Specifications

M’ILSTD-1472E
5.4.3.1.3 Keyboards.
5.4,3 .1.3.1
~. Arrangementsof ush buttons in the formof keyboardsshouldbe used when
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alphabetic,numeric,or specialfunctionin ormationis to be enteredinto a system.
5.4.3 .1.3.2 Layout and confirmation, The key configuration and the number of keys arc
dependent upon the predominant type of
informationto be entered into the system. The major forms
that keyboards can take, which aid in the entry of such information, am given below:
a. Numeric keyboard. The configuration of a keyboard used to enter solely numeric information
should bea3x3+ lrnatrix withthezero digit centered onthebottommw.
b. Abhanumeric keyboard. Keyboard conf@ations for entry of alphabetic and some numeric
information shall mnforrn to MIIATD- 1280. Where entered data varies from primarily
alphabetic to primarily numeric, two sIternatives are
femd: Ruvide a keyboard of the type
rshown in Figure 2 of MIIATD- 1280 (no sepamtion tween alphabetic and numeric
chametem), or provide a qamtion
to emphsize thetwo sqarate hnctions, with the numeric
keyboaldlocated tot.heright of thestanddkeyboard.
5.4.3 .1.3.3 Dimensions, resistance. dis~lacement, and sernration. Dimensions, resistance,
displacement and separation between
adjacent edgesof the pushbuttonswhichformkeyboardsshall
conform to the criteria in Table X. For a given keyboard these criteria shall be uniform for all
individual keys. For applications requiring operation while wearing (tigger finger) arctic mittens, key
size shall be not less than 19 mm (0.75 in). Other parameters are unchanged from those of bare-
handed operation (see Tabie X).
5.4.3 .1.3.4 S1OIM.The slope of nonportable keyboads should be 15-25° ii-m the horizontal.
The prefemed slope is 17-18°. ‘I%cslope of a portable device should be capable of being varied
according to the pmfemnce of the operator.
5.4.3 .1.3.5 Mukh)kke
-. -~
. .
gmorethanone keybonrdshal lmaintainthe
same Configuration
for dpbummic,
numeric, and aped function keys throughout the system.
5.4.3 .1.3.6 Feedback Where applicable, feedback shall be provided to inform the operator that
the intended key was pmssd and that the next operation maybe initiated.
5.4.3.1.4 Toggle switch control$.
5.4.3 .1.4.1
Use. Toggleswitches shotxid be used where two discrete control positions am
requiredor wheres- limitations are severe. Toggleswitcheswith tiuee positionsshall be used only
wh&ethelf9e ofnruteryooHV1Or kgend 8wi@h00ntrQiisnui&si’ble orwiKmthe&@e switchis
spring-loaded to a center-off position. Three positiontoggle switches, spring-loaded to center-off
from only one other positiq shall not be used if release fkom the spring-loaded position results in
switch handle travel beyond the off position. (Toggle switches arc discrete position controls. For
small controls that am the same size and shape as toggle switches, but used for making continuous
adjuslmeab,
stx2Aeuers.)
5 4.3. ],4.2 Acciden@]actuation. When preventing accidental actuation is important (i.e.,
crmcai or hnrdous amehons
wcdd remit), chunnd gtuiidu, MWO-tA4wk swidwh, w db
cqllivatent prrvrntirm rntchtmisrm shall be provided. Safetv or lock wire shall not he used.
Resistance of lift-to-unlock mechanisms shall not exceed 1~ N (3 lb). An open cover guard shaIl not
illl{’rf{’r~’\\’itlltlw(Iprr:llimlnf lhcpntrctd drl.iccor xllnccntcnntrok
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