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Anyone remember these HP "manual" disks?



#5

Anyone remember these manual 3.5" disks? I don't think they stuck around very long. I've been trying to locate some of these and now have approximately 20 such disks. Don't need them for any special reason, just adding to the pile.

These 3.5" disks had to be opened manualy, as the drive didn't do it for you. Then, to close the shutter, you had to squeeze the corner of the disk. The photo below shows how this works.

Click image for more details


Edited: 15 May 2006, 7:23 p.m.


#6

Hi Mike,

yes, I remember these disks very well,

those were delivered with software packs

for the HP-150 and 110...

Fortunately they changed the mechanism;-)

Regards

Raymond

#7

I wonder why they have "AUTO SHUTTER" printed on them 8)

(it might very well be, that those were really cheap ones, I experienced a similar "feature" on a lot of NoName-branded disks back in the 80s...)


#8

Quote:
(it might very well be, that those were really cheap ones, I experienced a similar "feature" on a lot of NoName-branded disks back in the 80s...)
I doubt they were cheaper, than the ones to follow. However, the drives were probably much cheaper, as they didn't have to have the opening mechanism, that was in the later drives.

Click image to zoom


Edited: 16 May 2006, 2:00 a.m.

#9

Quote:
I wonder why they have "AUTO SHUTTER" printed on them 8)

(it might very well be, that those were really cheap ones, I experienced a similar "feature" on a lot of NoName-branded disks back in the 80s...)


Because they 'shut' automatically when you press them!

#10

Absolutely. I missed them when they were new (back in the early 80s I was mainly using 5.25 floppies). So it was only recently that I got a bunch with
an HP-87. At first I thought they were ordinary diskettes, so I
simply put them in my 9121 and they worked fine. However, sometime later I realized that some of them had their shutters stuck open. I thought they were broken (smth wrong with the spring inside), so as I was fiddling with one, the shutter released and snapped back. Looking at the mechanism closer I realised what was happening, and soon I found some HP documentation that describes how to use them.

**vp

#11

Those things were a supremely BAD idea. What could the designer possibly have been thinking... or smoking...


#12

You say:

"Those things were a supremely BAD idea. What could the designer possibly have been thinking... or smoking... "

My reply:

How so? The only thing to compare against was a 5.25", whos only diskett cover (protection) was a paper cover. The cover was simply to protect the disc when not in the drive. It was the logical next step in the evolution of the disc. It was simply an integrated cover for the disc.

I don't think this was a "bad" idea. I just think the next evolution was a "better" idea.


Edited: 17 May 2006, 10:23 a.m.


#13

They had shutter, They had a spring. Why the heck did they not make the darn thing open and close automatically? I just can't figure out the mindset of the engineers and marketing people what would think a manual shutter was a good idea. Apparently neither could the rest of the known universe. When was the last time you saw a manual shutter disk drive.

It was almost as bad an idea as CDROM drives that required disk caddies.


#14

Quote:
They had shutter, They had a spring.
But they didn't have a drive to open the shutter. All drives before these didn't have any shutter to deal with, at all.

Hindsight is 20-20.

I'm surprised that they didn't have a 3.5" disc that didn't have a shutter at all (or did they?). Or, one that was completely manual, requiring manual movement to open and close it. The use of the word "automatic", seems to reflect an innovation (or change) from a non-automatic version.

PS: I think I've located another unopened box of 10 of these.


Edited: 17 May 2006, 10:47 a.m.


#15

Quote:
I'm surprised that they didn't have a 3.5" disc that didn't have a shutter at all (or did they?).

No; as far as I know, the shutter was a feature of every 3.5" disk design.

Quote:
Or, one that was completely manual, requiring manual movement to open and close it.

Whereas, the first version of the 3.5" was just like this.

Quote:
The use of the word "automatic", seems to reflect an innovation (or change) from a non-automatic version.

Exactly.

The very first Sony/HP 3.5" disks had a metal shutter that the user slid open by hand, and slid closed by hand. There was no mechanism at all inside the first drives to slide the shutter back and forth, since the disks that these replaced in the market were the 5.25" drives which only had sleeves to protect the recording surface of the disk, and any kind of shutter was a big improvement.

However, you can't insert a 5.25" disk into its drive without removing the sleeve, so no-one forgot to do that. But the shutter on the 3.5" disk is a part of it, and enough people got occasionally frustrated with the disks when they forgot to open the shutter first. Consequently, making the shutter open and close automatically was a natural incremental improvement, especially when it became apparent that the 3.5" drive was going to be in the market for a long time. But this improvement required the drive to have a new mechanism internally to engage with the shutter, which introduced a physical compatibility problem with earlier drives, and it would have been commercially stupid to introduce an incompatible design, so this compromise design appeared.

These semi-automatic disks were the engineering solution that smoothed over the transition, since they worked in the newer drives (which didn't push the shutter all the way open, so they could close by themselves upon being ejected), while being manually lockable in the open position for the older drives. This is why, on a manually-opened automatic disk, the hole in the shutter seems too far over compared with the hole in the plastic -- inside an automatic drive, the shutter isn't pushed over so far, so as not to engage with the little locking tab in the corner.

As it happens, these also became a fidget-widget; people would often be found mindlessly opening a disk's shutter, and then gradually squeezing the corner until it snapped shut, only to open it and do the same again over and over to relieve the boredom of a tedious task, such as printing a whole sheet of paper, or writing many thousands of bytes to permanent storage, or talking with a salesman.

There were other changes to the design of 3.5" drives over time too, such as going double-sided, or increasing the information density, but these were all generally introduced in backward compatible ways, so that the newer disks always worked in the older drives.

The only incompatibility I think I remember is that the very first single-sided, single-density drives had trouble if you attempted to format a disk in them that had already been formatted for the later drives (for the longest time, blank disks were *blank* -- the user had to format them first, because of the variety of systems they could be used in). I'm sure someone here who still has a 1983 drive can correct me if I'm wrong about this.

Edited: 17 May 2006, 1:43 p.m.

#16

Quote:
It was almost as bad an idea as CDROM drives that required disk caddies.

At the time they were great. You could change a disc in seconds and chuck the one you'd removed onto the console bench. Back then discs cost a *lot* more than 0.50 because there was no one-off, end-user process for minting them. A disc case that could be put into the reader was a clever way of protecting the disc while greatly simplifying its handling.

Cameron

#17

Quote:
Those things were a supremely BAD idea. What could the designer possibly have been thinking... or smoking...

Making the mechanism fully automatic required re-desingning the drive itself. This is a useful protective mechanism that worked with all the current drives.

#18

Well it seems that you can get these disks fairly cheap:

Manual Shutter disks for Mike

Etienne


#19

How on earth did you find that? You will notice who bought those.

I now have 2 of these in unopened boxes of 10 and one box of 10 that has been opened. 30 discs... woopie! Now, if I only had something to do with them. People collect the strangest things, don't we?

Edited: 20 May 2006, 1:32 p.m.


#20

Hello Mike,

Glad you got them ;-)

Yes, we do collect strangest things!

Did you ever encounter this sample of mine:

Etienne

Edited: 20 May 2006, 4:59 p.m.


#21

Are you just collecting the box or the cheese, too?

Marcus


#22

Just the labels, we're called tyrosemiophiles.

The cheese smell could also protect my calculators from theft but I prefer to eat it -:)

Etienne


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