How Old Is My Line Printer?

Since 1989, the serial numbers on the Tally line printers have been configured so that you can tell the year the printer was manufactured, the month in which the printer was manufactured and the model number of the printer. This information is of great use when we assess a printer's readiness for upgrades.

A typical serial number for a Tally line printer is D67A20548 and from this we can decode that the printer is a MT691 built in January 1993.

How do we decode that?

The first letter of the serial number, in this case a D, represents the last digit of the year of manufacture. The first letter is incremented each year with the starting year of 1989 or 2000. So from the following table, D representing 2, yields the year of manufacture as 1992 or 2003. We know that we stopped making the MT691 printers in the 1990s so the year of manufacture is 1992.

The next two numbers represent the model number of the printer but note that these are not necessarily what you might expect. From the following table we deduce that 67 could be a MT691, T6092, T6140 or T6141 printer. To finally determine the printer as a MT691 would need us to eyeball the printer.

And finally, the second letter denotes the month of manufacture and from the following table we deduce that the month of manufacture was January.

So now you can deduce for yourself just when your printer was built!