> >>/I hit on the idea of using 16mm move film plastic "cans". Much to my />>/surprise, I found that there is still an active market for these things. /
> On Mon, 8 Apr 2019, Kevin Monceaux via cctalk wrote:
> >/My small 16mm collection is stored on an open reel tape cart. /
> I wonder how tape rings would do on 16mm reels?
You mean the write rings?? They're fixed at the hub size....
As for write rings, most sites had more than they actually need, many
times over.? You really only need as many as you have tape drives...
I've always wanted to make an Olympics logo out of write wrings, but
never could find all the right colors.
I have a couple black ones around the gearshift in my car (like horseshoes).
--
Jeff Woolsey {{woolsey,jlw}@jlw,first.last@{gmail,jlw}}.com
Nature abhors straight antennas, clean lenses, and empty storage.
"Delete! Delete! OK!" -Dr. Bronner on disk space management
Card-sorting, Joel. -Crow on solitaire
> While on the subject of tape storage anyone know if it is still possible to get desktop/table top wire bins to hold tapes in canisters and/or reels? Not that I have that many tapes or anything like that. This would be more for display purposes than anything else.
>
> Something akin to this: ibm51xx.classiccmp.org/CCTalkPics/taperack.png
>
> Do they still make things like this or do I have to find it at university junk sale?
>
>
Those are exactly the "dish rack" things I have two of.? Of course, I
can't remember where I got them.
FWIW, I also have a small rack that holds, uh, 2x4x25 8mm data tapes in
their cases.? Said "dish rack" won't fit on top, though.
--
Jeff Woolsey {{woolsey,jlw}@jlw,first.last@{gmail,jlw}}.com
Nature abhors straight antennas, clean lenses, and empty storage.
"Delete! Delete! OK!" -Dr. Bronner on disk space management
Card-sorting, Joel. -Crow on solitaire
> From: Adrian Stoness
> someones bid on them eh hopefully not a scraper
Well, a scrapper would want to pay as little as possible, so anyone
who wanted to actually save the system should be able to get it.
There are a couple of bids on it, but the amounts are derisory.
I hope Christian's museum can get it!
Noel
This I didn't know.
I bought a Tektronix 4207 color graphics terminal without a keyboard
recently.? Finding the correct keyboard part number seemed to be a
process with great uncertainty, the VintageTEK folks said the correct
one was a 2468.? One of these was for sale on ebay for $300 - no way was
I paying that much!
So I tried one that looked like the keyboard in the TEK catalog of that
period, but with a different part number. The connector looked like the
right one though.? I got one off ebay, and I thought it was kind of
expensive, but it did work with the 4207 terminal.
What I didn't understand was a fascination with the black mechanical
Cherry switches the keyboard used.? These turn out to be extremely
popular with the 'gaming' community.? I don't know if the tektronix
keyboard can be used with a modern PC, I haven't looked at the interface
signals yet.? The modern PS/2 keyboard has a clock and data line, the
DEC LK201 used rs232, so what Tektronix used is anybody's guess.
> whats with the weird tag on this thread?
Oops, sorry.
Clicking on an address in the mailing list viewed as a web page via
http://www.classiccmp.org/pipermail/cctech/2019-April tries to fire up
MacOS X Mail, which I don't want because I use Thunderbird.? So I "Copy
Email Address" and paste it into a Thunderbird compose window To: field,
and it has
cctech at classiccmp.org?Subject=Re:%20'd_subject_line_mess&otherjunk.? I
copied that into the Subject: line, and thought something would do the
right thing with them upon receipt.? Oh well, there I go overestimating
the intelligence of software again.
--
Jeff Woolsey {{woolsey,jlw}@jlw,first.last@{gmail,jlw}}.com
Nature abhors straight antennas, clean lenses, and empty storage.
"Delete! Delete! OK!" -Dr. Bronner on disk space management
Card-sorting, Joel. -Crow on solitaire
> I've noted earlier that the vinyl "hanger strips" for 1/2" magnetic tape
> have been degrading, becoming brittle and simply breaking away,
> sometimes in small particles.
I have about a hundred tapes from various contributors, and have noticed
no age-related [1] deterioration of the seals, probably because mine
don't get handled very much.? About 1/3 of mine have the vinyl hanger
strips, another third the autoload seals, and the remainder are in the
bulky canisters (with several different closures).? I also have a couple
of tape racks (think "dish rack") that hold maybe thirty tapes, but the
canisters are too thick to fit in.
