----- Original Message -----
From: "James G. Sack (jim)" <[EMAIL PROTECTED]>
To: "Main Discussion List for KPLUG" <[email protected]>
Sent: Tuesday, June 27, 2006 11:28 AM
Subject: Re: old terms still familiar today (Was:top/bottom posting...)
deeb wrote:
We had a 2 meg (!) drum drive for use as a aid to doing CTD casts (
Conductivity, Temp and Depth.)
It was a sealed unit driven by a 1850 rpm A/c motor.and it had a Rhodium
plated drum
It was mounted on the second deck in a dry airconditioned lab space.
Unfortunately the motor acted a a sort of gyroscope and wiped the
read/write heads out in a short period of time.
The drive cost about $8 K (1972) and was deemed SOTA.
Repair estimate was 3-4 K so we never got any use from it !
Hi dee-
Do you remember how many tracks? Or anything about the head mechanisms?
Oh .. sealed, eh? No inspection windows?
For the benefit of innocent bystanders, a drum would have as many heads
as there were tracks, so there was no "seeking", no seek latency. Izzat
right? Sorta like a edison wax recordings with multiple pickups. Ohh,
nobody remembers those either? (Well, actually, neither do I, but I
remember pictures of them.)
Can you explain the "gyroscope-effect" damage. I don't follow.
..jim
The bearings on the unit were not robust. The motion of the ship from
wave action would normally not bother it but we took some severe pounding
both verically and sideways. The bearings started grinding and the drum
actully hit the heads. The were no inspection ports.
Don't know about track #'s
This item is probably too ancient to search !
dee
--
[email protected]
http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
--
No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.1.394 / Virus Database: 268.9.4/375 - Release Date: 6/25/2006
--
[email protected]
http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
