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Burroughs L7000

This week I was contacted to pick up an old 60's mainframe I was told...turned out to be a Burroughs L7000 mini computer. I am going to help deliver it to the MARCH (midatlanticretro.org) museum this fall.

http://www.vintagecomputer.net/burroughs/L7000/
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Hardly a mainframe, and minicomputer is stretching it a little...
Unless it comes with a complete set of tapes the chances of getting it up and running are pretty slim. There should be a set of batteries and a DC300 tape drive and tape inside the right end cover; if that tape can be read then you might be able to bring it back to life.

If you get it up and it has at least one cassette drive, I may have some software for it.

Good luck!
 
It's a business machine from (at least) 1972; there are some details on pages 33-34 of the document here (pages 47-48 of the total pdf): http://www.bitsavers.org/pdf/auerbach/Auerbach_Guide_to_Small_Business_Computers_1972.pdf .... so if it's not a minicomputer then what would you call it?
Good question ;-)
Burrpoghs (sic ;-)) called them 'Commercial' mini-computers; they're really a category of their own with the integrated keyboard and dual printer and various (or no) peripherals.
Programmable fancy typewriter? Electronic Accounting Machine?
I didn't say it wasn't a mini-computer, just that it stretches the definition a little; definitely single-user, 8KW max, ledger cards, no video display, no disk I/O, only programmable in assembler (although there were cross-compilers that ran on the 'real' mini-computers), comm available but rarely installed, etc.

We also have a later (1982) Burroughs B-80.
That's a little closer to a mini; disk drives, video display, programmable in BASIC, COBOL etc.
 
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By itself, the workstation is not a mini or a general purpose computer. It has a card reader built in. The separate "Magnetic System" unit is I think where the storage is happening. I am not sure if multiple workstations plugged into a single L7000 or not. The L7000 looks like a *huge* A/C unit, with logic cards kind of like the PDP 8 we have at MARCH. Ultimately this is a business computer like later 70's Raytheon VT302 and Lanier Model-103. It was marketed for accountants.

Once I get back to the system and take some good pictures I will get a better "picture" of what I am dealing with. I did not find any kind of user manual, just a service record checklist doc.



Bill
 
Olivetti had something like this too. "Accounting machine" might be a better term for it:

http://www.technikum29.de/en/computer/commercial.shtm
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Well, although mini-computer is kinda stretching it, "Accounting machine" is selling them short; although they are certainly descended from the electro-mechanical and hybrid adding machines on steroids that are usually called accounting machines, they are certainly true computers in their own right, although obviously configured differently from what we think of today as "computers".

They're an interesting almost completely forgotten and ignored branch of computing with very little info or even interest out there, illustrated by the fact that even knowledegeable vintage hackers like Bill and Evan don't really know what they actually are.

Although Olivetti, NCR, Monroe and others were also major players, Burroughs was for a long time the leader in accounting machines, found in every bank branch and the offices of most medium sized businesses. While IBM was focussed on punched card batch processing machines Burroughs et al were providing equipment to do the same sort of thing in real time with direct operator input.

Originally the machines were completely mechanical except for an electric motor to drive and turn the hundreds of wheels, cams and levers that did the calculation and printing on ledger cards and journal rolls; this was the Burrough 'F' series, programmed with metal pins of different lengths and locations in exchangeable "program panels."

As solid state technology became available some of those wheels, cams and levers were replaced with transistors and core memory, and then integrated circuits; this was the Burroughs 'E' series, programmed with metal pins and wired patch board programming panels.

Then Burroughs brought out the 'L' series, programmed in 'SL3' and 'SL5' assembler (System Languages), which ranged from the original L2000 to the L9000 before the ledger cards were finally abandoned and the B80 replaced them with disk-based systems programmed in high-level languages, mostly Cobol.

About the only thing that the L series had in common other than appearance was the fact that they all had an integrated paper tape reader beside the keyboard for loading firmware and application and utility programs. Up to the L5000 the system memory was actually a small fixed disk while from the L6000 onward it consisted of 2KB memory cards; also the keyboard and PPT reader were mechanical through the 5000 and electronic after that. Although not all models did, they were mainly intended to use ledger cards and had split platen printers with a separate ledger card feeder so that the printer was actually three separate printers in a way, using a Selectric-style golf ball until the L9000 finally went to a dot-matrix printer (and sacrificed the red/black dual color capability). The ledger cards could have magnetic stripes on the back which stored account names etc. and account balances and allowed for automatic insertion and alignment (although the mechanical machines could also align the cards by punching little notches).

