esdi hard drive identification - test-drb@ccmp.vtda.org

4 Sep 1999

...
 One of the surplus stores in my area just got in a load
of 5-1/4 form factor
hard drives. They look just like the ones my PDP-11/73's use (RD51 or 52,
can't recall). I believe my controller is a RQDX2, not a RQDX3. My drives
are 30mb. 
If they're for use with a RQDX2 or 3, they'd better be MFM (ST-506)
interface drives, not ESDI drives!  The connectors are the same, but
the signals are quite different.

...
 I was wondering, is there an easy way (short of looking
up the model
numbers) to visually determine if any of the drives are ESDI and might work
with my 11/73? 
Most any ST506 drive can be pressed into use with a RQDX1/2/3, with
an appropriate low-level format (via XXDP's ZRQB?? or ZRQC?? formatter).

The RD52 is a Quantum Q540 or an Atasi AT3046.  Capacity around 30 Mbytes.
There was also a CDC drive used, I'm not sure what the model number was.

The RD53 is a Micropolis 1325 (early ones) or 1335 (later ones).  Capacity
around 65 Mbytes.

The RD54 is a Maxtor XT2190.  Capacity around 140 Mbytes.  Won't work with
a RQDX1/2, only a RQDX3.

If you're really interested in pursuing the use of random MFM drives
on your RQDX2 or RQDX3, pay close attention to the notes that Terry
Kennedy has kept in

  ftp://ftp.spc.edu/third-party-disks.txt

for the past decade or so.  There are many details about the use of
non-DEC-branded-drives, and in particular there are some suggestions for
formatting them with XXDP.

-- 
 Tim Shoppa                        Email: shoppa(a)trailing-edge.com
 Trailing Edge Technology          WWW:   http://www.trailing-edge.com/
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