Fixing a Microscience HH-1060 RLL Hard Drive

I recently acquired a few old Microscience MFM and RLL hard drives. Most would spin up but, they all had different issues preventing them from working correctly. In this video I'm showing how I fixed a really common error with the Microscience HH-1060 and Microscience HH-1050 related to the AutoPark Locking Solenoid. This error causes the drive to never fully complete the power on sequence and preventing an otherwise good drive from working correctly..

[@chandrab]

I was a customer of Microscience back in the late 80s. The HH1060 was a fast drive for the day, I still have one or two of them. I got to know some of the guys at Microscience and they great. RIP Barry Waxman.

[@Hardwareasylum]

I always wanted to do an article on the company and see if I could interview some of the original members. The company did quite a bit to advance hard drive technology, at least from what I have seen, and they were one of the few not to be consumed by larger brands. On a related note, I'm working on a new 286 build and plan to revive another Microscience drive for the project.

[@chandrab]

@@Hardwareasylum Interviewing the old school drive guys would be really interesting. I always thought Microscience made a good drive and no idea why they went under. I think it maybe they didn't make the jump into 3.5 drives? It seems the guy you want to talk with is Peter Kevin Nagle, the CEO of Microscience (linkedin). I'd get to them soon because unfortunately folks of that era are dropping off. 😞 Happy to help if you need.

[@cdos9186]

That was an extremely enjoyable video to watch, glad I found it. You provided a lot of informative information that I am happy to know. Love these Microscience drives and really loved to see the internals of one. You really should make more hard drive repairs or analysis content as you know a lot I don’t.

[@Hardwareasylum]

I am glad you liked the video. I have a couple more Microscience drives to fix however I am out of working control boards so, I'll either have to figure out how to repair a board or find some more broken drives and hermit crab the components. As for more repair videos, I'm working on a few so keep an eye out for those.

[@RichardRaehal]

I have an MFM hard drive from an the first computer I ever used. It is a ComputerLand BC88. The drive recently started throwing seek errors. I have been watching videos to learn as much as possible to try and fix it. Luckily I backed it all up before the seek errors started.

[@Hardwareasylum]

there isn't any coming back from a seek error on these drives, that is usually a platter or controller issue but some of the other mechanical issues you can generally fix without too much trouble.. I always wanted a hard drive like that but it never happened. When I started building my own computers IDE was the norm and I never really looked back. Until now. I have a future build planned, twill be a 386/40 + this hard drive. I have a couple videos up on the project already and at least 3 more in post to complete the project.

[@peterderhalbemeter]

Thank you for documenting this repair! I got the same type of drive with an Atari Mega recently, and it has the same power up issue. I don't have a replacement solenoid, so I wonder whether the existing one is just stuck and can be unstuck somehow. Something I might try. Thanks for showing the exact process! Just some feedback on the intro scene: It was irritating that it cut out right before the error click would be heard. :P I'd have watched the full video and not skipped half of it, searching for a full spin up, if I'd known from the start that it addresses the exact error I was having. :)

[@peterderhalbemeter]

Success! When the drive was *powered down*, I gave some gentle taps with a hammer onto the front of the drive (remove the plastic front plate), just right of where the flat cable goes inside of the drive. That way, the shocks travel down the moving direction of the heads, so you won't risk a head crash. For a couple of power cycles, the solenoid opened successfully, but I also had it get stuck again when powered down for a bit. So not a reliable repair, your method is certainly more permanent. It'd be great to know the pins going to the solenoid on the cables, such that one could actuate it many times from an external power source, with the rest of the drive powered down. You don't happen to know which ones these are? :)

[@Hardwareasylum]

You are right about the intro. I really should have have left the error and then rolled into my intro. Sadly, the only way I can fix it is to upload a new version which wipes out all of the comments and likes I have already gotten. However, if it will lead to more watches then I might just make it happen. :) As for your question. If you get some light machine oil and drop it down the edge of the solenoid that might be enough to get it working. I've been meaning to try that on the one I removed but, haven't gotten around to it yet. Oh, and you'll want to remove the solenoid before making the repair just to keep excess oil from getting inside the drive.

[@Hardwareasylum]

@@peterderhalbemeter I did at one point but didn't write them down. Besides, the pads that are accessible from outside the drive are different depending on what board revision you have

[@peterderhalbemeter]

@@Hardwareasylum Thanks for the reply! Don't worry about reuploading, losing the views and comments is probably not worth it. Maybe just an idea for the next great repair video! :) My drive now reliably unlocks on second try if it was shut down for a couple minutes. I have cycled the drive couple times to exercise the solenoid. Using the footage from your video, I *think* I identified the two pins that go to the solenoid: When the drive is on its back, board facing up and front of the drive facing you, it's the two lowest / closest pins in the left row on the long connector on the right side. But applying 5V to them directly after pulling the connector had no effect. I didn't dare going higher in case I got the wrong pins, as I didn't want to zap anything. Maybe something to try once I got the data off (no idea how to go about that yet, as it's an Atari drive and my Atari knowledge is zero). Long story short, thanks to your video I got the drive working again! :) Thanks for sharing your insights and procedure!