A full-blown L could have magnetic stripe ledger I/O on the console with or without an optional auto-feeder/stacker, and a free-standing separate auto-reader that could process a stack (probably what Bill is thinking of), up to four digital cassette drives, a paper tape and edge-punched card reader and punch, an 80 or 96 column card reader and punch, and even datacomm and a video display on the latest models. No workstations plugged into an L, it *was* the workstation, although some models could connect to a 'real' mini or mainframe.
I have a picture here of an L with all the bells and whistles; I'll try to find time to scan it.

Unfortunately there is almost no firmware or software around except for what is sometimes found in the back of the machine with the print set, or the unfortunately rare DC300 cartridge that can still be read. Ironically the older hard-disk based units are more likely to be operational while the solid-state based units are of course huge bricks without the firmware to boot them up.

There are a few others out there that I know of, although AFAIK the only one that actually works (or did at one time) is a restored L5000 at Bletchley Park.

The odds are against it, but I'll certainly cross my fingers for ya that you get it going when you get it. The most crucial part is that DC300 if there is one; if the band hasn't rotted, the oxide crumbled or stuck together etc. and if the L actually did completely and successfully dump a memory image to it the last time it was shut down, then you just might be in business. If there actually is one, then remove the cart and inspect/repair/clean it and the drive as much as possible before you turn on the machine; on power-up it will automatically try to read that cartridge and could quite possibly destroy it if it's in bad shape.

Good luck!
 
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The NCR 446 "accounting machine" shown is programmable via paper tape (program resides in core) and the Nixdorf 820 is certainly a full-blown computer.

And IBM called the plugboard-programmed 407 an "Accounting Machine", even though it probably has far less power than the Olivetti P203.

I got to witness the crossover and back between punched-card unit-record accounting systems and the real thing back in the 60's. For most of the 60's, this Chicago-area manufacturer had been doing just fine with the standard unit-record setup. (407+sorter+reproducing punch+interpreter). The CEO somehow crossed paths with an IBM Sales Engineer who told him about the wonders of computing. The CEO signed up for a 360/20 with accompanying peripherals, hired a programmer and an operator and waited for the savings to roll in. Every day, the CEO received a nice thick printout of production figures, account balances, sales, etc. that he never read.

Eventually said CEO slipped into an IBM conference and posed as representing an outfit with no information automation whatsoever. After analyzing his needs, the sales engineer recommended--you-guessed it--a standard unit-record setup.

The 360/20 and extra personnel were gone at the end of the month. Corporate America had reason to be skeptical of computerization back then. An "accounting machine" was probably perfect for many businesses.

Did you note that the entire type basket in the Olivetti was in a cassette that could be changed out? Pretty cool.
 
Hi, i am new to this forum.
My name is Jan and I am living in Sweden.

It was nice to see the old Burroughs computer, i have one too.
It is an L-8000 with the floor mounted line-printer, three tape drives (compact cassette type),
an externel paper punch and a external paper reader.

And on the right side of it, there is an DC-300 tape drive.
I have tried for many years ago to start up the machine with the tape, but no luck.
I don´t know what I have to do before I push on the "START" button or something else?

I was told the bell is ringing when it has finish loaded the tape into the memory.
Well, it was a long time ago now......

Greetings from Sweden!
Jan :)
 
Hi, i am new to this forum.
My name is Jan and I am living in Sweden.

It was nice to see the old Burroughs computer, i have one too.
It is an L-8000 with the floor mounted line-printer, three tape drives (compact cassette type),
an externel paper punch and a external paper reader.

And on the right side of it, there is an DC-300 tape drive.
I have tried for many years ago to start up the machine with the tape, but no luck.
I don´t know what I have to do before I push on the "START" button or something else?

I was told the bell is ringing when it has finish loaded the tape into the memory.
Well, it was a long time ago now......

Greetings from Sweden!
Jan :)
Hello!
I hope I'm wrong, but I'm afraid that the chances of bringing that L8000 back to life are probably not very good unless you happen to have the firmware tapes. I used to have the full set of tapes for the L5000, 8000 and 9000 but unfortunately threw them all out before I realized that there actually are some of these machines still out there, and I'd be surprised if there were still any copies of some of them anywhere today.

Check the DC300 tape mechanically: there is a good chance that the drive band inside is either broken or stretched, or the tape has unspooled; does the tape move smoothly if you turn the drive wheel by hand (in the right direction!) ? Also clean the lamp, sensor and mirror if necessary.

On the slim chance that the tape is mechanically still OK, remove the cover from the drive and clean the head and drive roller, and check that the rubber drive roller is still solid and not mushy or sticky. Does the roller spin when you turn on the machine?

