• Please review our updated Terms and Rules here

What is your favorite MFM drive make/model? What country made the most reliable drive

lowen said:
I'm having a difficult time determining a single 'favorite' since there have been a number of really good ones over the years. I can say that my least favorite was the whole Tandon TM50x/TM60x full height 5.25. You could cause a head crash by accidentally moving the fluid damper on the stepper motor, which was strategically (or maybe tragically) placed to where you couldn't help but bump it when removing or installing the drive....
Click to expand...

You'll get no argument from me on the FH Tandons. Horrible things. But then, it seems to me that Jugi was all about selling lots of cheap stuff. JTS, I think, represents the nadir of his game. I knew a couple of fellows who worked at Tandon's small "R&D" operation on Coleman Rd. in San Jose in the 80s. It was never clear to me what they did--mostly show up at 10 AM or thereabouts and leave by 4 PM with an hour and a half for lunch, it seemed.
 
Another one here for the early full height Rodimes, although I'm not too sure they were that reliable. I used to have plenty of 5MB RO201s and 10MB RO202s, from the pick of engineering returns in my first IT job. It was then just a case of matching working circuit boards with working drive mechanisms. IIRC the engineers used to repair the circuit boards using patch/update schematics supplied by Rodime (although I seam to remember the documentation (and the drives?) came from Scotland, not Ireland).

Only last year I hooked up a 10MB Rodime RO202 to a 486 PC and loaded up DOS 3.3. Boy was it slow, but fun for a while listening to the rhythmic soft thudding of the heads moving back n forth during file access. :)
 
Chuck(G) said:
I suppose one could point to a similar situation with the IBM 5170 and the 6MHz and 8MHz versions.
Click to expand...
What was the issue there? Wasn't the 8mhz version introduced later on? Or, is the issue that IBM added wait states in the 5170? Didn't both versions have wait states?
 
People realized that kicking the CPU speed up by replacing a crystal was a comparatively safe way to get more out of the box. I suspect that the 5170 was still in current production when Intel decided to discontinue the 6MHz speed grade of the 80286, so there was really no good reason not to replace the crystal.

I've heard various explanations by IBM for doing what they did next--add a clock check in the 6MHz 5170 BIOS. They all sounded pretty phony to me.

Back in the day, there were outfits who'd offer crystal kits of varying speed and even some PLL implementation that allowed for near-continuous variation of the CPU clock speed. Check the back pages of a contemporaneous PC Week and you'll see what I mean.
 
I guess it was true that they were afraid the AT would be too powerful and interfere with their mainframe business.
 
I was sort of under the impression it was for more nebulous reasons. Imagine a modified 5170 finding its way in to an important unusual business use, where by some odd chance the modification causes it to not work as advertised because it is operating outside of the published specifications. It may look like IBMs fault.

But who knows? Perhaps they signed some secret purchasing agreement with Intel agreeing to only run them at 6mhz in order to get a lower price (due to the 6mhz discontinuation) - and letting people get away with speeding it up might make them look like they were violating the contract. Something like that, they would not be able to tell people directly because it could upset other vendors buying intel chips.
 
offensive_Jerk said:
I guess it was true that they were afraid the AT would be too powerful and interfere with their mainframe business.
Click to expand...

I almost spewed my hot tea....

The AT was never even close to the power of the mainframes. The minicomputer side of the IBM house maybe, but contemporaneous System/370 models are orders of magnitude more powerful than the AT ever was. (Take, for instance, the mid-range 4381 Group 3 with 32MB of processor storage that was introduced in 1983; or, better yet, compare the S/370 model 158 from 1972 with an 8.6MHz clock and 4MB main storage).

They just weren't in the habit of letting people get free performance upgrades. Plus, many of the AT's that were overclocked had issues with other chips on the motherboard, mostly the ROM chips and the RAS/CAS delay logic, causing random errors. Quoting Scott Mueller's first edition of 'Upgrading and Repairing PC's' on page 80:
Many observers believed that [the model 239 ROM speed detect code] change was to prevent the AT from being "too fast" and therefore competing with IBM's minicomputers. This belief was untrue. Actually, the earlier motherboard was intentionally run at 6MHz because IBM did not believe that the ROM BIOS software and critical system timing was fully operational at higher speed.
Click to expand...

