[TUHS] unix v4 tape found

[TUHS] unix v4 tape found

[Rob Pike via TUHS]

https://phanpy.social/#/hachyderm.io/s/115504720323483804

From mastodon:

<https://discuss.systems/@ricci>
Rob Ricci
ricci@discuss.systems <https://discuss.systems/@ricci>

While cleaning a storage room, our staff found this tape containing #UNIX
<https://discuss.systems/tags/UNIX> v4 from Bell Labs, circa 1973

Apparently no other complete copies are known to exist:
gunkies.org/wiki/UNIX_Fourth_E
<https://gunkies.org/wiki/UNIX_Fourth_Edition>

We have arranged to deliver it to the Computer History Museum

[TUHS] Re: unix v4 tape found

[Al Kossow via TUHS]

On 11/6/25 2:41 PM, Rob Pike via TUHS wrote:

> We have arranged to deliver it to the Computer History Museum
> 

another day, another project.

[TUHS] Re: unix v4 tape found

[Warren Toomey via TUHS]

On Thu, Nov 06, 2025 at 02:44:38PM -0800, Al Kossow via TUHS wrote:
> On 11/6/25 2:41 PM, Rob Pike via TUHS wrote:
> 
> > We have arranged to deliver it to the Computer History Museum
> 
> another day, another project.

Fingers crossed that it reads OK, can't wait to add it to the
Unix Archive here :-)

Cheers!
	Warren

[TUHS] Re: unix v4 tape found

[Dave Horsfall via TUHS]

On Fri, 7 Nov 2025, Warren Toomey via TUHS wrote:

> Fingers crossed that it reads OK, can't wait to add it to the Unix 
> Archive here :-)

That would depend on how the tape was stored; it'd likely require a 
specialist to read it.

-- Dave

[TUHS] Re: unix v4 tape found

[Bakul Shah via TUHS]

On Nov 6, 2025, at 2:54 PM, Warren Toomey via TUHS <tuhs@tuhs.org> wrote:
> 
> On Thu, Nov 06, 2025 at 02:44:38PM -0800, Al Kossow via TUHS wrote:
>> On 11/6/25 2:41 PM, Rob Pike via TUHS wrote:
>> 
>>> We have arranged to deliver it to the Computer History Museum
>> 
>> another day, another project.
> 
> Fingers crossed that it reads OK, can't wait to add it to the
> Unix Archive here :-)

What is the state of the art in reading old tapes these days?

[TUHS] Re: unix v4 tape found

[Cameron Míċeál Tyre via TUHS]

Rob,

That's awesome. It's evidence for my often made argument, that we just don't know what's lying in closets and storage rooms or gathering dust on the very top shelf in some obscure room of some institution or other.

A great find and to second what Warren said, I hope it reads okay. If it was stored on its edge, it should be okay. If it was lying flat, there's more chance of corruption from passing muons.

Best to all,

Cameron


-------- Original Message --------
On Thursday, 11/06/25 at 22:42 Rob Pike via TUHS <tuhs@tuhs.org> wrote:
https://phanpy.social/#/hachyderm.io/s/115504720323483804

From mastodon:

<https://discuss.systems/@ricci>
Rob Ricci
ricci@discuss.systems <https://discuss.systems/@ricci>

While cleaning a storage room, our staff found this tape containing #UNIX
<https://discuss.systems/tags/UNIX> v4 from Bell Labs, circa 1973

Apparently no other complete copies are known to exist:
gunkies.org/wiki/UNIX_Fourth_E
<https://gunkies.org/wiki/UNIX_Fourth_Edition>

We have arranged to deliver it to the Computer History Museum

[TUHS] Re: unix v4 tape found

[Al Kossow via TUHS]

On 11/6/25 3:06 PM, Dave Horsfall via TUHS wrote:
> On Fri, 7 Nov 2025, Warren Toomey via TUHS wrote:
> 
>> Fingers crossed that it reads OK, can't wait to add it to the Unix
>> Archive here :-)
> 
> That would depend on how the tape was stored; it'd likely require a
> specialist to read it.
> 
> -- Dave
> 

https://oldbytes.space/@bitsavers/115505135441862982

This is rare enough that I'm pushing the recovery of it up
near the top of my project queue.

[TUHS] Re: unix v4 tape found

[Al Kossow via TUHS]

On 11/6/25 3:08 PM, Bakul Shah via TUHS wrote:

> What is the state of the art in reading old tapes these days?
> 

taping off the head read amplifer, using a multi-channel high speed analog to digital
converter which dumps into 100-ish gigabytes of RAM, then an analysis program Len
Shustek wrote. https://github.com/LenShustek/readtape

It is a 70s 1200ft 3M tape, likely 9 track, which has a pretty good chance of being
recoverable.


early 80's Memorex, on the other hand (like Sun and UCB liked to use)

[TUHS] Re: unix v4 tape found

[segaloco via TUHS]

On Thursday, November 6th, 2025 at 14:42, Rob Pike via TUHS <tuhs@tuhs.org> wrote:

> https://phanpy.social/#/hachyderm.io/s/115504720323483804
> 
> From mastodon:
> 
> https://discuss.systems/@ricci
> 
> Rob Ricci
> ricci@discuss.systems https://discuss.systems/@ricci
> 
> 
> While cleaning a storage room, our staff found this tape containing #UNIX
> https://discuss.systems/tags/UNIX v4 from Bell Labs, circa 1973

For V4, would the entirety of the system have been placed on a
single tape, or are we looking at a situation here where this may
be a partial system?

- Matt G.