Even in the unlikely event that the drive and the tape are mechanically OK there is still a good chance that the data on the tape is corrupted. The earlier model L's including Bill's L7000 used a fixed disk (2 in the L7000) for the working memory, so if the power was turned off there was no problem; when you turned it back on, it just 'booted' from the hard disk much like the kind of hard disk system we're familiar with.

However, the L8000 and 9000 had no non-volatile storage at all (other than paper tape); the working storage was a number of solid state 2KB (18x 2102 IIRC) cards. As you probably know, underneath the tape drive is a set of batteries; if the power failed these batteries were supposed to keep the machine powered long enough to dump the contents of memory to the DC300 tape, and when power was restored the system would automatically reload memory from the tape.

Unfortunately this didn't always work as often there was a mechanical problem with the tape or drive, or the batteries would die before it finished writing the tape; either way you were left with a corrupted tape and a totally dumb machine. Even though the batteries are no doubt long dead by now, do *not* power off with a tape in the drive.

The only option at this point was to reload the machine from the master paper tapes; if you are lucky these might have been left in the back of the machine with the print set, in which case you might be able to revive it. You are looking for a rather long paper or mylar tape labelled with a Burroughs number or "firmware" (as opposed to customer application program tapes); you will also need several utilities and add-ons, especially the cassette and paper tape add-ons.

Note that you don't use the external paper tape reader to load these tapes (if you have them); instead, you use the removable loader cartridge to the front left of the keyboard.

Good luck; if by chance you do get it running I do still have a number of cassette tapes with some games and utilities on them. I may also still have an L8000 DC300, but it's not very likely to still be good (if it ever was) or, if it is, that it matches your configuration.

But if you do get it running it would be fun to try to send you some programs for it over the internet... -;)

So, were there any paper or mylar tapes in the bottom of the machine and if so, how are they labelled (if at all)?

mike
 
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Thanks a lot and a BIG thanks for the informations, MikeS !

We´ll, as I say to you, it was some years ago I was trying to start up the machine.

But, back in 1990 when I bought it from my former working place, they said to me
that it had been used between 1974 until the main cord was unplugged 1987.
And they also said the battery near the DC-300 tape station was empty the last years
they used machine and it was because of that, never shut off.

But, I also get a box full of manuals, schematics (also for the printer), a lot of different
magnetic tapes and paper tapes.

The DC-300 seems to working correct, but no bell was ringin when finished.

But they told me before the start, I have to move some breakers in the right position,
then start it up with one of the DC-300-tapes, then when the bell has rang, moving the breaker back again.
That was because the backup battery was empty, they said.
And it was necessery to do that, if the power cord has been removed.

Every periferal equipment was disconnected when I got it and all of the connectors seems
to fit everywhere......a little problem.
And I have also tried the "Firmware" paper tapes in the reader, but it only gets in and out again.

Hej Pontus, then we are at least two from Sweden here, I am living in Mellerud, just
a little village between Karlstad and Gothenburg.

I also have one DataSaab in my garage.

Greetings
J-EE
 
Thanks a lot and a BIG thanks for the informations, MikeS !

We´ll, as I say to you, it was some years ago I was trying to start up the machine.

But, back in 1990 when I bought it from my former working place, they said to me
that it had been used between 1974 until the main cord was unplugged 1987.
And they also said the battery near the DC-300 tape station was empty the last years
they used machine and it was because of that, never shut off.

But, I also get a box full of manuals, schematics (also for the printer), a lot of different
magnetic tapes and paper tapes.

The DC-300 seems to working correct, but no bell was ringin when finished.

But they told me before the start, I have to move some breakers in the right position,
then start it up with one of the DC-300-tapes, then when the bell has rang, moving the breaker back again.
That was because the backup battery was empty, they said.
And it was necessery to do that, if the power cord has been removed.

Every periferal equipment was disconnected when I got it and all of the connectors seems
to fit everywhere......a little problem.
And I have also tried the "Firmware" paper tapes in the reader, but it only gets in and out again.

Hej Pontus, then we are at least two from Sweden here, I am living in Mellerud, just
a little village between Karlstad and Gothenburg.

I also have one DataSaab in my garage.

Greetings
J-EE
Sounds like you might be lucky and get that baby up again after all; if/when you decide to give it another try I'd really be interested to follow your progress.

Yes, I think there is a switch inside one of the panels (but I don't remember where) which has to be turned off to load the DC300.

