Saturday, September 21, 2019

Another version of the DSS620 from Nixdorf & Power Supply

Dominique shared these with me today, saying he found these pictures a long time ago. finds no matches.
To see the power supply current/recent auction, open this post.

Monday, September 9, 2019

Building a Power Supply for a DG Nova / DSS-116 from "scratch"

To keep costs down, I'm going to attempt to start with a modern ATX power supply (and likely 2 or 3 laptop power supplies), and attempt to adapt it/them, simply because I have such a surplus of all of these.

The DG Nova power supply apparently consists of these voltages:

+11v (Front panel lamps only?)
-15v (Optional for customers only?  What does that mean?)
+/-15v Oscilating at 60hz/50hz from the source AC power line input, 30v peak-to-peak
+5V OK   7-8vdc?
PWR FAIL 3-4vdc?
MEM OK   3-4vdc?

Here's some golden information in the 1969 DG Nova Maintence Manual on power signals.
And yet more, somewhat differing information on some/all of the same power supply outputs, in the Technical Manual for the Nova 800 Volume I, page 4-47 (starts at the bottom of 4-46 and goes all the way through 4-50.  Almost all of this seems relevant for creating a power supply from scratch)
The "P2" "lower power supply" connector on this backplane is mapping out as follows:

Well, it ALL depends on how you number the pins on this connector. Are all of the even pins on one side, where all the odd pins are on the other?  Like all of the board backplane connectors? NO.  Turns out that there's inconsistency with the numbering scheme on the backplane.  Some connectors are the all-even side and all-odd side, and others are sequential each side, and then back to the top on the other side where the sequence continues...Talk about confusing!

P2, the main (lower) power connector to the backplane, where the resistor board connects the power supply to the backplane:
01-05 +5v 
06    A9  on Slots 2-12 RINH
07    A11 on Slots 2-12 RINH
08    A15 on Slots 2-12 RINH
09    A13 on Slots 2-12 RINH
10    A19 on Slots 2-12 RINH
11    A24 on Slots 2-12 RINH
12    A28 on Slots 2-12 RINH
13    A25 on Slots 2-12 RINH

14    A27 on Slots 2-12 RINH

15    A29 on Slots 2-12 RINH

16    A23 on Slots 2-12 RINH

17    A21 on Slots 2-12 RINH

18    A17 on Slots 2-12 RINH

19    A18 on Slots 2-12 RINH

20    A7  on Slots 2-12 RINH
21    A5  on Slots 2-12 RINH
22&48 +15v to A10, B46, B84 on Slots 2-12  )
23    POWER FAIL to A5 on Slot 1
24    MEM OK to A9 on Slot 1
25    +/-60Hz AC to B6 on slot 3 
26    Lamp Ground (to P1 pin 40)
27-31 +5v
32-47 Ground
48&22 +15v to A10, B46, B84 on Slots 2-12   
49    -15v "available as a customer option..."
50    +5v OK to A8 on Slot 1 (so is this high or low in an OK state?)
51    -5v unreg. to A6, B81 on Slots 2-9   
52    +15v unreg. LAMP (to P1 pin 33)

There's nothing on the backplane other than a "1" by pin 1, so unless you figure it out through trial and error, you'd never know which way the pins are numbered!  Thus my numbered image above.

From my video below, I mention missing power supply connector "resistor" boards also.

I MAY have found one of those here on bitsavers...
And then, for schematics for these power supplies, first, from my own site right here, I've posted 2 books full of schematics, and here's 12 schematic excerpts that may be relevant  (warning, 11Mb file)

And more continued below.....

Sunday, September 8, 2019

14" Magnetic Plate * Hard Disk Drive Platter Nixdorf Computer * VINTAGE * Rarity

The original eBay title in German is:
14" Magnetplatte • Hard Disk Drive Platter Nixdorf Computer • Vintage • Rarität

So, what does this disk have on it?  Could it be Entrex system OS of information?  What does that handwritten label say, exactly? I see that it is similar to the disk packs that Dominique has on his system, which are taken by the Diablo Model 40 disk drive.

