H89 disk speed test

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Bob Russo

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Aug 9, 2022, 9:05:32 PMAug 9
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Hi folks, 
I'm in the process of restoring a Heath H89 for a computer museum.  After several chips, caps, vaporized traces and keyboard work, it's looking pretty good.  Memory test passes. Display test looks great.  
I just reinstalled the floppy & ran the memory speed test (G7372).  The 60Hz marks on the wheel were very close to stopped under a fluorescent light.  The screen showed no where near 200, but 023660.  It danced around that number a little, but not much.  I was able to stop 60Hz marks with a very small tweek to the speed pot, now the screen shows 024142, plus or minus a few.
Is this normal behavior for some drive/controller combinations, or do I have a more serious problem here?
I plan to read up on the process to create a boot drive via serial/windows computer and attempt that next.
The drive is a Siemens FDD100-5, controller 85-2601-1
Thanks

Joseph Travis

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Aug 9, 2022, 11:07:19 PMAug 9
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You need to insert a 10 sector, hard sectored floppy into the drive in order for the H89 to correctly display the speed.

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Glenn Roberts

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Aug 10, 2022, 5:01:56 AMAug 10
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Right. The software uses the interrupt-driven 2ms TICCNT timer to measure the time between index holes…

Sent from my iPad

On Aug 9, 2022, at 11:07 PM, Joseph Travis <jtravi...@gmail.com> wrote:



Bob Russo

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Aug 10, 2022, 9:52:19 AMAug 10
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Thanks!
I guess the next project is a disk punch.

rand...@hotmail.com

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Aug 10, 2022, 10:26:27 AMAug 10
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