[TUHS] Re: unix v4 tape found

[brantley coile via TUHS]

My V7 tape was on one 2400 foot reel. 

Brantley

> On Nov 6, 2025, at 6:25 PM, segaloco via TUHS <tuhs@tuhs.org> wrote:
> 
> On Thursday, November 6th, 2025 at 14:42, Rob Pike via TUHS <tuhs@tuhs.org <mailto:tuhs@tuhs.org>> wrote:
> 
>> https://phanpy.social/#/hachyderm.io/s/115504720323483804
>> 
>> From mastodon:
>> 
>> https://discuss.systems/@ricci
>> 
>> Rob Ricci
>> ricci@discuss.systems https://discuss.systems/@ricci
>> 
>> 
>> While cleaning a storage room, our staff found this tape containing #UNIX
>> https://discuss.systems/tags/UNIX v4 from Bell Labs, circa 1973
> 
> For V4, would the entirety of the system have been placed on a
> single tape, or are we looking at a situation here where this may
> be a partial system?
> 
> - Matt G.

[TUHS] Re: unix v4 tape found

[Al Kossow via TUHS]

On 11/6/25 3:25 PM, segaloco via TUHS wrote:

> For V4, would the entirety of the system have been placed on a
> single tape
If you look at the packing of the 1200 ft reel, it appears to take
about 1/3 of the tape, so at 800 bytes/inch,
on the order of a few megabytes allowing for record gaps.

[TUHS] Re: unix v4 tape found

[segaloco via TUHS]

On Thursday, November 6th, 2025 at 15:36, Al Kossow via TUHS <tuhs@tuhs.org> wrote:

> On 11/6/25 3:25 PM, segaloco via TUHS wrote:
> 
> > For V4, would the entirety of the system have been placed on a
> > single tape
> 
> If you look at the packing of the 1200 ft reel, it appears to take
> about 1/3 of the tape, so at 800 bytes/inch,
> on the order of a few megabytes allowing for record gaps.

Whoops, yes I was thinking of the tapes mentioned in bproc,
separate from the distribution tape.

- Matt G.

[TUHS] Re: unix v4 tape found

[steve jenkin via TUHS]

Links for those playing along at home on “What could possibly go wrong…”

CHM (and Al? ) as professional archivists / recovery will be more than aware of all this.

> On 7 Nov 2025, at 10:14, Al Kossow via TUHS <tuhs@tuhs.org> wrote:
> 
> early 80's Memorex, on the other hand (like Sun and UCB liked to use)

====================

Sticky-shed (hygroscopic binder)
	<https://en.wikipedia.org/wiki/Sticky-shed_syndrome>

Affected Tape

	Tapes affected by sticky-shed are those that were made by Ampex/Quantegy 
		such as 406/407, 456/457, 499, 
	and consumer/audiophile grade back coated tapes 
		such as Grand Master and 20-20+,[citation needed] 
	as well as those made by Scotch/3M 
		including professional tapes such as 206/207, 226/227, 262 (though not all 262 is backcoated and therefore isn't affected), 808, and 986 
	as well as audiophile tapes such as "Classic" and "Master-XS”.

====================

Magnetic Tape Binder Breakdown
	a.k.a. Polyurethane Binder Deterioration (Sticky Shed Syndrome / Soft Binder Syndrome)
	<https://psap.library.illinois.edu/collection-id-guide/softbindersyn>

	Test for Sticky Shed Syndrome BEFORE attempting playback.

====================

Council on Library and Information Resources

2. What Can Go Wrong with Magnetic Media?
	<https://www.clir.org/pubs/reports/pub54/2what_wrong/>

	2.5 Magnetic Tape Recorders
		This document is primarily concerned with tape media, not tape recorders. 
		However, in discussing what can go wrong with media, recorders must be mentioned. 

====================
--
Steve Jenkin, IT Systems and Design 
0412 786 915 (+61 412 786 915)
PO Box 38, Kippax ACT 2615, AUSTRALIA

mailto:sjenkin@canb.auug.org.au http://members.tip.net.au/~sjenkin

[TUHS] Re: unix v4 tape found

[Charles H. Sauer via TUHS]

On Nov 6, 2025, at 11:22 PM, steve jenkin via TUHS <tuhs@tuhs.org> wrote:
> 
> Links for those playing along at home on “What could possibly go wrong…”
> 
> CHM (and Al? ) as professional archivists / recovery will be more than aware of all this.
> 
>> On 7 Nov 2025, at 10:14, Al Kossow via TUHS <tuhs@tuhs.org> wrote:
>> 
>> early 80's Memorex, on the other hand (like Sun and UCB liked to use)
> 
> ...
> https://en.wikipedia.org/wiki/Sticky-shed_syndrome
> 
> ...
> https://psap.library.illinois.edu/collection-id-guide/softbindersyn
> 
> ...
> https://www.clir.org/pubs/reports/pub54/2what_wrong/

All of this is speculative until recovery is attempted.

HOWEVER, I’m cautiously optimistic, based on experience the last several years with over a hundred audio tapes from the 1960s and 1970s. Typically these were 1/4” tape on 7” and 10.5” reels. Many of them were oriiginally recorded by me, but over half recorded by others, who predicted that “baking” would be appropriate. One reel had deteriorated unrecoverably. A few had minor shedding problems. All the rest exhibited no problems when I digitized them using tape machines dating back to the 1970s.

Charlie

P.S. Most of the recordings made by others may or may not become publicly available at some point. The most interesting ones I recorded are available at https://technologists.com/60sN70s/

--
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