Original eBay Auction                                      eBay Auction Archive
Google Translation:
Uninstall my private computer museum piece by piece .....

Stop by, there are still rarities until the year 1974

They offer a rarity of Nixdorf computer.
It is a 1-fold magnetic disk (platter) with a capacity of about 5 MB.

Condition see pictures

Due to the current case law on product liability and the new provision of the law of obligations in the Civil Code, I am obliged to point out that the item is sold as used to the exclusion of any warranty private by me. Please ask your questions before buying. The item is sold "as is" by Privat. This means: "With the purchase, you expressly agree to waive the statutory warranty and warranty for second-hand goods completely." Please do not buy the item if you disagree with these rules.

private sale
No warranty, no warranty, no return

Insured shipping

Original German:
Löse mein privates Computermuseum Stück für Stück auf.....

Schauen Sie vorbei, es kommen noch Raritäten bis ins Jahr 1974

Sie bieten auf eine Rarität von Nixdorf Computer.
Es ist eine 1-fach Magnetplatte ( Platter ) mit einer Kapazität von ca. 5 MB.

Zustand siehe Bilder

Aufgrund der aktuellen Rechtsprechung zur Produkthaftung und der Neuregelung des Schuldrechts im BGB bin ich gehalten, Sie darauf hinzuweisen, dass der Artikel als gebraucht unter Ausschluss jeglicher Gewährleistung von mir Privat verkauft wird. Bitte stellen Sie Ihre Fragen vor dem Kauf. Der Artikel wird "so wie er ist" von Privat verkauft. Dies bedeutet: "Mit dem Kauf erklären Sie sich ausdrücklich damit einverstanden, auf die Ihnen gesetzlich zustehende Garantie und Gewährleistung bei Gebrauchtwaren völlig zu verzichten." Kaufen Sie den Artikel bitte nicht, wenn Sie mit diesen Regeln nicht einverstanden sind.

Keine Garantie, keine Gewährleistung, keine Rücknahme 

Versicherter Versand

Wednesday, September 4, 2019

Nixdorf Dumb Terminal 1970's and 1979 Nixdorf modem (Bray, Wicklow, Ireland)


My closer photo analysis leads me to believe that this is indeed
which means that the person who posted this ad 3 years ago is likely the one who bought it from Matteo on eBay in 2008-2009 

From seller PSFan
Member since: November 22, 2012
Location:         Baldonnell, Dublin
Sold items  
Active items



I'm selling my beloved Nixdorf Terminal and modem. The terminal came all the way from Italy - Rome to be precise - where it was found in a Barn! I've owned it for 7 years. It cost around €110 alone to ship at the time!

It powers on and the fan kicks up, but the display is garbled. Who knows, it may be a loose connection somewhere or a chip issue. Not bad given it's age and history I guess! It's time to pass this on to someone who can investigate it further. As is, it's a fascinating slice of history being as it is over 40 years old.

The Modem came from the U.S., and was bought around the same time. It was manufactured in 1979. These are unique items that I'm selling reasonably priced as I'd like the space they're taking up. Needless to say, these are for collection, Bray area.

Thanks for looking!

I am hoping that we can find the seller of this, since the ad was withdrawn 3 years ago, but the seller still seems somewhat active.  We will try.  If you are the owner of this terminal, please contact us here!  Thank you!


Sunday, August 25, 2019

Vintage Computer ENTREX NIXDORF SIEMENS OLD Rare Collectible 16-bit Front Panel

I was first notified of this auction on July 20, 2019.  This was being sold by Dick DuBois, a former employee of Entrex/Nixdorf during the reign of this system.  So, he would certainly be able to verify its origin.

He sold it on Aug 25, 2019 , 1:05AM (36 days later) for his ask of $295 (but not to me, sorry).  Congrats, Dick, and I'd love to hear from the person who bought it, to hear the story behind its meaning to them, and how they may intend to use it.  So, if you're reading this, please click the contact tab at the top of my website here, and drop me an email!