The tapes hang pretty well from the front lip of the wall-mounted wire
shelves (that you can get at most big-box-home-stores) I installed not
for that purpose.
The thing is, I've read and photographed most of them, so I don't need
[2] them anymore.? Their owners, like me, only wanted the data online,
not the media back. Most museums have more than they want or can use, as
well.? Some tapes have common-sense restrictions on redistribution
(Personally Identifiable Information, I think they call it nowadays).
I've even got some new, never-written ones.? But it pains me to trash
them, so I'm open to suggestions.
=
[1] I have dropped and broken a couple of them, but that was due to
insufficient age of the handler...? Some did not survive the reading
process due to oxide-binder aging, but the seals are fine.
[2] In many cases, usually by repurposing extra copies of software
distribution tapes, the most recent data is shorter than the original,
so the tails of older things past the EOF1 label and double tapemark can
be read without much difficulty.? The thing is, I didn't figure this out
until I'd been reading tapes a while, so the earlier ones may yield to
re-examining.
--
Jeff Woolsey {{woolsey,jlw}@jlw,first.last@{gmail,jlw}}.com
Nature abhors straight antennas, clean lenses, and empty storage.
"Delete! Delete! OK!" -Dr. Bronner on disk space management
Card-sorting, Joel. -Crow on solitaire
One of my RL02 drives (that sat for a long time) has developed what appears
to be a sticky head positioner.
But it's only a problem going from the full-retracted position to loading
track 0.
Once it's loaded, the drive will pass all seek and read/write tests.
It takes a surprising (to me) amount of force to pull the heads out into the
disk area (power off, no pack). When they're out there, the arm slides back
and forth easily.
Sometimes it won't load at all - push the load button, light goes out, disk
spins up to what sounds like normal speed, but the heads never move and the
Ready light doesn't come on.
There's supposed to be a Fault after 40 secs but that doesn't happen - it'll
sit there forever spinning but not ready.
If I turn off the power and remove the pack, and pull the positioner out
just enough to avoid opening the Heads Home microswitch (which causes a
Fault light), then it'll spin up, load track 0, and work fine the rest of
the day.
The manual (as usual) only recommends replacing the bad assembly for ease in
field servicing, which is deliberate.
But I don't have a DEC repairman and a warehouse full of parts handy... Is
there some kind of adjustment or lubrication I can do?
If I replace the positioner then I have to realign the heads (not too bad a
job on this drive, though).
Any ideas?
thanks
Charles
I've noted earlier that the vinyl "hanger strips" for 1/2" magnetic tape
have been degrading, becoming brittle and simply breaking away,
sometimes in small particles.
So I set off looking for a low-cost substitute--any hangers that I could
rustle up would probably be on their last legs at this late date.
I hit on the idea of using 16mm move film plastic "cans". Much to my
surprise, I found that there is still an active market for these things.
After getting a few samples, I've discovered that the 800' cans fit a
10.5" reel (virtually all of the tape that I get) quite well. I'm not
yet finished evaluating samples, but here's a photo of a can from Tuscan
Corporation holding a reel of tape:
https://i.imgur.com/KPKg75s.jpg
The cans are vented, so not hermetically sealed. In the case of film,
this is apparently done intentionally, as the acetate base of older film
outgasses acetic acid, which only hastens degradation.
If anyone's interested, I'll continue to post updates. I've got some
>from Larry Urbanski coming in Monday. Larry seems to have the lowest
price on these--about $5.75 each.
--Chuck
Back at VCF PNW, the subject of the Game of Life came up among some peers.
I recall messing with the BASIC version that supported 32 by 32 cells, and
there's also a FOCAL version that can do a whopping 11 by 11 cells.
This was simply not enough. So, I wrote my own implementation and came to
the realization of why more cells may not actually be better...it's
freaking slow!
https://github.com/drovak/pdp8life
I've improved the performance a bit using some caching and other tricks to
skip extraneous processing and twiddling of bits, but running in SimH for
lots of cellular life still takes a while. I haven't been able yet to try
it on the real hardware, and I can't say I'm looking forward to the speed
of the real machine either!
I'm working on a few new versions, which may get wrapped up into some
conditional assembly soon. One version will support both storage and
non-storage oscilloscopes with a VC8E. Another version may work to actually
reduce the size of the bitmap to increase speed; it's all a tradeoff, I
suppose.
Would love to hear some comments if anyone plays with this. And, if someone
significantly speeds things up while keeping the large playing field, I'll
be very happy to hear how!
Kyle
