I have done a lot of tinkering with those IBM drives in the 1980's... The drive you show at 2:48 is the actual drive that was in those controllers and computers of the day to load the microcode. It was behind a door on the cabinet and was only supposed to be accessed by the Customer Engineer (a technician that usually was resident on site at important installations to quickly repair things). Note that this type of drive has no front bezel, it just hinges open to insert/remove the diskette. There is nothing like a door lock, just a bulky manually operated catch. Also no things like a disk activity LED. The "early drive" you show is actually from the later use of that diskette in data entry stations (where data that would normally be punched on cards was written on these floppies). Those were the first ones that had front bezels, LED, door locking etc. The stepper motor is very slow, like 50-70ms track to track access time. It is linked to the head movement via a Malthezer Cross, a linkage that locks the heads in place when the stepper motor is not energized (it transfers rotation in the direction motor->heads but blocks rotation of the heads when the motor is not energized). The step mechanism is VERY noisy! You would not hear it in a typical mainframe server room of course, but you certainly hear it when used at home (on the next floor, even). Compare to a teletype :-) The drive had a proprietary IBM interface connector with signals similar to the later Shugart standard, but indeed with 150ohm pullups. I made interface boards that converted from that standard to the Shugart standard, which mainly consisted of beefy TTL drivers to drive the pullups. In those days I had a TRS-80 model 1 and I used NEWDOS/80 2.0. It had sophisticated configuration of the drive parameters. You could arbitrarily set the number of cylinders, sides, sectors per track, steprate, and even "double step". So my interface board included a divide-by-two on the "step" signal, I configured "double step" in the operating system and set it to the slowest steprate so the double step was slow enough for the drive to keep up. I modified the floppy controller to have 500kHz mode (as opposed to the 250kHz used on 5.25" drives) and with all this I was able to use this drive in NEWDOS/80 as a standard drive, but with more capacity (the standard drives for that computer were 5.25" single sided single density 35 tracks!) I still have a couple of them in storage, 3 in a big cabinet with powersupply and 50pin ribbon cable. I intend to power it up sometime and use GreaseWeasle to read what is on them.

Between this and Adrian's video we have so much more information that is easily available now!

I spent far too much time shuffling 8" floppy drives in PDP-11s. Lots of Shugart floppy drives, they were built like a tank and very reliable at the time considering how we abused them.

Excellent! I love seeing more CDC floppies out and about. The 9406 is actually what I needed for the Centurion since it supports seek pulses as fast as 3ms, but the 9400 that I bought uses a different type of stepper mechanism and only supports seek pulses as fast as 10ms. We had to do a little microcode editing on the controller card to slow it down. But, I've spent so much time with my head buried in the 9400, I've never actually seen what the 9406 looked like. It's really fascinating how much the CDC/Mag Peripherals design changed in such a short time!

In IBM San José Engineering lab, we wrote the 8” diskettes for the 2835 microcode, in a modified 2841 File Control Unit, with the required floppy microcode on modified TROS tapes. We had a special 8” diskette attached to the 2841 frame, that had R/W capability. This is the way we tested microcode and sent patches for the 2835/2305 high speed drum facility (which was actually made up of many disk platters, with multiple heads for track on each platter, and no physical head movement.

Thank you! I was maybe 10 (1991) and my father took me to an auction at a local community college. There was a desk with a terminal built into it and I’ve had the shape and screen size burnt into my memory but could not for the life of me place it. I could never find any information about it. You showed an image of an IBM 3470 and that was it exactly! I even remember they had another system that was two bolted together that shared an 8 line display? Anyhow. Thanks again. I finally know the name of that amazing looking terminal I’ve lusted over for over 30 years!

You can also specify 77 tracks with the DOS FORMAT command by using the /T:77 parameter.

There were two more types of floppies: Hard sectored, which had a physical hole for EACH SECTOR in addition to the index. Soft sectored, with only one hole, the index as mentioned in the movie. (Personal knowledge, worked with both types).

