Wanted list for Micro Switch

Contents

• Parts
• Literature
• Charts
  • SW PCBs
  • SW component charts
    • SW ICs
    • SW springs
    • SW plungers
  • 2SW charts
  • SD electrical data
  • 2SD keycaps
  • 1001SD remaining charts
  • SC Series
  • CT Series
  • PB Series

Parts

• SW switch mounting frame: as SW switches are not self-contained, a mounting frame is required in order to hold switches for force and behavioural testing
• 1SW300 Series switches (known but not understood or observed)
• SW secretarial shift, to see how it works (this may be 1SW300)
• SD secretarial shift and if possible the control rod holder: for measurements for accurate diagrams of how SD secretarial shift works
• KB Series reed types not in collection (in particular solder terminal types, alternate action and tactile)

Literature

• RW Series keyboard catalogues
• KB reed switch catalogues (the reed types are not documented alongside the non-reed KB switches)
• SW Series switch listings
• SD Series switch listings
• SC Series catalogues
• CT Series catalogues

Charts

SW PCBs

• PCB SW-11178 from model 51SW12-1 (this has no 2-of-N grid)

SW component charts

Inspection of the SW charts has yielded the following list of interesting components. These charts should allow the specifications of the various SW and SN models to be reconstructed, specifically the sensor types and switch weightings:

SW ICs

Multiple sensor types appear to exist per behaviour. Additionally, SW Series was converted to using SD Series sensors, even though the two types have different pin spacings.

With SD Series there are also a variety of non-standard sensor types (a non-standard letter is marked on the sensor, and the switch identification code is prefixed with this same letter), but so far, no means to identify the components. The “A” charts for 1001SD might help clarify this.

SW springs

Confusingly, my calculations put SW-10006 at 2.5 oz, but nominally the standard weight is 3 oz.

SW plungers

There are a surprisingly large number of plunger types! Seeing the illustrations in the charts might help understand the differences between switch models.

2SW charts

There are going to be too many 2SW charts to gather up, but a handful could be interesting. There does not seem to be a part number structure as there is with CT Series.

SD electrical data

The following documents describing the various SD Series Hall sensors would help people repair and modify old Micro Switch keyboards:

2SD keycaps

Additional 2SD charts to get a more complete understanding of the range of options.

1001SD remaining charts

A few 1001SD charts are still missing:

• M: 13
• A: 3, 5, 7, 9–11

SC Series

Micro Switch part SC10075 appears to be an actuator assembly from an SC Series keyboard. Having the chart for this would be interesting. This is an unusual part in that it takes some unidentified keycap instead of the normal CT Series keycaps that ST and SC keyboards have been observed to use. No examples of SC10075 have been seen in the wild.

Additional SC charts may contain useful details such as the different weightings of plunger module (actuator).

CT Series

More CT Series charts, to help understand the part number system. Some of these will be keycaps (e.g. 3CT*) but there will also be part numbers for the plunger modules.

PB Series

Any data on the keyboard switches in the range 1PB870 to 1PB879, in particular to help differentiate types that appear to be the same but have different catalogue listings (e.g. 1PB871 and 1PB877).