The PC AT Model 339 and 319 fixed the problems (should be faster ROM's and tighter, designed for 8MHz timing, specifically the RAS and CAS delay lines along with the RAM chips themselves).
 
For me? Simple, the MiniScribe 8450XT drive... still have a working one in my HeadStart computer and the sound of that thing is just awesome!! :) And when it reads/writes you can hear all kinds of clicks etc (already did that 27 years ago when it was new). Just loved the drive ever since I have that computer (since I was 12) and I hope it never dies on me (I know, I know... MiniScribe).
 
Oops! My mistake about the country of origin for Rodime drives. They were based in Scotland, not Ireland. I must have had St. Patrick's day on the brain.
 
Easy enough to confuse, both have bagpipes and Gaelic. :)

Seriously, though. Seagate is registered in Dublin, Ireland, although, as far as I know, there was a manufacturing plant at Clomel for only a fairly short time. Here's an interesting take on Seagate/Al Shugart back in the early days.

I remember when Al Shugart started up the 5.25" hard drive business back in the late 70s. He started out by calling the operation Shugart Technology and almost immediately was threatened by a lawsuit from Xerox, who had only recently acquired Shugart Associates. So the name was changed. I don't know if any drives escaped with the "Shugart Technology" name; if so, they'd be engineering samples.
 
Last edited:
Chuck(G) said:
Easy enough to confuse, both have bagpipes and Gaelic. :)

Seriously, though. Seagate is registered in Dublin, Ireland, although, as far as I know, there was a manufacturing plant at Clomel for only a fairly short time. Here's an interesting take on Seagate/Al Shugart back in the early days.

I remember when Al Shugart started up the 5.25" hard drive business back in the late 70s. He started out by calling the operation Shugart Technology and almost immediately was threatened by a lawsuit from Xerox, who had only recently acquired Shugart Associates. So the name was changed. I don't know if any drives escaped with the "Shugart Technology" name; if so, they'd be engineering samples.
Click to expand...



There were some Shugart hard drives that got into the market. I had one and used it for around five years. Shugart was not the first to market 5.25" hard drives, but his drives had slighter higher capacity than the completing drive and price. For instance, when the 5mb (formatted) full height drive was standard for many brands, the equivalent Shugart drive was 6mb (formatted). And when other hard drive manufacturers were building 10mb drives, as the next step up from the 5mb 5.25" full height drive, the Shugart drive was 11mb.

Shugart became Seagate before the next generation drives made it to market. The only Shugart 5.25 full height hard drives that I ever saw and used were the 6mb and 11mb drives.

Compupro was a early adopter of the Shugart 6mb 5.25" full height hard drive. I ran CDOS 3.1D on a Shugart 6mb hard drive for years before I switched to a CDC 80mb drive.
 
Were those drives "Shugart Technology" or "Shugart Associates"? Two different companies. And then there was "Shugart Venture"...

The only SA hard drives I own are an SA-4010 and an SA-1000. (14" and 8")
 
Chuck(G) said:
Were those drives "Shugart Technology" or "Shugart Associates"? Two different companies. And then there was "Shugart Venture"...

The only SA hard drives I own are an SA-4010 and an SA-1000. (14" and 8")
Click to expand...



It's been so long now that I can't remember. I may have picked them up when I attended one of a series of auctions held up in the Bay Area when the Shugart Facilities were being closed/consolidated after Al Shugart sold out, and Shugart's floppy drive manufacturing was being dismantled/discontinued in the U.S. by Xerox. I picked up one car load of logic boards for the SA-800/801, SA-810/860, and the SA-850/851 along with some partial floppy drives remains (mostly 8", probably were returns, rejects, and engineering samples, no new production line quality stuff). There was very little 1st grade/condition product, what I saw was mostly tooling, test equipment, and old junk. I couldn't touch what some Bidders were offering for the little bit of 1st grade product, and I was there mostly to see what I could find in the way of parts for my 8" floppy drive service business.

There were a few 5.25" Shugart hard drives (I had the chance to buy more at other auctions) at later dates.... The ones that I eventually ended up with were brand-new in the box.
 
You must log in or register to reply here.
Back
Top