8" drives were already on the way out when I got interested in computers, but my first system had one attached (originally for data interchange between clients' older systems and the computer). You don't look a given hose... especially when said horse comes with a one cubic meter crate full of 1.2 MB 8" disks and your allowance isn't enough to cover a box of 5"1/4 disks per month. So for a couple of years, I used this drive a lot. Still works, btw.

Magnetic Peripherals was later spun off from CDC, becoming Imprimis, and still being based in Oklahoma City. It eventually became part of Seagate who adopted CDC/Imprimis' practice of using the names of birds and predatory fish to name their storage products.

Haha - this brings back memories - I was a DEC service engineer in the mid 80's, some pdp11's I looked after had RX01/RX02 8 inch floppy drives and a few pdp8s did too. They made a lovely clunking noise! I seem to remember they used pre-formatted IBM disks, and I think they could be read on an MS-DOS system too.

This takes me back! Those good old days where sometimes stuff worked, sometimes it didn’t, and sometimes you used the wrong interface and the whole thing went up in smoke. Still there was something special about using things like my first computer, an 8086 I built from dumpster parts with a 256 color 8-bit VGA card, (or 6809s and HC11s used in very early car ECUs in classic GMs), not to mention the family C64 as a kid and the Atari console my brother had, or the TRS80 that sometimes saw action. Much more interactive time where you still had to do more than just turn it on to use it.

I love how we are complaining about faint coil noises in our graphics cards nowadays, and this thing simply sounds like a tractor is pulling up the driveway.

To make things worse, there had been some drives which used a binary addressing scheme on the DS jumpers to allow up to 16 drives. Those resistor packs are termination resistors that should only be present on the last drive (floppy cables can be LONG), that's why they are socketed. Great episode and for the first time I did not learn something new, but had a pleasant summary of things that drove people nuts 40 years ago already.

Lovely to see the Dolch making an appearance again, mine has had a two year sleep but I should really wake it up.

"How should we name this amazing achievement in data storage technology? Well, it's a disk, and it's floppy... floppy disk?" I love how scientists and engineers name stuff :D

This brings back memories of the late 80's for me . I spent many hours putting in circuit nodes for a Gen Rad bed of nails tester. We'd save all our work on 8 inch floppy's and then at some point we'd transfer the files to a DEC main frame via a 1200 baud modem. I remember when we needed a fresh floppy you'd have to see a "gate keeper" guy that would dole them out sparingly. By today's standard these we're overbuilt and made them very survivable , yes you'll still have to replace components that normally succumb to deterioration. Great video on a nostalgic subject. 👍

wow Our company had a lot of these large 8 inch floppy drives and they worked fairly well. The big thing was pre internet days to track down parts and information. Grrr. 😎 Thanks.

2:01 - A grey bearded nitpick here: HP-IB was standardized as IEEE-488 GP-IB which indeed saw quite widespread use, but mostly in instrumentation. A metrology lab I work with still uses it, and one of the more surprising uses was as peripheral bus for Commodore (then CBM) PET series of 6502-based microcomputers. One of such peripherals was their dual drive intelligent 5,25" floppy unit (it contained two 65xx processors in the role of microcontrollers, and communicated with the host using a very high level ASCII protocol.) Weird.

Ohh, this takes me back to early 1982, when I upgraded my build-from-scrap-parts apple-2 clone with an SVA ZVX4 8" floppy controller, to get some more capacity for cp/m. If I remember correctly, the drives I got used, where also CDC drives, ds/dd. I almost failed at figuring out how to set all the options and jumpers to get everything working - this was all new to me and I was just 17 :) 8" floppies quickly fell out of fashion at that time here in Germany. With the massive amounts of S-100 machines using 8" floppies in the US at that time, things where different in the US. In Germany, we never had a big user base of 8" drives, instead the whole home computing notion startet, when 5,25" where already taking over due to them being massively cheaper. Another proof how brilliant the internet is - I would have sold my kidney for this video at the time (which I had to do in the first place, to get the drives and the controller).

Actually, extremely happy in this crash lesson, because i haven't worked with these in eons and i'm gathering parts and bits to un-defunct an older computer i have.

All you never knew you'd like to know about 8 inch floppy drives, I've really enjoyed this, thanks so much!

