12 May
2020
12 May
'20
6:10 a.m.
On 5/11/2020 11:15 PM, Josh Dersch via cctalk wrote:
Hi all --
I'm restoring a Xerox Alto and I started going over the system's Diablo 30
drive. The heads are in bad shape; the bottom one is actually missing both
parts of the erase poles (so the black portion of the head no longer makes
a "t", it's just a black line). This means the head (in addition to not
being able to erase) also won't float due to the head having small cavities
in them. The upper head looks a little better but I'd love to find a set
of upper and lower heads if anyone has spares.
Then I get to learn how to align these things.
Thanks!
- Josh
I don't know if they would be compatible or not, but my inventory lists
Diablo part number 15428, Model 31 / RK03 Carriage + Heads Assembly.
(Perhaps I didn't want to remove the heads themselves). I suspect that
I got the part number off the assembly itself somewhere - I don't have
record of any illustrated parts breakdown for the diablo drive in my
manual database.
As I seem to have two of these assemblies, you could certainly have one
of them, say for something like shipping plus $25.
I don't know the differences between the model 30 and model 31 - but as
the capacity of the model 31 was apparently twice that of the model 30
(2.5MB vs 1.25MB) - with both being referred to as Series 30, with the
model 30 apparently short-lived production wise. The Series 30
maintenance manual, on the other hand, lists "Standard" and
"HI-Density"
of 12 million bits and 24 millions bits, respectively.
From what I read of the Alto online, its disk capacity
was 2.5MB -
implying the drive is a model 31 / hi density.
I don't remember now if these parts I have were from drives originally
on a DEC or DG system. If they really were from RK03's, then they would
be the high density flavor.
The box they are in are off-site in my storage unit (but well stored),
and I could retrieve them in a day or so if you are interested, but at
present I don't know if this is the entire assembly shown on page 5-3 of
the maintenance manual, or just a portion.
PS: I seem to recall a "Curious Marc" YouTube video featuring these
beasties along with the Alto they were part of.
JRJ