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phogren
July 27th, 2009, 10:07 AM
Going through a big pile of C64 disks I found a few that are hard sectored, meaning they have a bunch of index holes on the floppy disk not just one. I think it was the Northgate that used them but I'm not sure. So far I have found two and will send them to anyone that might need them for just the postage. May be more

Chuck(G)
July 27th, 2009, 11:35 AM
Going through a big pile of C64 disks I found a few that are hard sectored, meaning they have a bunch of index holes on the floppy disk not just one. I think it was the Northgate that used them but I'm not sure. So far I have found two and will send them to anyone that might need them for just the postage. May be more

Do you perhaps mean North Star? They used HS floppies.

phogren
July 27th, 2009, 12:23 PM
I knew it was North something!

MikeS
July 27th, 2009, 07:31 PM
I knew it was North something!
How many holes?

leaknoil
July 27th, 2009, 07:34 PM
Some of the home computers didn't care about the timing holes. They may have been used on a 64 but, I don't remember if it was one that didn't or not.

Northstar is 10 hs I think. I really should know since there is an Advantage taking up half my couch in the living room but, too much information and too little brain cells left.

Dwight Elvey
July 28th, 2009, 05:38 AM
Hi
On a 10 hard sectored, there will be 11 holes ( 10 sectors and one index ).
The main machines that used them were NorthStar, Heathkit H89/H8 and
Polymorphic 8813. There were a few others but I don't recall the names.
I have all three but I've not had time to fiddle with my N*. Both Heathkits
and the Polymorphic are running.
I don't need any disk as I punch my own. I built a jig using an old
SA400 drive frame that I had in my junk box ( someone else had removed
the electronics ).
There was a machine that used 5.25 16 hard sectored but I don't know which
that was. I have another computer that uses 8 in. 16 hard sectored
( my Nicolet 1080 ).
Dwight

RetroHacker_
July 28th, 2009, 05:48 AM
Most home computers completely ignore the index hole, so you could definitely have used hard sector floppies on them. The C64, Apple II and Atari computers for sure - and probably more. These machines used single sided drives, and you could make "flippy" disks by punching an extra write protect notch in the other side of the disk, and turning it over. Since the machine ignores the index hole, it doesn't matter than it's now in the wrong place.

I know that the Tandy Color Computer actually does use the index pulse, because to make flippy disks for that, you have to notch the edge AND punch an index hole through both sides of the jacket without damaging the media.

I have a Heathkit H8, which uses hard sector floppies. I'd be very interested in seeing how you built your disk punch, Dwight. Do you have any pictures of it?

-Ian

Dwight Elvey
July 28th, 2009, 07:15 AM
Hi
I looked for pictures but didn't find much.
It isn't really too much. First you need to remove
all the old pieces and parts.
I then made a small block of aluminum that mounted
on the frame behind where the index hole was.
Next I made another block that mounted on the
hinged disk clamp. I milled these blocks on my
table top lathe.
I had just enough clearance between the two so
that the disk could rotate smoothly and not jam
in the cover.
I put some clamps on my drill press to align
the drive and drill bit to be over an index hole,
of a disk, and the lower block.
I installed the block that goes on the hinged
clamp.
I then line drilled the two blocks with ( as I recall )
a #93 drill. I used the shank of the same drill
as my punch by cutting two flukes like most hole
punches have ( used a dremel here and cut-off disk ).
As I recall, I temporarily glued a gear to the disk
side to use as an index mark and then used a
center drill to mark the flywheel. I marked 10
holes plus the index. The gear was 100 teeth.
An index wheel would have worked here as well.
I made a pointer to these marks and attached
it to the frame.

To use:
As I closed the disk, I'd simultaneously slide the
drill shank through the index hole and set the
flywheel to the index mark. If is not as hard
as it sounds.
Then I just rotate the flywheel to each of the
ten locations and punch the hole.
Dwight

leaknoil
July 28th, 2009, 07:39 AM
There was a machine that used 5.25 16 hard sectored but I don't know which
that was.

I think Vector Graphics did.

chuckcmagee
July 28th, 2009, 10:38 AM
Hehe, here we go again! I owned one and I still have to fire up google to find out if it's graphic or graphics. Yep, it's Vector Graphic Inc.

Anyway, yes on the 16 hard sector thing. I almost got a Vector Graphic on ebay until I remembered that not so small fact. The Northstar guys are enough trouble as it is.

barythrin
July 28th, 2009, 11:28 AM
A drive or two for the PET required hard sector floppies I believe (if you're trying to figure out why they'd be with Commodore stuff).

MikeS
July 30th, 2009, 05:15 PM
A drive or two for the PET required hard sector floppies I believe (if you're trying to figure out why they'd be with Commodore stuff).
---
Really? Any confirmation anywhere that a PET drive *required* HS disks?

I used HS disks with my PETs & C64s, but only because in their day they were cheap since PCs couldn't use them; when I got my Vector Graphic (no 'S' ;-) ) systems I transferred all the PET stuff to normal DS/DD disks so I could use the (now rare and expensive) HS disks in the VG. Times change...

w8an
August 25th, 2009, 07:12 PM
Do you still have these disks available? Are they 16 sector (seventeen holes). I have a Micropolis drive that requires this and I don't have any disks anymore... :(

..Steve

phogren
August 26th, 2009, 06:42 AM
Yes I still have them but they are not 16/17 holes

MikeS
August 26th, 2009, 06:49 AM
Do you still have these disks available? Are they 16 sector (seventeen holes). I have a Micropolis drive that requires this and I don't have any disks anymore... :(

..Steve
The drive doesn't care, it's the controller; what are the make/model of the computer, controller and drive(s)?