That takes me back to the late 80s when we'd back up our AutoCAD drawings onto 5.25 floppy disks. Never had to deal with the 8" drives, but it was interesting learning about them.

I remember there were also floppy disks with many index holes, including two closer together that marked the primary index. These were used in early personal computers such as Altair.

Woot. Yay I’m in OKC. Glad some cool computer history from here found its way to you. :)

What a ride, thank you for documenting this !

Always love seeing Bob - Mr. Fancy Pants.

great episode!! i love the older complicated computer stuff .....brilliant job!

A Dolch! Loved that machine even though by the time you'd carried it all the way through the airport it felt like you were taking your anvil on a business trip.

Thanks for providing all the details on 8" floppies! I had one on a CompuPro many many years ago.

There's always such cool stuff on your channel. Things that I've wondered about in the back of my mind and often forgotten. Love these nostalgia trips and revisiting things. ❤❤

Thanks for shining some light on the 8 inch mysteries! I have gone through most of this myself too and got it roughly working on my PC - roughly because it seems not to be stable but maybe that is due to the media I am using, so thanks for pointing out the differences between the various media types.

Thank goodness I missed both 8 tracks and 8 inch floppies. At one point though I had a ton of 1.2 meg floppies. There was a time in history when that was the most economical archival storage format. I never had reliability problems, either.

This is the single most entertaining video I've watched on YT in years. As an old techie growing up 5.25FDDs, I'm so glad I found this channel!

Freaking amazing! Kudos for you!

Interesting exploration of the lowly floppy interface. I was messing around with some shugart drives on a true blue IBM PC 30 some years ago and encountered some of the same difficulties some I never overcame. More recently was working with some "newer" equipment running up against old problems that didn't just magically disappear with time concerning cable lengths and terminations.

Excellent video as always Marc and crew. When I worked on those first PCs in detail it drove me crazy how many shortcuts and kludges were involved in "designing" the architecture. Signal lines repurposed. Triple fault to quickly move from 286 mode to real mode. Extended memory, Expanded Memory. . The kludges were like layers of an onion.

Marc, There were also several types of 8-inch floppies that were hard sectored with multiple index holes punched in the media. Many Broadcast Character Generators and Graphic Still Frame Stores used this style of 8-inch floppy for many years.

I’m not even into computers and this is fascinating. 👍🏻

The long awaited sequel!

Oh man that sound at the end takes me back

Fascinating!

Computer archeology at its finest 😙👌

man, a Dolch PAC!!! you really have the best toys in business :D greetings from Brazil, Marc!

Well yes, we all needed to know this! 😜👍💪💡

Ahh, this brings back memories. I spent most of my early career working on and with CDC equipment. The CDC floppy was the first soft media drive I ever worked with. I had to write some drivers for it back in the dark ages.

Fantastic love your team

Great video. I Forgot about locking drive doors. But my eyes keeped locked at those 9 track tape drives under the table.

Back in the ‘80s, when working at HP, I wrote low-level code to recover data (written in an incompatible format) on 8” disks using a 9895. Good times 😊

Cool, love the shout-out to Adrian Black. 😉

Carl…, we do miss him 😢

Seeing the Dolch all in one reminds me of my days in Q.93x E1 Primary Rate ISDN and T-1 telecommunications testing, we invested big money during the mid 90's. We had probably half dozen of those machines for Layer 2 and Layer 3 for pre regulation and compatibility testing, brings back many happy memories of worldwide travel and test labs. 🙂

