My First Computer

 

IBM 1401 Mainframe Computer

(circa 1963)

 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!

 



1402CardReader.jpg (76196 bytes)

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)

 

 

1403Printer.jpg (71917 bytes)                    1403printmech.jpg (72012 bytes)

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.

 

 

1401TapeUnit.jpg (44739 bytes)   

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.

 

 

14011405storage.jpg (75974 bytes)                 1401ibm1405storage.jpg (66924 bytes)

IBM 1405 Disk Storage Unit

 

 

 1406DiskStorage.jpg (56397 bytes)

IBM 1406 Disk Storage Unit

 

 

1407Console.jpg (53394 bytes)

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.

 

 

1401TheOldDays.gif (71149 bytes)

Typical IBM 1401 installation

 

1401ControlPan.jpg (94420 bytes)

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

 

 

1401sps(symbolicprogrammingsamplecode.jpg (119830 bytes)

A sample of SPS (Symbolic Programming System) code.