Magnetic drum computers of the 1950s

We were cataloging text materials recently at the Computer History Museum and came across documents describing some early computers from the 1950s. These machines were being sold during the time when “small” machines used magnetic drums as memory. A few years later this type of memory was replaced in the market with core memories.

The Elecom 120 computer was sold by Underwood. Its magnetic drum memory contained storage for 1000 words of memory with an access time of 20 milliseconds. Programs for the machine were written in machine language. The Elecom could also attach paper tape and magnetic tape devices.

Another machine from the same era was the National Cash Register model 102-D. It was similar to the Elecom and also used drum memory.

National Cash Register 102-D computer

DEC archiving project at the Computer History Museum

The Computer History Museum (Mountain View CA) recently completed a large archiving project that consisted mostly of documents and photos donated to the museum by the Digital Equipment Corporation (DEC), which was headquartered in Boston and existed as a company from about 1950 through about 1998. DEC was one of the computer giants of its day, second only to IBM.

Dick and Anna participated in the project for its entire duration, which was about two years. The project contributed 20,000 new items to the museum’s database.

Table set up to do archiving in the Computer History Museum collection
Table set up to do archiving in the Computer History Museum collection
One of the photographs from the DEC collection: participants in a sales training class in the 1980s
One of the photographs from the DEC collection: participants in a sales training class in the 1980s

Anker-Werke banking machine

One of the more interesting objects in the Computer History Museum’s SAP collection is a banking machine made by Anker-Werke, a German company with an interesting history that used to be headquartered in Bielefeld, North-Rhine Westphalia.

Anker-Werke logo
Anker-Werke logo

The company was founded in 1876 by Carl Schmidt as a knitting machine factory. Besides knitting machines [Nähmaschinen] the company has also made cash registers [Registrierkassen], ticket and reservation machines [Buchungsmaschinen], small motorcycles [Kleinmotorräder], and bicycles [Fahrräder].

Banking machine
Banking machine

After World War II Anker-Werke focused exclusively on office machines. In 1976 the company was liquidated. Part of the business was sold to the British firm Thomas Tilling, and the rest now belongs to technology giant Oracle.

IBM 7094, an ancient mainframe

In 2014, the Computer History Museum got a large donation from Paul Pierce. The donated collection included an IBM 650, IBM 709, and an IBM 7094.

When I first graduated from UCLA, the first machine I was paid to write software for was the IBM 7094. At the time the language being used to program it was Fortran II, since the 7094 was a “scientific” machine. IBM began selling it in 1962 and it used transistors instead of vacuum tubes. When it was new, such a machine cost about $3,000,000.

The image above is part of a donated IBM 7094 sitting in the Computer History Museum warehouse where Anna and I volunteer to help catalog and curate artifacts.

IBM 1401, an old friend

After we got trained on how to use a pallet jack (in the Computer History Museum warehouse), we could begin cataloging some of the “big stuff” in the collection.

Dick operating a pallet jack at the Computer History Museum warehouse
Dick operating a pallet jack at the Computer History Museum warehouse

I was happy that one of the first big objects we worked on was an IBM 1401 CPU. This was the first machine I worked on when I went through my new employee training at Service Bureau Corporation in 1965. When we weighed and measured it, we found that it tipped the scales at over 2000 pounds! It was so heavy we could just barely move it around with a pallet jack. And this was only part of a complete 1401 system.

According to an IBM website, this machine originally was rented for $2500+ per month, and there were once over 10,000 of them in service. IBM stopped selling the 1401 in 1971.

At Service Bureau we used our 1401 mostly to do card-to-tape operations so we could process the tape on a 7094, and to print data the 7094 wrote on tape when our batch job produced output. Our 1401 had 8K of memory. I did learn to program the 1401 in Autocoder (the 1401 Assembler), but I only wrote a few programs for it.

The Computer History Museum has restored another 1401 to a running state. It took several years to get it working.