In late 1979 I started my design of a floppy disk controller for a new line of computer: at that time I worked for the most prominent European Company in the field of Information Technology, and the floppy was the only mass storage unit available when mass production started: hard disks and tapes came later on... When the design was completed, it could control 4 8 inch unit and 2 51/4 unit: these units were manufactured by another division of the company and had an interface which was very similar to the Shugart interface. I recall now that I was using the same kind of "twisted" cable for 5 1/4 units that was shown in the video, not only for the unit selection lines, but including the two "motor on " control lines... ( those that started the spindle motor...). The controller was able to handle many kind of media including the so called Double Density recording scheme ( or MFM = Modified Frequency Modulation) but the data format complied with an European Standard Ecma, which provided 256 bytes per sector in place of the 512 bytes, which was more efficient. In my case the maximum capacity was 1 M bytes instead of 1.2 M bytes of the 512 bytes/sector format. Basically one byte was made of 8 bit cell, each lasting 2 microsecond for a total 16 microsecond per byte at nominal spindle speed. The formatter ( the logic function that controlled read and write operations) was based on a NEC 765 chip, which was the most popular part at that time.. One complication of my design, was that the System Bus was 16 bits wide, and so, when reading, two bytes were stored into registers , before being transferred into the System ram using a dma operation. To keep the Central unit as simple as possible, in an attempt to cut down costs, there was no centralized dma but each controlled that needed dma operations for data transfer ( like disk and tape), had to implement its dma interface which was cumbersome and rather complex. As a result the price burden was shifted from the Central Unit to the peripheral controllers, a very very bad choice!! Other problems that affected my design, were troubles at the system level: randomly a dma access to the memory completed with time out errors, and later on I found out that the problem was due to reflections on signals, since the backplane was not properly terminated... Other critical area was the so called " Data Separator" which basically " separated" data transitions from auxiliary transitions, when reading data in MFM mode... My first attempt to use a state machine with an 8 mhz clock to "separate" data, was a failure, especially when reading a 8 inch diskette, which was more critical than a 5 1/4 diskette. Only a far more complicated approach, was successful: all the logic circuits were then squeezed into a gate array which I designed in Texas Instrument, Houston, in the late summer of 1981... And that's all folks!

It was nice to watch. Thumb!

I remember seeing these massive floppy drives still being used at a CIBC bank in the mid 2000s. First computer I had in the 90s had a 5" drive and a 3". very cool

I remember the 9825 well... I grew up in the age of 5.25"... when I first saw the 9825, I thought (just like you say) "finally... grown up's floppies". Sometime much later, in the 1990s I spent weeks trying to work out how to connect an old 8" drive to my PC.... If only I had had one of Antoine's little adaptor boards back then.

They don't make things like they used to - - and I am eternally thankful for that :) .

The OLIVETTI M3030 used two 8" Floppy Drives.

the peculiar thing about the PC floppy interface is that it was made so "simple" compared to the rest of the machine. It's super complicated to change any configuration on the 5150, 5160, and 5170 models and if the expansion cards don't match the IBM originals the machine won't work correctly. Then we also had to use two cables for MFM and RLL drives because the 50 pin connector didn't have enough pins and those drives have an army of jumpers because every controller behaved differently. And despite of all this, the machines are still not natively hardware compatible with any other computer IBM made.

I appreciated the quick excerpt into playing the original Donkey Kong haha. Also, very interesting to see how much more mechanical devices were compared to now. I guess we can attribute that decreases to solid state? That might be a stretch because there are probably numerous things that contributed to that reduction in mechanical components and miniaturization.

I used to have Zenith 8086 PCs way back and the FDC on those had capability for all 4 floppy disks, in 5.25" and 3.5" (720k only). It required 5.25" drives with capability to handle DS0-3 for drives A to D. You could only use 3.5" drives as A or B unless you fiddled with the pinouts.

Try Greaseweazle, it is open source / open hardware magneric flux reader for FD. No need for fdd controler- it is USB.

You folks may just have created the most authoritative 8" floppy drive video out there, thanks!

I never used 8" floppies, but I do recall an old Burroughs computer used for payroll in the institution where I worked that had them. Cool video.

Best Cable Ever!

Goodness me that win95 boot sound brings back some memories.

I was going to make some magnetic media jokes but it just goes over everyones’ heads.

Have you by any chance watched the 8" drive recovery videos by Usagi Electric?

Unexpected Adrian!

