8 May
2016
8 May
'16
1:09 p.m.
> I have
reason to believe that the CDC 9428 and 9429 are identical
> except that the 9429 is jumpered for 80 tracks and the 9428 is
> jumpered for 40 tracks... but I'm not 100% sure.
* On Sat, May 07, 2016 at
11:17:50PM -0600, Eric Smith <spacewar at gmail.com> wrote:
> They would have to have different heads, if the 40 track model was
> standards-compliant and industry-compatible. Ahhh... of course, I should have thought of that.
I am even more cautious about using the 9428 manual for 9429
service, then.
Actually, many lines of drives, such as the Tandon TM100 have the same
circuitry for both the 48tpi and 96tpi variants. (and the TM100-4M at
100tpi)
A specific exception, that I don't think is relevant here, is that a 1.2M
drive will have a few circuitry changes V a 48tpi/"360K" model, such as
RWC (reduced write current), and sometimes a 300RPM V 360RPM control.
But, a "360K" (CDC 9428) V "720K" (CDC 9429) are likely to be
virtually
identical other than step distance and head width.