IIRC to load paper tapes you thread the tape, press PK2 (?), turn on the loader switch, and when it runs out turn off the loader and press the reset button (in a recessed hole to the left of where your knee would be); you'll need to load several tapes in sequence and probably also "gen" a system register (although I think you can do that from cassette).

Assuming you have the print set (a large binder with schematics, wire lists, etc.) you should be able to figure out where the peripherals plug in. Failing that, if you look at the connectors you'll probably find that not all pins are used and you might be able to match plugs and sockets that way.

On the off chance that you bring it up and also have the memory modify tape, I do still have the SL-5 programming manuals for those machines; also some ribbons & MMR ledger cards...

I know of a few series L machines in existence but AFAIK none (except perhaps an L5000 at Bletchley) are actually running; yours would be a rarity indeed if you get it going, especially since it is exceptionally loaded with 3 cassettes, a line printer *and* PPT I/O.

Good luck!
 
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Hej Pontus, then we are at least two from Sweden here, I am living in Mellerud, just
a little village between Karlstad and Gothenburg.

We are a few more :) Zeela and Carlsson are also swedish.

I also have one DataSaab in my garage.

Ooh, which one? Datasaab made really nice machine, the little I've read about them has been very neat.
 
Thank you for your help MikeS!

Your info is very valuable for me and I gonna save it until the next attempt.
And of course, I will let you know, when I doing the next try.

Maybe it´s a little unusual for now, the most of the Burroughs are maybe in the computer heaven...

Right now it´s parked in my garage and there´s a lot of other things filling up the space around it, so i have to wait until I get rid of all other different things around it.
But then......:)

At the factory who owns it before, they used it for sending out all the bills to the customers and
also handle the accounts for all of the employees (300), and for the book keeping.

The women who used it everyday back then, was sitting inside a little airconditioned and sound insulated room with windows all around. She also used ear plugs.
It produced a lot of heat and a lot of noise too.....

I didn´t know there was more people from Sweden here, but I am also an newbie here.

My Datasaab is from around 1975 and it was used on the same factory only for
verifications to the book keeping.
But 1981 they went over to the PC systems instead.

I don´t know what model it is, I am a little curious too.
But I have never seen it on a picture either.

Sorry, i don´t have a photo of it, it is in the garage too.

It´s a small but heavy system unit, approx. 80 cm. height, 40cm. width and 60cm. deep.
A separate heavy electromechanic white keyboard and a separate small monitor in sheet metal.
Maybe 12 inches with amber lightning.
That´s the whole system.

The most of it, is colored light blue with some of it white or grey.

On the front of the system unit is a magnetic tape r/w (Compact Cassette).
And it works fine, at least at the last time i checked it.

Greetings!
J-EE
 
My Datasaab is from around 1975 and it was used on the same factory only for
verifications to the book keeping.
But 1981 they went over to the PC systems instead.

I don´t know what model it is, I am a little curious too.
But I have never seen it on a picture either.

Sorry, i don´t have a photo of it, it is in the garage too.

It´s a small but heavy system unit, approx. 80 cm. height, 40cm. width and 60cm. deep.
A separate heavy electromechanic white keyboard and a separate small monitor in sheet metal.
Maybe 12 inches with amber lightning.
That´s the whole system.

The most of it, is colored light blue with some of it white or grey.

On the front of the system unit is a magnetic tape r/w (Compact Cassette).
And it works fine, at least at the last time i checked it.

Greetings!
J-EE

Perhaps it is a D5 or D15. But since you say it is blue I'm thinking it might have been after datasaab was bought by Ericsson, they painted some of their systems blue, but if you say 1975 it is a little to early for that (I think, information about datasaab is sparse).

http://www.datasaab.se/Bildarkiv/D530/d530.htm
 
Hi, i am new to this forum. My name is Ilshat. I am from Russia.
I found this forum on the Internet.
now we are creating a museum of computer technologies.
in the early ' 70s, we had Burroughs L Series.
They were used to transmit information from oil companies to Moscow, the center of the oil industry.
Now it is impossible to find information about the cooperation between Burroughs and the USSR on the Internet.
You probably have some information about this relationship.
We would be very happy if you can provide information (photos, documents, advertising booklets of the time, etc.).
It would help our museum a lot. I attach a unique photo from 1974, which shows a woman working on a series of Burroghws L. It was located in the city of Almetyevsk - in the computer center of the company "Tatneft". I talked to her - she says that the reports were transmitted through this computer to Moscow - to the Ministry of Oil Industry of the USSR.
Sorry for my Enlglish :-(
Best, Ilshat.

Burroughs KIVC.jpeg
 
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