Love the header :-)

Al Shugart also founded Seagate - who is still around and dominant today. They also created SASI - Shugart Associates Systems Interface - which was stadardized and became SCSI used by Apple, Sun and many Minicomputer and Mainframe suppliers. It took the workload of managing the drive off of the main system and turned it into a "block transfer" device. This greatly simplified the drivers AND allowed the peripheral to change to tape, RAID or whatever on its own with the host not having to spin up yet another driver. Seagate was also the first to introduce optical connects between peripherals. As SCSI got faster and wider the connector and cabling became unwieldy. In came the low power laser with cheap fiber to carry the load. The prices dropped so dramatically that it drove down fiber networking. Its why you can have cheap mega-datacenters today. If there isn't a Shugart Prize, there should be. I wanted to also chime in - the floppy (flexible) media and format thereon was quite unique for different systems. Same physical "blank" could be soft sectored (one hole per revolution) that indicated the start of sector zero. For those you had to write the entire track. (Read/Modify/Write) Some were hard sectored - wherein every sector had its own hole and the hardware counted them to read/write the specific one. No need to read the whole track. Every company had its own track definition. An Apple disk had a different format then a Xerox or IBM. I think the most interesting variant was the Apple LISA floppy (remember Hard Drives (from Seagate) were just coming out when the LISA was introduced). The LISA floppy had two slots on oppsite sides. This allowed it to read in the first half of the rotation and write as the media spun around to the other half. No one else ever did this to my understanding as it made for a much more expensive drive but as the LISA was a virtual memory OS it was necessary. Hard drives changed it all of course. (A 5 MEGABYTE drive in 1983 cost $5000 and we wondered WHY anyone needed that much storage. Hell OS/2 followed by Windows NT shipped in a huge box with 56 floppies! ROM was hugely expensive until FLASH and even that was costly until the MP3 revolution and SmartPhones starting with the Qualcomm QPhone and Microsoft Windows CE Smartphone and Blackberry which predated all Apple by quite a while. )

Interesting that this got uploaded right as I started thinking about a 8" drive subsystem i'm gonna be building for my Altair 8800c down the line! I'm using a FDC+ so I have the luxury of just being able to use soft-sectored drives. (Whew)

I remember the first version of the Burroughs B 2900 mainframe used an 8" floppy inside the cabinet to load the microcode. After a couple of years it was reengineered to use 5.25" floppies, like all the rest of the world by that time. The firmware was created on Convergent Technologies (later bought by Burroughs) B20 systems. They had a disk format all their own.

I’m in 8 inch floppy heaven. Because, you know… the format is dead. But here, it will go on forever.

With this quality of sarcasm you could apply to be British. Love the Video.

Would be interesting if you can do a video on floppy-drive-interface tape drives some time. Info on how those worked seems to be some of the rarer info on floppy drive connections.

That Win98 startup sound at the end literally killed me.

That sudden moment of nostalgia when you see disk format "BBC B"!

Never saw 8" floppy stuff in real but looks like a lot of fun!☻

great job :) i still have a one brand new box of 8" disks :)

Well, having tinkered with this a few years ago, yep. The basic operation didn't change. Mostly the interface, though the key signals are the same. The actual sector formatting was totally different.The 26-sector disk you used is the single-sided, single-density CP/M format. Also note that a few of the later PC floppy controller chips no longer handed single-density, or FM recording. If you really want to get into it, try running 22DISK (you can find it...) as it can format, read and write to the CP/M format. DOS and Windows cannot, nor can LINUX. A variant used with double-sided, double-density 8" used 8, 1024-byte sectors. I have built my own adapters, even designed one to do the automatic reduced write current for the inner tracks > 40. Later 8", and all the 80-track PC drives did that automatically in the drive itself. Most of the single-sided 8" did NOT have that, though only a problem when writing or formatting. I personally have several 8" drives, recently refurbished a huge Siemens FDD-200-8, 8", double-sided. Next is to get a PerSCI 299 DOUBLE - 8', double-sided drive going. It had TWO 8" 'drives' in one full-height 8" size. THIS one is extremely RARE to find! The original Shugart 50-pin interface allowed the selection of FOUR drives per interface, this was reduced to only 2 with the 34-pin PC interface, and the dreaded 'twist' was to eliminate the need to manually set the drive ID. (Most drives came pre-jumper-selected for DS1. (Also, the motor-on signal as well.) I have been able to access 8" drives in LINUX as well through the PC floppy port...

