I have described my replacement of a burst TU56 motor-run capacitor at
http://so-much-stuff.com/pdp8/tu56repair.html
I am particularly interested in feedback about the mounting solution -- is
it ingeniously simple, or a horrible kludge :-)?
There is a new version of my web-site there for the browsing, too (though
most of the log entries are still stubbed out).
Vince
Arno Kletzander <Arno_1983 at gmx.de> wrote:
> and the board installed bears the number "5017683-01-B1-P2" on the solder
> side and the designation "TZK-50" on the component side. I suppose this has
> to match the transport in order to have a functional unit (unless the TK70
> is smart enough to say: "You think I'm a TK50, so I'm gonna act as if I was
> one!").
I have previously heard of people connecting TK50 drives to TK70 controllers.
Supposedly it results in better performance. I don't know if you lose the
ability to write TK50 tapes this way or not.
This is the first time I hear about the opposite combination, but I have
to assume it works - whoever put it together obviously had it working,
otherwise the combo you have in your hands would not exist. But I won't
venture a guess as to whether that combo can read/write TK70 tapes or just
read TK50s.
MS
Here are two articles from eWeek (formerly PC Week) today. No, they're not
April Fools jokes.
http://www.eweek.com/article2/0,1759,1780863,00.asp
Top Five Vintage Computers Turn Dust into Dollars
http://www.eweek.com/article2/0,1759,1780855,00.asp
Old Computers Find New Homes as Vintage Artifacts
Disclaimer: I used to work for eWeek and still have some biases...
-----------------------------------------
Evan Koblentz's personal homepage: www.snarc.net
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Hello everybody;
some time ago I found a strange construction in a bin at the campus, which
I'd like to put back together in a way that makes it usable, nice-looking,
and doesn't conflict with collector ethics.
What I'm talking about is a DEC TK50Z-G3 external enclosure from which the
original TK50 (CompacTape I) transport was removed and replaced with a TK70
(CompacTape II) - which made it impossible to re-fit the cover, because the
TK70's bezel is about 3 mm (2/16") wider than the cutout in the housing
front panel. The access door in the panel's cutout is also in the way but
could be removed rather easily.
What was obviously not replaced however is the interface board which resides
above the transport. The device, when connected to my SPARCclassic and
interrogated by "probe-scsi" from the OBP "ok" prompt, reports as follows:
Target 5
Unit 0 Removable Tape Qualifier 50.
and the board installed bears the number "5017683-01-B1-P2" on the solder
side and the designation "TZK-50" on the component side. I suppose this has
to match the transport in order to have a functional unit (unless the TK70
is smart enough to say: "You think I'm a TK50, so I'm gonna act as if I was
one!").
I'm not in a hurry to get this working (I got some distribution CompacTapes
some time ago, but no leads on a matching DEC computer yet), but I'd like to
get an idea of what to do with it - which largely depends on whether this is
a sensible combination at all.
Yours sincerely
--
Arno Kletzander
Stud. Hilfskraft Informatik Sammlung Erlangen
www.iser.uni-erlangen.de
Sparen beginnt mit GMX DSL: http://www.gmx.net/de/go/dsl
I don't have the Simon computer but I do have the a Samsonite card table
that look just like the one in this cover photo.
http://www.widomaker.com/~cswiger/simon/cover1.jpg
I got it from an elderly neighbor 30 years ago. If anyone builds the
electronic brain I will provide the table.
Michael Holley
www.swtpc.com/mholley
There are at least two types of Simon documents available. I *think* the
first articles were the Radio Electronics Magazine series, and that was
followed by the reprint. The primary difference that I could see was the
color diagrams in the Radio Electronics Magazine series as opposed to
B&W on the reprints. When the discussion took place the last time on
this listserver, ISTR that Doug Salot had the reprints but they were
slightly different from what I have.
While I have the scans of the reprint (and they are still around here
... someplace), it would be nice to have the color wiring diagrams (they
are MUCH easier to see the specific wiring being described in the
figure.)
Also, ISTR that someone else on the list got a copy of the articles from
the Charles Babbage Institute and there were still some copyright
restrictions.
> From: "Charles E. Fox" <cfox1 at cogeco.ca>
> While looking for something else in old magazines I ran across a
> series of articles by Edmund C. Berkeley and Robert A. Jensen on the design
> and construction of the Simon relay computer. (Oct 1950 to Sept 1951 Radio
> Electronics) I can't find number 13 in Oct 1951, which is apparently a
> description
> of a different computer.
> Would it be worthwhile trying to scan these and try to get someone
> to post them?
I know this could be the start of YET ANOTHER thread "Oh I think
it's older than that..." but to avoid that, let's raise the
standard from opinion/hearsay to printed word.
Man I wish I had a collection of pre-1980 DATAMATIONs!
From _ENCYCLOPEDIA OF COMPUTER SCIENCE_(Van Nostrand), 1976:
KLUDGE
The word "kludge" is a term coined by Jackson Granholm in an
article "How to design a kludge" in _DATAMATION_ (February 1962).
The definition is given as "an ill-sorted collection of poorly
matched parts, forming a distressing whole". The design of every
computer contains some anomalies that prove to be annoying to the
users and wghich the designer wishes he had done differently. If
there are enough of these, the machine is called a "kludge".
By extention, the term has come to be applied to programs,
documentation, and even computer centers, so that the definition
is not "an ill-conceiverd and hence unreliable system that has
accumulated through patchwork, expediancy, and poor planning".
The first kludge article triggered five others ("How to maintain a
kludge", etc) in subsequent issues of _DATAMATION_. Four of the
articles may be found in the book _FAITH, HOPE AND PARITY_ edited
by Josh Moshman, Thompson Book Company, 1966.
-- F. Gruenberger
[Said book found at abebooks...]
All:
I've been corresponding for months with this guy who is disposing of
his various systems as a result of moving to a smaller place. This weekend,
I finally started to see the fruits of my labor.
Today I received four copy boxes with the following: 300 (plus or
minus) 8" disks with tons of programs (uncataloged at this point) and 25 or
so "spare" S100 boards including (more than one of some) the Cromemco
Dazzler, SSM video, Matrox video, SIO and PIO cards, A/D and X10 cards, a
6800-based SBC, a 300-baud modem and some memory boards (small sizes).
Additionally, I have about 20 spare copies of various BYTE magazines (list
to follow).
This week I expect several more boxes consisting of the dual 8" disk
drives (plus spares), the drive enclosure (Synergistics), the IMSAI itself
(TDL Z80 I believe), scads of original documentation, the entire run of
Micro Cornucopia, some Interface Age and Kilobaud mags, and to top it off, a
Poly 88 system. There's also a *slim* chance that he's going to throw in a
Mark-8 system.
And the best part...all for the cost of shipping. Yeah! It's
Christmas in April!
Rich
Rich Cini
Collector of classic computers
Build Master for the Altair32 Emulation Project
Web site: http://highgate.comm.sfu.ca/~rcini/classiccmp/
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