[@peterderhalbemeter]

As an update after the drive had a chance to sit unpowered overnight: It sometimes takes about 5-6 attempts for the first successful head unlock. Power cycling rapidly (flick switch off and back on right away) after an unsuccessful unload hopefully limits the strain on the drive, though I'm sure it still is quite bad for the electronics. But I am able to read and use the drive perfectly once spun up, which is a great success! :) I'm currently trying to get the data off the drive using PARCP or maybe serial. Maybe afterwards I'll experiment more with getting the solenoid unstuck via the pins on the cable header. I was able to measure a short voltage spike on the two pins I mentioned when the drive tries to unload, so I might be on the right track. Thanks again for the video! :)

[@AiOinc1]

Wow! Where did you get so many drives? Always wish I could stumble across a treasure trove like this. Usually the closest I get is pulling WD Caviars from recycling yard machines. The HH-725 is a stepper drive, not servo actuated. They are totally open loop with no feedback. 1:53 They are called tantalum and they are pretty well known for failing dead short and starting fires like this. Hence the nickname "tantrum" capacitors. 2:26 The board on your left is a newer revision, it's made on a newer manufacturing process. You can see that the infill on the ground planes is more complete - This was not possible with the older plating process, which would make them bubble up and flake off with large surface areas. 3:47 if it's reporting all bad tracks then you are much more likely to have a failed head or head amp than actual platter damage. You would hear damage that severe. 7:53 This is called the ST-506 or ST-412 interface. They can signal in any encoding you want, the smaller 20 pin connector carries the differential data signals and the 34 pin connector carries control signals. These drives are "dumb" and will attempt to respond to essentially any command you give them. The primary difference between the 506 and 412 interfaces is that the 412 swaps a hardware reduce write current signal (something most later drives implemented internally without the need for a controller) for an extra head select signal. 9:18 This is a linear voice coil drive, which is different than the "modern" radial voice coil drive. The radial design shows up sometime in the late 80s, I think in Quantum's voice coil drives first, and sort of became the standard. Another similar design was the rotary voice coil - Used on the Rodime RO3000 series, Microscience 7000 series, Plus HardCard 20, etc. It was popular because it was "patent-free," even though the radial actuators have much better balance characteristics for faster seeking. 12:46 I wouldnt recommend using compressed air, the aerosol can sometimes come out as liquid and sit on top of the platters which can corrode them or damage the heads.

[@Hardwareasylum]

Hey there, glad you liked the video, and good job on the fact check, comments go a long way to get videos like this ranked. The drives were from ebay (pretty sure I mentioned that in the video). A few of the drives have the same head lock issue, some of the control boards have random errors and a handful of the drives work perfectly. The original plan was to fix up the drives and sell them off but, it would seem the demand for hardware of this generation is pretty low to non-existent. So, we shall see what happens to them in the future. Maybe they will become video props. Oh wait. I did a video about that already. :)

[@AiOinc1]

@@Hardwareasylum Interesting that they came from eBay, I'm a huge collector of vintage hard disk drives, and I've never seen so many appear in a lot at once. Shame that they're props! I would have loved to have a few myself. They are good stand in drives for a couple swap tricks, because of their high head count and auto parking. I recently bought a large box of IMI 5000H series drives from an industrial supplier in Texas with the intent to do a repair video like this, though I plan to keep (or donate) the drives afterwards.

[@Hardwareasylum]

​@@AiOinc1 Well, by prop I mean something like this kzbin.info/www/bejne/rnqupaCadtV6ZtU The drive was locked up so I salvaged some parts, fired up my 3D Printer and leveraged my PC modding skills. You can spot the drive in the background of some of my newer videos, hence the "prop" comment. The Microscience drives are extremely well made and I plan to use a few more from the stash in future projects. I might even try to track down the old company in Taiwan and see if they will do an interview. Doubtful but, I have some connections. As for finding some yourself, I already told you where to look, my alert goes off every month or so. :) they are out there.

[@NikolaiKostadinov-dc7jq]

Hello i have a Microscience hh-1050 with the same revision shown your video 33-307 however i do not have that wire that runs down in the ICs can you please show them so i can wire it? My drive isn't spinning up nothing is broken or shortened but i speculate it may have something to do with that wire