Alps SKBL/SKBM series
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This article requires additional photographic illustration — missing variants |
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| Manufacturer | Forward Electronics |
|---|---|
| Introduced | 1991 |
| Discontinued | 2012 |
| Switch type | Tactile; clicky; linear |
| Sense method | Metal leaf |
| Rated lifetime | 10M |
| Bounce time | 5 ms |
| Total travel | 3.5 mm |
| Keycap mount | Alps mount |
| Switch mount | Plate mount |
Alps SKBL/SKBM series (latterly Forward SKBL/SKBM series following rebranding), commonly known as simplified Alps due to its reduced part count over Alps SKCL/SKCM series, is a series of switches which appear to have been manufactured since its inception by Forward Electronics in Taiwan.
Contents
Nomenclature
Forward's SKBL and SKBM series are commonly known as "Fuhua" and "Fukka" switches. "Fuhua" comes from the mistaken use of the company's Chinese name (福華電子股份有限公司 – Fuhua Electronic Co. Ltd.) instead of their English language name of Forward Electronics. This in turn got corrupted to "Fukka", a term that has seen consistent use to this day.
SKBL and SKBM are the official series names as once found on the Forward Electronics website.
History
According to Forward Electronics, SKBL/SKBM series was introduced in 1991.[1] However, the earliest discovered examples of keyboards using these switches are from 1995, in particular the Forward Electronics FDA-102D. Forward Electronics specifications SKBL-E01 and SKBM-E01 both appear to be from 1995, which fits in with the earliest sightings of the switches.
Alps Electric ended their 30-year joint venture with Forward Electronics in March 2000;[2] from this point onwards, until the product series was discontinued in early 2012, there was no relationship with Alps.
Around the time that the Matias Tactile Pro 2.0 was introduced, the "ALPS" branding disappeared from the switches; Edgar Matias has reported that Forward Electronics lost their licence to use the Alps branding, requiring switch retooling.[Citation needed] What is known is that the switches were rebranded: the new-style Alps logo was removed from the top, and the old oval logo on the bottom was replaced by the letters "F D". The design drawings were amended to match.
Matias Corporation was responsible for continued production of SKBL/SKBM switches, by taking a gamble on the million-switch order required to keep the factory alive; this was required to maintain production of the switches used in the original Tactile Pro.[Citation needed] However, production was finally terminated in early 2012. The final batches of the Tactile Pro 3 had to use their new Matias switch, as stocks of SKBM switches ran out prematurely. The Matias switch is a clone of the SKBL/SKBM series.
Details
SKBL/SKBM series switches have significantly less mould numbering compared to SKCL/SKCM. The encircled characters are not present; the only characters appear to be mould cavity identification. The numbering consists of a single alphanumeric character in each of the north-west and north-east positions. This numbering pattern appears to be unique amongst Alps switches and clones, and is a useful guide when examining a switch with no branding, which could be early complicated or late simplified.
Recognition
Simplified Alps switches share the same exterior design as complicated Alps, but the logo and mould numbering differ, making recognition fairly straightforward. Although there are several differences between simplified Alps switches and archetypal complicated Alps switches, there are also numerous variations of complicated white Alps, and the redesigned mould numbering is the only difference that appears to be specific to simplified Alps.
Archetypal complicated Alps switch; later switches lost the slits, and older switches lacked the Alps logo on the top
Simplified Alps, with simple numbering, heavily raised bold Alps logo, and the contacts at the front, causing it to appear "upside down"
Later simplified Alps switches with the logo removed; these appear to all have the writing orientation corrected
Criticism
It has a reputation for being loud.
The springs in the keyboard could reverberate and cause noise when any key is pressed to the bottom hard enough. That sound has been called "ping" or "the chorus of springs".
Variants
Official
The official list of models is as follows, taken from the Forward Electronics website in 2004 and 2008, with the colours taken from the design drawings:
| Model | Type | Operating force | Official colour |
|---|---|---|---|
| SKBLFE | Linear | 60 gf | Yellow |
| SKBLFF | Linear | 90 gf | |
| SKBMFA | Clicky | 70 gf | White |
| SKBMFB | Tactile | 70 gf |
Lifetime is given as 10 million cycles, and bounce time as 5 ms maximum. The switches are rated for DC 12 V 100 mA maximum. Contact resistance is 1 Ω maximum initially, and 5 Ω maximum at end of life.
The schematic for SKBLFE shows no position for an LED, and Forward SKBL Black indeed has no LED slot. However, a small monochrome photograph on the Forward Electronics website in 2004 showed a linear switch with integrated LED. No mention is ever made of this discrepancy, and no LED switch has been sighted; Matias keyboards used Xiang Min KSB-N switches for the illuminated keys instead.
Discovered
Actual discovered switches do not appear to correspond fully with the published specifications. In particular, the use of colour seems to be arbitrary, with clicky switches being found in white, black and grey, and black switches in clicky, tactile and linear forms. Inspection of "F D"–branded white and grey switches shows no difference of any kind except for the slider colour. The existence of both colour sliders in both Alps and Forward branding remains a mystery.
"Alps" below refers to Alps-branded switches, and "Forward" to Forward-branded switches.
| Switch | Key feel | Force | Years | Notes | |
|---|---|---|---|---|---|
|
|
Alps SKBM White Forward SKBM White |
Clicky | Typical weight is 65 gf[Citation needed] | …—2012 | |
|
Alps SKBM Grey Forward SKBM Grey |
Clicky | Measured at 60–65 gf[Citation needed] | ||
|
Alps SKBM Black | Tactile | |||
|
Alps SKBM Black Click | Clicky | |||
|
|
Forward SKBL Black | Linear |
Gallery
White SKBM switches alongside a green Xiang Min KSB-LE switch in the Tactile Pro 3
Switch internals
Close-up of the simplified contact mechanism
Upper shell as seen from below
Branding and mould numbering detail
Comparison with Alps SKCL Green, top
Comparison with Alps SKCL Green, bottom, showing replacement "F D" branding
Specifications
- Forward Electronics specification SKBL-E01 (1995) with revised SKBLFE000A drawing showing FD logo
- Forward Electronics specification SKBM-E01 (1995) with revised SKBMFA000A drawing showing FD logo
- SKBLFE drawing (1999; linear with yellow slider and no LED recess)
- SKBMFA drawing (2002; clicky with white slider)
External links
- Forward Electronics — KEY SWITCH (Wayback Machine, 2004-02-25)
- Forward Electronics — SKBL (Wayback Machine, 2008-06-25)
