| +Home | Museum | Exhibit | Articles |
Old Calculator Web Museum Documentation Archive
Friden EC-132 Temporary Service Manual, August, 1965
This is the Temporary Service Manual for the Friden EC-132 Electronic Calculator, published August 1, 1965. This document is called the "Temporary" Service Manual because it was produced very early on in the life of the Friden 132, and presumably a more complete Service Manual was produced at some later point in time. As yet, an updated service manual for the EC-132 has not been found, but it could be lurking amongst the cache of documentation in the museum's collection still awaiting review and cataloging.
The temporary service manual was published in order to get service information out into the field service force as quickly as possible. With the EC-132 introduced to the sales force in early April of 1965, and machines likely in the hands of customers by the summer of that year, there was a need for service people to have some documentation to refer to in the event they were called to a site with one of the new EC-132s that needed service work.
This preliminary document addressed the basic requirements for the field force to be able to identify and repair problems with these machines by explaining the differences between it and the EC-130 (mainly the logic for the added square root function), and going into some detail as to how the changes to the logic were implemented. The document assumes that the reader has an intimate understanding of the logic of the EC-130 calculator.
The document is intended to be used in conjunction with the EC-132 MDD (Master Design Documentation) Computer Printout, which provides information about the location of the various gates and flip flops, down to the component level on the circuit boards. I am currently searching through the cache of documentation looking for any example of the MDD for the EC-132, and if found, I will scan and post it here).
It is not yet clear if this document applies to the four-counter version of the EC-132 (Serial Numbers below 3902), or the three-counter version. It is likely safe to assume that it for the four-counter version, as the three-counter version of the EC-132 was introduced in the late part of '65, and this document was published before then. The logic changes made to the EC-130 to implement the square root function were likely applicable equally to the three- and four-counter versions of the EC-132, since the logic changes are not necessarily specific to the counters, but rather to the logic that governs their operation. If a MDD Computer Printout can be found for both the three- and four-counter versions of the EC-132, then is should be possible to match this service document up with the MDDs to determine which version of the EC-132 this document is most applicable to.
It is requested that this document not be redistributed without the watermark indicating its source.