Clare-Pendar Series S830
Clare-Pendar Series S830 is a tall reed switch series. The shell is cylindrical, vaguely similar to George Risk KB reed switches. S830 supports momentary and alternate action. The rated lifetime in 1971 was 100 million cycles at logic levels (i.e. low voltage and current). These have been found Clare-Pendar–branded, although in 1971 they were advertised by parent company C. P. Clare.
S830 dates back at least as far as 1971. Manufacture goes back at least as far as early 1972. S83010 switches sold on eBay appear to be made in 1985 (stamped “G.I. 3W720 8536 S83010”).
S830 switches sold by STRONIC in France look identical to those in the ca. 1972 calculator keypad, but “ASM. MEXICO” has been added to the mould below the CAGE number. These do not bear either a model number or a date code.
- Unidentified keyboard, mostly S820 but the Upper Case Alpha key uses S832-10B9 alternate action (switches dated 1971)
- Monroe or Compucorp calculator keyboard, similar to the keyboard of a model 1860 or 1880 (switches dated 1972)
- C. P. Clare Model S830 advertisement, Electromechanical Design, Vol. 15 No. 5, May 1971 (painfully extracted from the Internet Archive)
- S830 announcement, Electronics, Vol. 44 No. 9, April 26 1971, page 84 (scanned by or for WorldRadioHistory.com)
- S830 entry, Deskthority wiki (prior notes)
- Series S820, a more typical-looking data entry reed switch series