus9743]

That was so fun to watch while heading home from work

[@dylanlac765n6]

finally KZbin recommendations brought me to the right place! Awesome video

[@VicTheVicar]

This is over the moon in coolness! Please do more 8" stuff - even if it's just random tricks.

[@poivre22]

Fantastic work, Adrian!

[@pauldourish]

Tremendous. Congratulations. Can’t wait to see the next steps!