24 Feb
2011
24 Feb
'11
8:33 a.m.
To clarify, Data General did not use/supply DECtape/Linc Tape drives, rather
the company Computer Operations, Inc. in Beltsville Maryland supplied "Linc
Tape" drives and software for Data General systems in the 1970s (starting in
1971). The drives were initially the standard side-by-side DECtape format,
and l. The "alternate format (wrapped the opposite direction around the
reel)" drive format that Rich referred to was introduced later in that
decade by Computer Operations for the DG systems. COI also created a
minimalist LincTape Operating System (LTOS) for DG along with a tape driver
library.
The National Weather Service (NWS) and some military systems used these
systems with Novas in the 1970s, and at least one electronics manufacturing
plant in Mexico used Nova 2s with COI LincTape drives through 2001(!).
Bruce Ray
----- Original Message -----
From: "Ian King" <IanK at vulcan.com>
To: "General Discussion: On-Topic and Off-Topic Posts"
<cctalk at classiccmp.org>
Sent: Thursday, February 24, 2011 12:39 AM
Subject: RE: Bit of DEC Trivia
I did not realize the DECtape/Minitape format was used by Data General.
Might you have model/part numbers? I'd like to know more about that.
Thanks -- Ian
________________________________________
From: cctalk-bounces at classiccmp.org [cctalk-bounces at classiccmp.org] On
Behalf Of Rich Alderson [RichA at vulcan.com]
Sent: Wednesday, February 23, 2011 2:19 PM
To: 'General Discussion: On-Topic and Off-Topic Posts'
Subject: RE: Bit of DEC Trivia
From: Mr Ian Primus
Sent: Wednesday, February 23, 2011 11:16 AM
--- On Wed, 2/23/11, Jerome H. Fine <jhfinedp3k at
compsys.to> wrote:
> From: Jerome H. Fine <jhfinedp3k at
compsys.to>
> Subject: Re: Bit of DEC Trivia
>> Guy Sotomayor wrote:
>> On Feb 23, 2011, at 9:40 AM, schoedel at
kw.igs.net
>> wrote:
>>> On Wed, 23 Feb 2011 08:25:42 -0800, Guy
Sotomayor
>>> wrote
>>>> Q: How many DECTapes (images) can fit
on a 1TB HDD?
>>> All of them?
>> YES! Finally someone got it! :-)
>> DEC never shipped millions of DEC Tapes.
> At one time, the PDP-11/44 and the VAX 780 used
the TU58 media as
> distribution tapes. How many installations existed?
Ah, but you're forgetting. TU58's aren't
true DECTapes. The TU-58 (DECTape
II) is really more of a modified DC150 format - the true DECTapes are
little round reels. They were used on PDP8 and PDP12 machines primarily.
DECtapes (originally called "Microtapes") were invented for the PDP-4, and
were used on the PDP-4, PDP-5, PDP-6, PDP-7, PDP-8 family, PDP-9, PDP-10,
PDP-11 family, and PDP-15. They were also used on Data General systems,
and the alternate format (wrapped the opposite direction around the reel)
called LINCtape was used on LINC, LINC-8, and PDP-12 systems. There were
three drives, the 555, the TU-55, and the TU-56; the latter two were used
on 12-, 16-, 18- and 36-bit systems.
Until the advent of the floppy disk, DECtape/LINCtape was common on a lot
of minicomputers, and even on mainframes.
Rich Alderson
Vintage Computing Sr. Server Engineer
Vulcan, Inc.
505 5th Avenue S, Suite 900
Seattle, WA 98104
mailto:RichA at vulcan.com
mailto:RichA at LivingComputerMuseum.org
http://www.LivingComputerMuseum.org/=