[Coco] Formatting HD floppies w/ modified controller.

[Neil Morrison]

----- Original Message ----- 
From: "Gene Heskett" <gene.heskett at verizon.net>

> Dyson used to make a standard test disk, but I haven't seen one of them
> puppies in 20 years, Robert.  It was also quite pricey, about 100 bucks.
> Made for the servicers of the drives, it contained tracks with such
> things as azimuth wobble, tracks with lots of noise in the guard bands,
> that sort of thing.  You could align a 40 track drive to an accuracy in
> the micron range with it.  The one I saw was for 40 track (48 tpi) drives,
> and I'd assume they also made one for the 80 track (96 tpi) stuff, but I
> never had the pleasure of seeing one of those.

Radio Shack sold one also - it had software that used the actual computer to 
display the results.

> The biggest downfall for Dysons potential market was that you absolutely
> couldn't convince the techs of the day that it couldn't be copied.  They
> had no concept of the requirements of the drive that actually made that
> disk, and I've seen techs trying to use copies and wondering why they
> weren't seeing the stuff on the scope that the original disk could do.

Yes, although there was SOME point in using a copy for anything not 
involving a 'catseye' track.

Neil