The IBM 704 and 709 Systems

This is of one of the four IBM 704's that were used during the latter part of the 1950s. The first machine showed up in 1956. During their tenure, memory capacity grew as IBM learned how to make core memory. Initially, the 704 had 4K, then 8K then 32K words. A word was 36 bits. The tape handlers on the left in the picture were IBM 727s, among the first drives using vacuum columns and tapes made from plastic which was coated with an iron oxide for magnetic storage. These tape drives and, more importantly, the tapes themselves stimulated the acceptance of half-inch-wide, 7-track tape, with recording densities of 200 cpi, and speeds of approximately 60 inches per second (ips) as an industry standard. Additional capacities were added over the years: 556, and 800 cpi, and speeds of 120 ips or more.

On the left of the console is the most commonly used input device; a punched card reader - 150 cards per minute (The other input devices - much less used were tape and keying in using the large toggle switches at the bottom of the console.) The console also displayed the contents of the accumulator, the multiplier-quotient, and several other registers. The 704 was one of the first computers in the IBM stable to use index registers, seen at the top of the console.

The photo is not detailed enough to identify the person seen next to a tape drive.

Just on the right of the console, is the IBM 780 direct-view display and in the background, can be seen the Beattie-Coleman friction driven camera mounted on the IBM 740. Our attempts to use this equipment led among other efforts to all the graphics subsequently flooding the world.

On the extreme right of the picture is the then-ubiquitous IBM line printer, a modified 407 accounting machine printer, which ran at 150 lines per minute. The printers were able to print lines of up to 132 characters on 17-inch-wide paper.
Figure 1: Core Memory
This view shows one of the first Core Memories, but the circuitry was driven by tubes, or as the British would say, valves. Each box contained up to 16K words (36 bit) of memory.
Figure 2: The IBM 704 Operator's console
Figure 3: The IBM 709 Console
The 704 and 709 consoles were generally similar. In the background Tad Kishi is loading a tape on an IBM 727 tape handler. Subsequently, IBM introduced the 729 series of tape handlers. They were markedly better than the 727s. The person by the card reader is Ruth Kilby.

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