H89 disk speed test

[Bob Russo]

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]

You need to insert a 10 sector, hard sectored floppy into the drive in order for the H89 to correctly display the speed.

--
You received this message because you are subscribed to the Google Groups "SEBHC" group.
To unsubscribe from this group and stop receiving emails from it, send an email to sebhc+un...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/67dbf5db-4de4-4ded-8869-02308fce6d40n%40googlegroups.com.

[Glenn Roberts]

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:



To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/CAGQDgBCD4%2B%3DF7_bEEXqwMEA-JWF38AKSV6XAqHZ9mG9yUMu2Dg%40mail.gmail.com.

[Bob Russo]

Thanks!

I guess the next project is a disk punch.

[rand...@hotmail.com]

https://deramp.com/vsg.html

Randy