Return to Bhushan Mohan

IBM 1401 Series in India

Information from Bhushan Mohan

Reformatted from questions/answers by Robert Garner

Hi Robert,
Thanks for your mail.
It has really been my pleasure to contribute in a little way to the last operational 1401s.

Right from early 60s till mid or rather late 70s, 1401s were the mainstay of commercial computing in India.

In June 78, although IBM, due to some regulatory reasons, stopped its operations in India, the 1401s continued to be extensively used and well supported. Subsequently a public sector company took up a project of rejuvenating the 1401 CPU with TTL logic, solid state memory expanded to 64k and clock speed improved by almost 3 times to 4 microseconds. Assembler and key utilities like Sort 7 were also tweaked to exploit the enhanced features of the system, called the 1401R.

However, these improved systems could not win against the onslaught of the mini and micro systems which started coming in the early 80s to India and not more than half a dozen systems were upgraded. Gradually 1401s started getting discontinued from operations from mid 80s although some with a few government organizations continued to be used almost till the end 80s. I may not know which organisation discontinued the last, but surely Indian Railways (one of the biggest users of 1401s) continued to use many of them till 1989. There could be some users who might have kept them operational even till very early 90s.

Most of the 1401s were used for very routine accounting and financial applications. Almost all of them were tape-based systems, but a few customers also had 1311 disk drives. Sort64 was a commonly used utility by the disk customers. Indian Railways had one of its systems dedicated for managing the rolling stock inventory. Inputs from various field cross-over locations across the country came through dedicated teleprinters in the form of paper tape. The 1401 system had a 1011 paper tape reader as a key input device.

Another customer, Indian Airlines, had two 1401 systems dedicated to support the airline reservation system. Both the systems had five 1311 disk drives along with four tape drives. Their mission critical reservation support application used to run during night time (far more critical than a payroll). Another 1401 system with one of the educational institutes was used as an input/output to a large 7044 system. And we did have some (very few) 1401H customers. (1401H were purely card based systems: 1401, 1406, 1402 and 1403, but no tape drives.)

Most of the 1401s operated round the clock, and were housed in properly designed air conditioned centers. Customer Engineers supporting 1401 systems were assigned to work in predefined shifts to ensure highest levels of services to the customers. A proper record was kept of the availability and downtime of the systems. The target was to have monthly availability above 98%. Preventive maintenance on a weekly / fortnightly basis was scheduled. Since the dust levels are very high in India, we normally used to do 1402 reader clutch cleaning and tape drive transport monitoring practically on a monthly basis. All other activities were carried out as per the PM schedule of each machine/unit. Our 1401 teams were always under the highest pressures.

There is an interesting prequel to the rejuvenation of 1401s. Somewhere around 1976, IBM in India decided to upgrade its ACA-based Unit Record m/cs; i.e. 407/447. A totally new accounting machine (named 4XX) was designed using solid state electronics (mainly supported with 7400 series integrated circuits) and an integrated card reader (based on 2501 card reader) and an integrated printer (based on 1443 printer). The wired control panel for the user "programming" was kept the same and compatible with old 407/447 accounting machines. These Unit Record systems were very popular in small and medium organisations and continued to be used till mid 80s.

Although I tried but could not succeed in retrieving any old documentation on either 1401R or the redesigned 4XX accounting machine, but shall surely share if I succeed in laying my hands on them.

Very nostalgic
Cheers and best wishes