> On Sep 7, 2016, at 2:45 PM, Al Kossow <a...@bitsavers.org> wrote:
>
>
>
> On 9/7/16 11:21 AM, Paul Koning wrote:
>
>> That would fit the IBM 2315 if indeed it used one sector notch for each
>> sector (it has 8 per track).
>>
>
> and 100 TPI
>
> Original Diablo drives were also 100 TPI, and used silver colored heads,
> moving to 200 TPI and the more
> common white ceramic heads.
>
> Apparently, the 100 TPI Diablo heads are extremely difficult to find today. I
> remember all the 100 TPI
> Diablo drives at a friend's company getting converted to 200.
TPI, as in "transitions per inch"?
I vaguely remember that the 1311 (20 sectors of 200 digits each per track) used
silvery colored heads. I wonder if those are the same. They were pretty
sturdy; one day when we had a hydraulic leak, the FE just cleaned heads and
pack with isopropyl alcohol, fixed the leak, and put the drive and pack back
into service.
paul
