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
Here's a list of some more stuff if anyone is interested in making
reasonable offers. Probably the last I will have before my demise
when my wife will likely send everything that's left to the skip.
MODULE Description QTY
NUMBER
M9202 UNIBUS connector 3
M9302 UNIBUS TERM 2
ADAC 1632TTL 3
ADAC 1616/32HCO 1
Plessey Peripherals 703185-100C & 701877-100 with Cable 1
Data Translation DT2769/EP057 REV F 1
Data Translation DT2769/EP057 REV J 1
Data Translation DT15150/EP075 Dual D/A Converter Module
M3106 4 Line Async Mux 1
M3106 4 Line Async Mux (w/broken handle) 1
M9060 LOAD MODULE 1
M8017-AA Async Line Interface 1
M8017 Async Line Interface (w/broken handle and berg socket) 1
G7273 NPG AND BUS GRANT CONTINUITY 5
RL Disk Drive Terminators 4
MV-II Function Select / SLU Module 1
A few modules that I ecpect are rare but of limited interest.
Terak 8510 Memory and Video module w/bulkhead connector 1
Terak 8510 Floppy Module w/bulkhead connector 2
Terak 8510 Floppy Module wo/bulkhead connector 2
Terak 8510 RS-232 Serial Module w/bulkhead connector 4
Terak 8510 RS-232 bulkhead connectors 3
Terak 8510 Video bulkhead connectors 2
Condition of the Terak Modules can not be verified.
They were functional at the time they were removed
but I no longer have any functional Teraks to test
them.
Shipping would be the smallest size USPS "If it fits it ships" box
so you can plan accordingly.
bill
a pity there are not? name? captions? ? ?for? those of? us that? do? not? travel? well to be? these in person.
Great photo? collection though!? Ed#
In a message dated 3/31/2019 8:46:29 AM US Mountain Standard Time, cctalk at classiccmp.org writes:
One last spam from VCF PNW 2019 ...
Send us your Photos!? We want to put together a shared photo album so thatpeople can see the event from different perspectives.? It's a Google Photosalbum, so if you are a Google Photos user sharing is easy.? If you are nota Google Photos user or you have concerns/questions please let me know andI'll work out an alternative.
The shared album can be found at:https://photos.app.goo.gl/e2rzk4iT4aHrQUoy6
Help us make VCF events better!? If you were at the event last weekend Ihave a quick survey that I'd like you to fill out.? The survey will help usshape future events.? The survey is anonymous; we are not collecting emailaddresses unless you want to get a chance at a free t-shirt.? (And eventhen, we are only using the email address for that single purpose.)
The survey link is: https://goo.gl/forms/V3DiyxwkpbIOCKn73
Direct feedback by email also works well.
Thanks,Mikemichael at vcfed.org or mbbrutman at brutman.com
> From: Guy Dunphy
> What I want to know is, how do front panels of historic computers so
> often get separated from the rest of the computer?
I suspect it probably happened a while back, before the start of the vintage
computer movement; you need to look at the decisions from the perspective of
back then. (As an example, back then, I was offered the complete PDP-11/45 of
my old group. I was up to my neck in contemporary, important, alligators - I
was on the IESG of the IETF at the time - and didn't have the time to deal
with saving it and moving it to my house; so I let it go - a loss I regret
terribly now.)
Here's what probably happened: the machines were about to be scrapped, and
saving the whole machine wasn't practical - often, in part, because those
machines were _huge_. (The CPU _alone_ of a KA10 would fill an entire room of
a normal house.) So, one has a limit to what one can do. So the choice is to
save the front panel alone... or to save nothing.
Noel