My novice commentary: This appears to be most similar to a "half-height" DCC D-116 front panel, but clearly different, in that it is lacking all branding and model markings, the key/lock tumbler barrel switch and/or hole for such.  (more differences noted by me at the bottom of this post)

It does indeed look very utilitarian, as if it was truly intended solely for testing, and never to be placed with a customer.  Dick confirms this in his auction description, below.

But I'd love to get the feedback of someone more knowledgeable on this system.  From my Digital Computer Controls - D-116 16-Bit Computer Handbook, here's the comparison:
Original eBay Auction Sold                       eBay Auction Archive
Very Rare Vintage Collectible Computer 16 Bit Front Panel
This panel measures 19" X 5"
and was mounted in the front of the
CPU chassis during troubleshooting.
It was not usually left on site.
We are not sure if it still works
so we are selling it as - no returns
A real nice piece of vintage computer history.
Nice collector's item.

Sunday, August 4, 2019

Nixdorf 480 80 Series Operations Manual

I acquired this from

While it seems to be from 1979-1980, and the Data/Scope Keystation style has changed to the upgraded style (and they even call it a Data/Terminal Keystation now), my hope is the system had changed little else since earlier versions...or so we can hope!
Anyway, here is the entire manual, scanned.  Enjoy!

**BONUS:  I even scanned the inserted notes and extra printed pages that were in this manual, in the exact location between the exact pages that they were found, to preserve the context, in case they were significant there.  So, when you see things that don't look like the manual right in the middle, now you know why...

WARNING:  This pdf is 146Mb in size.  So, in order not to choke your browser, you may choose to right-click the link and choose "download", rather than just click the link've been warned...

Monday, July 1, 2019

Vintage 1972 Core Memory Motherboard - Digital Computer Controls - Collectible

Original eBay Auction                       eBay Auction Archive


Vintage 1972 Core Memory - Motherboard Digital Computer Controls - Collectible
The title says it all. The board is 15" x 15". Would look great hanging on your wall. All that power...
BTW, as far as I know, this board does not work, so...Non-working. It is presented for the Art that it Is. 
Component side has two areas of slight oxidation. See photos. I didn't attempt to clean on the off chance that I'd do something I shouldn't. Otherwise board is very clean.

Sunday, June 9, 2019

key tronic corp. Keyboard 065-01149- on Entrex Data/Scope

Now that we can finally see more close up what the internal workings of an Entrex Data/Scope keyboard look like, we can see the manufacture and at least one of the model numbers:



And then the stamped 003 after that.  Not sure how significant that is, but since it's stamped and the other numbers are etched directly into the board, it seems like those last 3 digits can change easily, where the previous digits are the true model number "set in stone" for this board.

Let's see what insights the experts over on have on this...

Thursday, June 6, 2019

Entrex Data/Scope in Atari 400 800 XL XE catalog - ZiMAG

I came across this advertisement for ZiMAG magnetic media (clearly quite vintage early 80s) at 

And on PAGE 10 (or 11, depending on if you count the front cover as page 1), we clearly see an Entrex Data/Scope!  What's that doing in there?  Well...let's take a closer look...
Firstly, the chassis cover is painted this very nice dark charcoal color, which matches the advertisement colors very nicely.  I've never seen one in charcoal before, only white and off-white (or yellowed with age).  I've seen red, but then again, it could be for exactly the same "display only" reason that I suspect here.  Here's why I say this:

It sure looks like the blue and white keys have been all painted black, and that a few red and black keys have been moved around a bit.  (Note that only a few black keys show the white lettering, but most are just plain black).  
For example, the HELP! key should be on the top of the right (atop the right vertical row), but instead, it is on the extreme left middle of the main key group, which should be a red RESET key instead of the black HELP! key.
It sure looks to me like this keyboard has been modified for the aesthetics of the advertisement, rather than functionality.  Still, VERY nice job...from first glance, it is quite an attractive piece in this context.

What I'm more interested in, is the code on the screen.  Looks like standard line basic to me...was it really displayed on this Entrex, or superimposed there?It appears a bit too close to the top edge to be on a CRT, and they were all green, as far as I know, not yellow(ish).  BUT, who knows?