Date   : Mon, 03 Feb 1992 23:08:20 GMT
From   : cis.ohio-state.edu!zaphod.mps.ohio-state.edu!sdd.hp.com!news.cs.indiana.edu!lynx!hydra.unm.edu!dmckeon@ucbvax.Berkeley.EDU (Denis McKeon)
Subject: Summary - Re: 8-inch disk format? (was: The Original True Blue IBM PC)

I'm posting a summary mostly to save those who are just now seeing this
thread from feeling like they should answer!  I've gotten most of the
info I wanted and more - 13 messages in 72 hours!  However, if anyone
else has a phone number or address of a commercial disk/data conversion
shop that they were happy with - please e-mail it to me.

The summary:

The  CPT SSSD 8 inch disks are 77 tracks, 16 sectors of 256 bytes.  
    77 * 16 * 256 = 315,392 = 308Kb

Most CPM SSSD 8 inch disks are 77 tracks, 26 sectors of 128 bytes.  
    77 * 26 * 128 = 256,256 = 250.25Kb

(Thanks to Ralph Becker-Szendy for being 'firstest with the mostest' -
sending a very informative reply covering all manner of 8 inch disk
arcana - hard/soft sector, SS/DS SD/DD, etc. - less than 4 hours after
I posted the request - and to John D. Baker for confirming the 16*256
format from his experiments with some CPT disks.

Four respondents suggested reading data from the printer port, but
unfortunately the degree of access I have to the CPT does not extend
that far - I can use the CPT to print to paper, but not to tickle its
backside or innards.  Likewise for running Kermit or PIP.

Two respondents suggested using any commercial service that uses the
Shaftstall conversion package - apparently a very good product, but
naturally not cheap.  Several people gave detailed descriptions of
various 8 inch disk formats and layouts.

So, I'd like to thank:

    Ralph Becker-Szendy 
    John D. Baker 
    Alan J. Richer              
    Bill Marx
    Charles Lasner 
    Clarence Wilkerson
    Don Maslin
    Donald Nichols 
    John M. Mills
    Richard H. Gumpertz
    Roger Ivie
    Russ Kepler 
    entropy@gnu.ai.mit.edu
    Chris McEwen

Also, for those of you who offered to track down leads to services, or
offered other help - thank you all!  It is just so darned nice to be
able to ask hundreds of strangers for advice, and get so much so fast.  
I may be in contact with a few of you by e-mail or off-line soon.

Everybody who responded is being mailed a copy of this summary, and
if the sendmail gods are willing, you'll even receive it. :-) 

Thanks again,
--
Denis                                   Good.   Fast.   Cheap.
dmckeon@hydra.unm.edu                       Pick two.