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Alps KCC Series



KCC Series was Alps’s standard data entry keyboard switch in the early 1980s. The date of introduction is not known; the design can be traced back as far as 1978 and 1979 advertisements in JEE (Journal of Electronic Engineering) depicting identical types AKC2C and AKC2N. Somewhere around the start of the 1980s the new K naming scheme was introduced and these switches became KCC Series. (How type SCH fits into this is increasingly unclear.)

Around 1983, the design of the switch was rearranged to meet DIN compliance, resulting in KCL Series (followed a year or so later by KCM Series). Nonetheless, KCC series remained in production at least as late as 1987 (the production date of a large batch of SKCCAF002A), and the use of short switchplates suggests that production extended to 1989 or later.

The earlier names “AKC2C” and “AKC2N” suggest that they were the follow-on type to AKC coil spring contact switches, which KCC supplanted in desktop calculators. The earliest known mention of the replacement series name of KCC is from 1981, in the Wizard of ALPS advertisement, along with a number of other K-series names.

The series name changed again around 1985, splitting into SKCC switches and KFCC keyboards. KFCC can be seen in the leaflet for an Alps AKB-3420 keyboard dating to around 1988 (based on the IC dates).

An Alps advertisement in JEE somewhere within issues 205–210 (1984) for KCL Series and KCC Series lists the following switch types within KCC Series:

Available operating forces at that time appear to be 60 gf and 90 gf. (This is based on the tiny amount that Google Books allows anyone to see, in very low resolution.)


From the Ambit catalogues and JEE advertisements:

Operating force 90±25 g (Ambit catalogues)
60 gf, 90 gf (JEE advertisement)
Travel 3.5±0.5 mm
Contact resistance 5 Ω maximum
Rated load 100 mA at 12 V DC
Lifetime 5 million cycles (Ambit catalogues)
10 million cycles (JEE advertisement)


The Yamaha QX1 used the short green switches. The service manual—dated as March 1985—gives these switches as KCC10903, while Eleport Corp in Japan were at one time selling them as SKCCBK0001 (sadly with an unreadable production date stamp). Eleport’s appear to have been the newer design, the same as the SKCCBJ switches that were sold with short switchplates.

Type Colour KCC model SKCC model Slider height
Momentary, higher weight Cream SKCCBJ Short
Momentary, lower weight Green KCC10903 SKCCBK
Momentary, short stem Dark grey
Alternate action Cream
Momentary, higher weight? Black Tall
Momentary, higher weight Cream SKCCAF
Momentary, Facit mount Cream

SKCCAC is another model number, but the switch it belongs to is not identified.

Switch models are in turn divided into specific parts with a suffix added to the model number. A small number of these are known:

Part Batch date Customer Characteristics Reference
SKCCAF002A 1987-06-09 AUI.G.G Single obround sealant slot, grey switchplate, tinned terminals Deskthority/Flickr
SKCCBJ0001 Divided obround sealant slot, short white switchplate, tinned terminals Deskthority
SKCCBK0001 Divided obround sealant slot, tinned terminals; internals have not been observed Deskthority


The scope of KCC Series is unclear. Part SCK41505 would fall under “SCK” but it’s not known what became KCA and what was classified under KCC. One Ambit catalogue depicts non-standard model KCC10002 as having a narrow plunger with an external return spring, which does not match any known type, including “SCK” (which has a wide, flat sheet metal plunger and large diameter spring). The same catalogue depicts KCC10902 as the same design less the spring but calls it “as KCC10902 type but self locking”, which is impossible as the alternate action types have “3” in the switch type position, so something like KCC10302 would be expected.

There is also KCA to contend with, absent from catalogues and advertisements but known to exist.


The design has changed a number of times over the lifetime of the series. These switches have been found with tall black, tall grey and short white “switchplate” contact assemblies as expected.

Notably, the exterior characteristics changed several times:

The base of the switch first gained chamfered side edges. This is assumed to be the first change as most examples have these chamfered edges.

By 1987, the recess that holds the terminal sealant changed from straight sides to curved sides. This can be seen in the large batch of 88,000+ SKCCAF002A switches acquired by Standard Supply, of which one 4000-piece box previously found its way to Quest Components. (See SKCC Tall Cream on the Deskthority wiki for photos.) As expected, these switches have grey “switchplates”, with an additional retaining ridge to hold the switchplate.

There are (or at least were) also surplus SKCCBJ switches in China. These have short white switchplates, which would date them to around 1989 or later. These have the bottom recess divided into two halves. The rounded ends of the recess are retained. The ridge that holds the switchplate is retained in the mould, even though it appears to serve no purpose at this stage.

Black switches

A topic of continued confusion, some tall switches are found with black plungers. Generally no more than a few are found in the same keyboard, suggesting that they are specified identically to the cream equivalents.

At least two instances have been encountered with entirely tall black switches:

Since tall cream is model SKCCAF, there is plenty of capacity for earlier models in the SKCCA subseries, and for black to be an older version. Alps are already known to have changed all the model numbers and plunger colours within SKCL/SKCM series around 1989, and this could have been the case here, too.

Double action

A double-action switch exists that is associated with KCC. This was first seen in keyboards KCCAA087 and (possibly) KCCAA147, both from Canon typewriters, and both for sale at Electronics Plus in 2018. These switches were then rediscovered in Canon AP350X typewriters, and verified as double-action, something Electronics Plus firmly denied despite clear evidence to the contrary.

The exact series they belong to is not known. They resemble KFF more than anything else, but KFF does not use that contact assembly. The design is similar to Alps SKCLKB double action, but as these are found in KCC/KFCC keyboards, they are more likely to be classed as KCC, despite having a very different plunger design.

Alps utility model S58150232U covers a variation on this switch, where the stage two leaf spring is not present.

KCC Series was advertised to contain a double action type, so is is fairly likely that this type is indeed KCC Series.


KCC switches are commonly encountered in vintage equipment, and thus they are commonly encountered with broken plungers. “Savel” has produced a 3D model of the standard KCC plunger in STL format suitable for printing replacement plungers.


SCK is a related series that uses the same shell. The circular raised area on the top of the switch, that serves no purpose in KCC, is used in SCK to hold the external return spring. SCK has a stamped metal plunger. The internal have never been seen. This series is only known from Roland equipment.


There is tentative evidence to suggest that KCC series was previously known as SCH series. See under series names and model numbers for more information.


Apple II service literature shows that the Apple II “switchable” keyboards used “KBB” switches from Alps. The illustration of the keyboard is degraded through photocopying, and no Alps part numbers are given. There has yet to be any evidence to show unusual Alps switches, so the meaning of “KBB” remains a mystery. Allegedly there are a number of other switch types used in Apple II computers, according to a German site, but none of these types are illustrated with photos and none of them appear to be common types. The switches in the service documentation are KCC-shaped, but the existence of SCK shows that at least two series shared that shell (and three if you count General Instrument Series S950).


KCA is known only from the Roland CR-78 service manual. There is a possibility that KCA shares the same external design as KCC.

Clare-Pendar S950

Clare-Pendar Series S950 is a virtually identical switch series to KCC. Examination of the mould markings indicates that either Alps moulded the parts (perhaps for assembly in one of the Mexico factories), or that Alps licensed the plans for the tooling system to General Instrument. Series S950 differs from KCC series in using Clare-Pendar mount, and in offering an angled keystem option.