My First Computer
IBM 1401 Mainframe Computer
Click on thumbnail to enlarge picture, Back button to return
The IBM 1401 Mainframe
IBM's 1400 series of data processing systems made a significant impact on the business world.
The 1401 mainframe, the first in the series, replaced the vacuum tube with smaller, more reliable
transistors and used a magnetic core memory. Over 12,000 of the 1401's were shipped, and its
success made a strong case for general purpose computers over specialized systems. This
mainframe replaced most Unit Record equipment at the time. Our first system had 32K of memory.
Eventually upgraded to 64K at a cost of $50,000 in 1965. Unbelievable!
IBM 1402 Card Read/Punch
One of the 1401 peripherals was the 1402 Card Read Punch unit which provided
simultaneous punched-card input and output. The reading speed was 800 cards
per minute, while the punch side could produce 250 cards per minute. Other
input/output devices for the 1401 included the 1403 "rugged and fast" printer
and the 729 and 7330 model magnetic tape storage units. (pictured below)
IBM 1403 Line Printer
The 1403 printer was a real workhorse. IBM also offered a 1404 model that had
a bill-feed unit attached for printing customer statements. Some 1403's are
still in use today. On the right is the print train for the 1403 printer.
IBM 1401 Tape Drive
Computer rooms usually had at least two tape drive units installed.
The 729 and 7330 models were available at the time.
IBM 1405 Disk Storage Unit
IBM 1406 Disk Storage Unit
IBM 1401 System Console
The function of this device was to create a log of the 1401's activities.
Also served as a nice lunch/snack counter.
Typical IBM 1401 installation
IBM 1401 Control Panel
The switches and knobs are for changing register addresses. Not a frequent occurrence.
On the lower left was a button labeled "Emergency Pull". Fortunately we never had to
utilize it, but it was tempting. The above control panel measured approx. 3' W x 4' H
A sample of SPS (Symbolic Programming System) code.