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Elec-Trol

Elec-Trol Inc. was a manufacturer of reed switches, reed and solid state relays, coils, keyboards and gauges (from the list of NSNs found at PartTarget). They appear to have been an early adopter of the idea of plate-mounted keyboard switches, with their Snap-Lock Datakeys range. They also produced printer model PR1021 that would print characters sideways.

Contents

History

Little is known about Elec-Trol. Advertisements in 1968 and 1970 give Elec-Trol’s address as 21018 Soledad Canyon Road, Saugus, California 91350. By 1985 they had moved to 26477 North Golden Valley Road, Saugus, zip code 91530.

The Procure International website briefly mentions that Elec-Trol were acquired by Hamlin (another reed manufacturer), and Hamlin were in turn acquired by Littelfuse in 2013. (Littelfuse also acquired IXYS in 2018, who in turn acquired Clare.)

Datakeys

Elec-Trol’s line of keyboard switches were called “DATAKEYS”, also described as “Snap-Lock DATAKEYS”. Details on these reed switches are all but nonexistent. They are broadly cylindrical in design (a form also taken by Clare-Pendar Series S830 and GRI Series KB amongst others) around 16.3 mm in diameter at the widest part, with a shell 30.5 mm tall. The plunger is around 12 mm tall and, in most discovered examples, has a small cruciform mount.

Elec-Trol promoted the feature of being able to plate-mount the switches, which was a fairly novel idea in 1970 when they were advertised. Around half of the switch is above the plate when so mounted. Curiously, the only keyboard known to use them, has no mounting plate, and looking at the PCB, there seems to be nothing else securing the switches (no dummy terminal or fixing screw).

The following models are known:

Model Configuration Travel Terminals Source NSN
KA1001-0004 SPST-NC double break, “with contact on arm” NSN 5930-00-160-5781
KA1002-0014 NSN 5930-00-160-5848
KA1003-0004 SPST-NO momentary, 250 V AC/DC maximum NSN 5930-00-160-5853
KA1004-0001 Single pole momentary; hollow plunger that accepts adapter Pertec keyboard
KA1005-0001 NSN 5930-01-085-4574
KA1005-0001TC204 SPST-NO momentary, 0.112″ thread NSN 5930-01-055-7852
KA1011-0017 SPST-NO momentary 5 mm Positions 1 and 3 Own collection
KA1012-0009 NSN 5930-01-013-0253
KA1016-0009 NSN 5930-01-027-2834
KA1017-0004 SPST-NO momentary Positions 1 and 2 Andrew Nelsen

KA1017-0004 is reported as having 0.27″ travel, which would give 6.9 mm, but this seems at odds with the plunger dimensions, which (from a brief video depicting the switch) would suggest 5 mm travel the same as KA1011-0017 as the plunger dimensions appear to be the same.

At least two keycap models are known, TA1-03-0-0000 (NSN 5930-01-027-9709) and TA1-04-0-0000 (NSN 5815-01-014-5692). As no markings are listed for either, they may simply be blank (as the model numbers themselves suggest, with 03 and 04 possibly designating the colours). TA60100000 (NSN 5895-00-499-8542) is given as “BAR,SPACER” and thus would seem to be a space bar keycap, of unspecified dimensions.

Two keyboards are known. Model KB1033-0000 is known only from its NSN designation of 5840-01-030-5544. There is also a Pertec keyboard, which is the source of switch model KA1004-0001 (assuming that it can be read correctly from the photos). The switches in the “Pertec” keyboard appear to be marked as having been manufactured in 1973, which matches the IC dates.

The photos below, provided by Andrew Nelsen, depict model KA1017-0004.

KA1017-0004, alternative view
KA1017-0004, alternative view

Documentation