i remember the 8" floppies.... crazy how tech changed

Cool, never heard of "Champ Kong" :)

I used NEC H03's with dual 8" drives. Circa 1980's I have always wondered about the wire twist :)

o0O (The sarcasm is strong with this one) ... but warranted

2:40 - On the top right you can see the venerable HC-.003/U crystal package! (Yes, I know it's a capacitor, I was just amused at the similarity of shape, and the novelty of a huge motor start cap on a storage device :D )

Ah yes, at 26:55 that's a Tandberg drive. I worked on many of those when I worked at CPT, they had a tendency to go out of alignment often due to how the seek motor was mounted. I cursed them often (I did lots of realignments in the day...). But I also worked on many of the CDC drives as well a they were used in the Vydec dedicated word processors. Fun times...

5.25" floppy drives came when someone became more honest about their 8"

"We're gonna bomb the enemy back to the Stone Age!" "Geez Lieutenant, that's a bit harsh. I'm uncomfortable with bombing them back to the days of 8" floppy drives... those things were hell."

In the mid 80s I used a Tektronix firmware development system for the 8051 processor. The Tektronix booted and stored data on 8 inch floppies. I can't recall what kind.

There were also “hard sector” drives with an index hole for each sector, not just once per revolution. The Pertec drives on the original Altair 8800 were that way.

The very first IBM PC I got my hands on had 180kB single-sided 5.25 floppies... the first thing users did was to upgrade to the 360kB DSSD drives. Somewhere in my junk I have both of those old SS drives... was going to make a floppy for my RatShak Model 1 and never got 'round to it. Of course, the *very* first PC's were cassette-based, just like my Model 1. Long live EDTASM!

when i saw the title my first thought was: Will this more about PC problems with HeadLoad vs 4drives-adressing or about the 500kBit/s-FM Signal: I was not disappointed.

Re: Capacity I used an Intel MDS development system around 1980-81 (for 8085 based product) with two FD-drives and am pretty sure the 8" FDs held 180kbyte SS and 360 kbyte DS ( I think the OS was CP/M or something very like it)

Apparently, to create the 5 1/4" 1.2MB high-density floppy standard, IBM did the simple thing and basically took the 8" drive format and shrunk it. That's why the drivers are so compatible - the 5 1/4" HD format is literally the 8" format shrunken down. With a few more tracks since they halved the track width of the existing 5 1/4" format. That's why the number of tracks doubled, the use of 500kHz etc all came from the 8" format. It's also why there is the 360k/1.2MB floppy incompatibility. Note that there is also the speed difference - the 8" drive ran at I think 360RPM, while the 5 1/4" ran at 300RPM, which let you squeeze more bits in.

Nice what would you suggest would i do with multiple pieces of 5. 25 floppy drive and a box of floppy disks or more written.happy new year

I used baby floppies back when I was a kid and we had an IBM PC XT with 80286 CPU and no HDD at all, with an amber monochrome monitor. It had two drives: A: for DOS and B: for software. Of course I used it for gaming (e.g. Sokoban, Prince of Persia, Test Drive or Alley Cat), but didn't have Donkey Kong. Oh, and I remember Dysan :) 3.5" floppies are too mainstream for me, but 8" are a completely different thing... I never saw one in person. I'm too young of a computer geek, it seems. Maybe at some hackerspace. Those paleontologists definitely have a cool lab! When I studied chemistry, we had to do with way worse, LOL. As for the drives... just look at them, all done on a perfboard! Interesting.

I remember when someone donated a S100 development system to our school in the early 80s; there was little chance of us ever getting it running, so a few of us nerds shared the spoils; I ended up with the Persci dual 8" disk drive (277 or 290, not sure which). Sadly very little remains of the drive except for some rather nice DC motor / gearboxes which operated the disk clamps.

I do have some 8" HP floppies. I did read out low-level "flux-timing" images of them, but HxC cannot decode the M2FM 30-sector format used.

I use to own a TRS 80 model 2 which also uses 8" floppies. 7:50 I just noticed Champrogramming, it caught my eye due to the colors of the logo which is the same as Champ Games by the same John Champeau (who makes some really impressive Atari 2600 games).