8" disk drive questions...

[Chuck Guzis]

On 10/31/21 9:57 AM, geneb via cctalk wrote:
> 
> I'm working with the developer of the Applesauce disk imaging tool in
> order to iron out some issues with 8" disk support.
> 
> I'm using a Qumetrak 842 disk drive that's got support for both double
> and single-sided media.  This means that it's equipped with two index
> hole sensors, slightly offset from one another.  It's my understanding
> that single-sided media has the index hole in one spot on the jacket,
> and double-sided media has one in a slightly different location.
> 
> The issue at hand is some NIB Dysan double-sided 8" media I have - the
> disks have index holes in the jacket in both locations.  Is this
> typical, or do I have some weird "special" disks on my hands?  The
> Applesauce author posits that the combination of the dual-sensor drive
> and the dual-hole media wouldn't typically find themselves together.  Is
> this accurate?  If it's not, how would a system contemporary with the
> media have handled the two index holes?

Gene, are you certain that these aren't "flippy disks" (two index
apertures)?

But I've seen what you describe.

I recall one occasion where I received the single-double type that you
describe and having to cover the single-sided hole to get to the other
side of the disk.

--Chuck