> From: Stephen Lafferty
> When I bought the Omnibus prototyping board from Douglas Electronics by
> phone a few years ago, the lady I spoke to offered to include handles
> ...
> I have not found the handles mentioned on their website but I might
> have missed it.
They do still have a few (~100) left, but you have to contact them, they are
indeed not on the Web-site; $.55 each. Grab them while they're there! :-)
Noel
Hi all,
Out of curiosity, did anybody on here subscribe to any of the newsletters published by a company called Aresco back in the late 70s and early 80s? These newsletters were VIPER (Cosmac VIP), Paper (Commodore PET), Source (Exidy Sorcerer), and Rainbow (Apple II). Aresco also published a series of books by Tom Swan titled PIPs for VIPs.
I own several issues of VIPER, but I'm still looking for copies of the others. Does anybody have these newsletters in their collection?
Matt
Hi,
some people from the "Rechenwerk Halle"
(http://9hal.ath.cx/usr/digital-ag/projekte/andere/museum/)
..a bunch of people that is interested in historical computing got an
Robotron K1840 DEC 11/780 clone lately and they try to get it running
again. (freinds of mine).
Unfortunately a thing called SKR Busadapter (Massbuss adapter) and the
entire console computer are missing.
So far as I know is the main CPU 100% compatible to the DEC original
using an UNIBUS System, PCBs are exchangeable, but the Console Computer
is not.
In The K1840 this is a K1620 Computer, the CPU is build from 8 Bit NMOS
slices (U830) and ordinary EPROMs (https://de.wikipedia.org/wiki/U830C)
using a mechanical different PCB System. The same system was used in the
K1630 PDP11-alike (see below) which had an MMU (K1620 has none).
The Main difference that's preventing unpatched OSes are the U834 Bus
interface ICs, that must be software configured before the devices can be
accessed from the QBUS-like System Bus. The U834 are containing the Bus
drivers and all needed registers for interrupt and DMA and the entire
address decoder logic needed for QBUS Systems which simplified the
interfaces somewhat.
Nevertheless of that progressive design, it was the worlds slowest PDP11..
In the K1840 ordinary TEAC FD55FV Floppies (2x) where used for the console
System to boot up the system.
So far so good (or bad).
There are a few things that I want to know now..
I know that in the original 11/780 the Console CPU was an 11/03
with some interface to load the VAX Microcode in to the main CPU.
Do you think it is possible to use an ordinary 11/23 instead?
What Floppy Controller was used in the original, I know that there was a
single 8" floppy drive in the 11/780 and don't think that the controller
was the usual RX01 or RX02 System...?
That's an article from the german magazine C't about the people which got
the K1840:
http://www.heise.de/newsticker/meldung/Rechnende-Schrankwand-Computermuseum…
That's the K1840 on the left:
http://9hal.ath.cx/usr/digital-ag/log/K1840_im_Rechenwerk.jpg
and The K1630 .. PDP11 not so "clone" on the right.
I don't think that the Tape drive was shipped with that machine, the
bulgarian original looked different so far as I remember..
Is there someone that would help out them with missing hardware/software?
Regards,
Holm
--
Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe,
Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583
www.tsht.de, info at tsht.de, Fax +49 3731 74200, Mobil: 0172 8790 741
> They still have them. They pulled the bin and put your name on it.
Great, thanks very much! Just called them up and ordered the whole shebang.
> It's about 100 (my guess) pieces
Your guess was very accurate - actually, 105!
> I already did a lifetime buy myself.
If anyone needs a _few_ (between boards I already have that need them, and
future needs, for some boards I am building, most of these are spoken for),
let me know.
Noel
> From: Joseph Lang
> How many do you want?
How many do I need, or how many do I want? :-)
I'm tempted to buy the whole bin (unless it's like a 55 gallon barrel :-),
and hold onto them for other CCTalk people who need them.
Maybe this will work: if you find them, point them out to the store people,
and tell them I'll call? Would that be the easiest thing for you?
Thanks!
Noel
I'm going to be working on my 11/730s power supply, so I'm in the
market for an ESR meter. I've seen some (older) recommendations for
the AnaTek 'Blue' and various 'Dick Smith' derivatives. However, eBay
is flooded with knockoff Mega328 based ESR/Transistor/SCR/etc. testers
all looking like:
http://www.amazon.com/DROK-Multifunction-Mega328-Transistor-Capacitor/dp/B0…
Anyone had any experience with one of these devices?
KJ
I have been using the BK Precision 879B:
http://www.testequipmentdepot.com/bk-precision/lcr/879b.htm?ref=gbase&gclid=
CKj82-uIoMgCFRNrfgodYOYOvA
It's at a completely different price point ($250-ish), and much more than an
ESR meter - but it's a bargain for a full R,C,L,Z meter. Very useful to know
not only the ESR, but the actual value of the capacitance (which for big
power supply caps could have diminished significantly over the years). It
can measure components at 100Hz, 1000Hz and 10Khz. You could not justify it
for a single power supply repair, but if you do a lot of old electronics
restoration projects, it is a precious tool to have. I couldn't live without
it now.
You can see it in action in the middle of this video here, in this case
exonerating a capacitor that I sure thought was the cause of my power
problem, but turned out to be perfectly good:
https://www.youtube.com/watch?v=lqD6xVI6qNs
Marc
======================
From: Ken Seefried <seefriek at gmail.com>
Subject: ESR Meter Recommendations
I'm going to be working on my 11/730s power supply, so I'm in the
market for an ESR meter. I've seen some (older) recommendations for
the AnaTek 'Blue' and various 'Dick Smith' derivatives. However, eBay
is flooded with knockoff Mega328 based ESR/Transistor/SCR/etc. testers
all looking like:
http://www.amazon.com/DROK-Multifunction-Mega328-Transistor-Capacitor/dp/B00
NKY3M1W/ref=sr_1_16?ie=UTF8&qid=1443561246&sr=8-16&keywords=esr+meter
Anyone had any experience with one of these devices?
KJ
=====================
This post is for Tim Shoppa.
This have seen your replies every so often on classiccmp, so you
don't seem to be totally out of touch.
If you are reading this, Alan Frisbie and I would appreciate
some help.
Allan can be reached at the address to which I sent a copy.
Jerome Fine
