Cherry M8

From Deskthority wiki
Jump to: navigation, search
Template icon--Illustration.png This article requires photographic illustration — clear, cropped photos illustrating a selection of the Hirose Cherry and (German) Cherry variants (from above and below)
Cherry M8
Cherry M8.jpg
Manufacturer Cherry, Hirose
Product code M8xx-xxxx
Discontinued 2013
Switch type Linear, tactile
Sense method Metal leaf
Rated lifetime 10M
Bounce time 2 ms
Total travel 2.5 mm
Switch mount PCB mount

Cherry M8 refers to several switch families that predated Cherry MX switches. They are rare, low profile switches that were made in a multitude of variants. Cherry issued a final-buy notification for the M8 series in October 2013; it is now discontinued.


Mechanism

Cherry M8 switches use a gold-silver contact mechanism. When at rest, the slider separates the two contacts, with one bent outward against the slider, under tension. As the slider enters the housing, the contact under tension approaches the second contact, following the grooves on the upper portion of the slider. When pressure has been removed from the switch, the spring pushes upwards, overcoming the force provided by the contact and returning the slider to its start position.

The contact mechanism is the same as that of the Cherry M9 switch.

Variants

In part numbers, the first character after M8 indicates the switch's rating, including the contact plating material and its permissible loads. The switches are sometimes divided into sub-series based on rating:

Characteristic M81 M82 M84
Voltage min/max 28 V AC/DC 60 V AC/DC 12 V AC/DC max
Current min/max 100 mA max 100 mA max 10 mA max
Contacts material AuAg26Ni3 AgPd30 AuAg10

Other variations include:

LED
Optional fitment of an integrated LED
DPST
Double-pole, single-throw operation
Tactile operation
The switches could be ordered with linear, tactile or German Postal Service tactile specification force curves
Cover
Covered and uncovered versions were available; covered switches are significantly rarer than the uncovered versions
Keycap mount
Multiple keycap mounts were available

Typically, switches in European keyboards are SPST but have a DPST slider, and have space for an integrated LED. Japanese keyboards have all been sighted with a variant design, using an SPST-only slider and no LED space. This variant design has also been used in a German keyboard.[1]

Covered switches are largely identical to uncovered switches. The cover adds to the height, and requires a taller keystem on the slider. The cover from a covered switch fits on an uncovered switch, but the keystem does not protrude through its hole.

Cherry M85

The Cherry Keymodule M8 brochure includes a section on the M85 sub-series. M85 switches have a hollow slider designed to support a central LED. The shell is visibly different from other M8 switches, but the internals are assumed to be largely the same. M85 switches are not intended for use in computer or typewriter keyboards.

Hirose Cherry M8

Hirose in Japan manufactured a variant of this switch, branded HIROSE CHERRY on the base.[Citation needed] All Hirose Cherry M8 switches found to date have been of the SPST-only, uncovered (open) type.

It is not clear whether the Hirose Cherry M8 is Hirose Cherry mount.

Recognition

Keyboards

Cherry

  • Some Atari 800 keyboards (cream I-beam slider uncovered, and a covered version with bar mount slider)[2]
  • Basis 108 keyboard (uncovered; standard white, and black SPST-only)
  • Bondwell 8T portable (semi-Cherry MX-compatible sliders; uncovered; used for the numeric keypad)[3]
  • Cherry G80-0662 (uncovered)
  • Genest Technologies Numerikeys (uncovered)[4]

Hirose Cherry

  • Epson PX-8 keyboard (white and black stems)
  • Epson HC-20 (white stems)[5]

Gallery

M84A-0100

The depicted switches are from Cherry's last ever batch of M8 switches, made in late 2013 or early 2014.

Covered

The switches depicted are NOS from AliExpress, of unknown part number.

References

  1. Deskthority — Basis 108 - Cherry M8 low profile
  2. AtariAge Forums — 600/800XL Keyboard variants
  3. Geekhack — SKCL (complicated linear) with cream colored sliders? Posted 2014-02-02. Retrieved 2015-07-23.
  4. ちゃたりたいね — GENEST TECHNOLOGIES NUMERIKEYS EFX6BBNUMKEY JAPAN Dated 2014-08-25. Retrieved 2015-07-23.
  5. MouseFan — EPSON HC-20 '83 JAPAN Retrieved 2015-07-23.