working magnetic drum stores?

From: Ethan Dicks <>
Date: Tue Mar 30 20:11:57 2004

On Tue, Mar 30, 2004 at 01:00:21PM -0800, Tom Jennings wrote:
> LGP-21 fixed-head-platter mechanical memory (main store,
> not "disk") the heads sit crashed (sic) and lift when up to
> speed. The platter surface has fine scoring -- it's normal. It's
> only 80 bits per inch. Nickel plated steel. In fact, there's
> little springs that press the heads DOWNWARD.

Sounds a bit like the DEC DF-32 - 1/4" steel platters plated with something
(nickel?) The drive motor has a seperate power switch from the electronics,
so that if you have to service the controller or read/write hardware, you
can leave the disk turning. You'd only have to spin down if you wanted to
work inside the HDA.


Ethan Dicks, A-130-S      Current South Pole Weather at 31-Mar-2004 02:11 Z
South Pole Station
PSC 468 Box 400       Temp -86.3 F (-65.7 C)    Windchill     -129 F (-89.5 C)
APO AP 96598          Wind   8.9 kts Grid 049   Barometer 673.9 mb (10856. ft)
Received on Tue Mar 30 2004 - 20:11:57 BST

This archive was generated by hypermail 2.3.0 : Fri Oct 10 2014 - 23:37:07 BST