Editing Datanetics DC-60 series

{{TODO photo|more=true|reason=need cream, latching, brown etc}}

{{infobox dswitch
| image name          = Datanetics DC-60 -- infobox.jpg
| manufacturer        = [[Datanetics]]
| product code        = 
| family              = DC-60
| switch type         = [[Tactile]]
| contact mechanism   = [[Contact mechanism#Metal leaf|Metal leaf]]
| switch mount        = [[Switch mount#Plate mount|Plate mount]]
| introduced          = 1973
| lifetime            = 15M
}}

'''Datanetics DC-60 series''' is the lower-profile, lower-cost alternative to [[Datanetics DC-50 series]]. DC-60 switches are fairly uncommon, and are best known for being used in Fluke Y1700 keyboards. In addition, they have also been used on Fluke test equipment from the era such as the high end Fluke 5440B DC calibrator. All known examples are unbranded. Unlike DC-50, this series is not known to be patented.

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Needs more investigation, since it seems not to be assembled the way I thought it was.

==Design==
[[File:Datanetics DC-60 -- shell sealing.svg|500px|centre]]

The shell appears to be heat-sealed via two posts in the upper shell that are bonded into holes in the base.
-->

==Construction==
The two switch contacts are made from inlaid 302 stainless steel strip, sourced from Technical Materials, Inc. (now Materion Corporation).

One of the contacts is stepped, such that as the separator bar in the slider reaches the step, the contacts close suddenly and the slider is pushed downwards. This downward push from the contacts provides the tactility.

==Variants==
The slider colour was not specified, but it appears to be an indicator of the switch profile, with evidence suggesting low profile is brown and grey, lower profile is black, and lowest profile being white, with cream appearing to be a compromise between lower and lowest profiles not shown in the extant brochures. This remains pure speculation owing to no measurements yet existing for any encountered variants.

*Brown slider, low profile<ref name="DT_brown_cream" />
*Grey slider, low profile (below)
*Black slider, lower profile (below)
*White slider, lowest profile (below)
*Black slider, latching (appears to be lower profile)<ref name="DT_black_latching" />
*Cream slider<ref name="DT_brown_cream" /> — this might be a fraction of a millimetre lower in profile than "low" profile, but moreover, this variant has a much narrower cross which appears to be Cherry MX mount<ref name="AliExpress-cream" />

In 1975, only the standard (AKA lower) and low (AKA lowest) profiles existed. By 1981, a marginally taller ("low") profile had been introduced, along with a latching variant.

Officially, all switches are tactile, but the lowest-profile (snap-on) switch provided by Meryl Miller is inexplicably linear. His medium profile tactile switch is highly tactile, and late-issue ITT-made lowest-profile switches have been obtained with only weak tactility. It is not known if linear switches went into production; Sandy reports the Fluke Y1700's switches as linear with dust-impaired feel, which does not guarantee that his medium-profile switches do not share the same weak tactility as the contemporary lowest-profile switches.<ref name="Y1700" />

===Known part numbers===
{| class="wikitable row-headings"
! Part no. !! Action    !! Profile !! Guide posts !! Defined in
|-
| DC-61-01 || Momentary || Lowest  || Present     || Datanetics 1975, ITT Datanetics 1981
|-
| DC-61-02 || Momentary || Lowest  || Absent      || Datanetics 1975, ITT Datanetics 1981
|-
| DC-61-03 || Momentary || Lower   || Present     || Datanetics 1975, ITT Datanetics 1981
|-
| DC-61-04 || Momentary || Lower   || Absent      || Datanetics 1975, ITT Datanetics 1981
|-
| DC-61-05 || Momentary || Low     || Present     || ITT Datanetics 1981
|-
| DC-61-06 || Momentary || Low     || Absent      || ITT Datanetics 1981
|-
| DC-62-03 || Latching  || Lower   || Present     || ITT Datanetics 1981
|-
| DC-62-04 || Latching  || Lower   || Absent      || ITT Datanetics 1981
|-
| DC-62-05 || Latching  || Low     || Present     || ITT Datanetics 1981
|-
| DC-62-06 || Latching  || Low     || Absent      || ITT Datanetics 1981
|}

===Evolution===
[[File:Datanetics DC-60 evolution.svg|centre]]

The design changed with time. The heat-stakable guide posts (fixing pins) appear to have been shortened significantly at some stage, from 2.92 mm in 1975, to 1.02 mm in 1981. The 1981 brochure still depicts long guide posts and still describes them as heat-stakable, but the specifications, which match the form most commonly found, is for posts that may only be long enough to serve as fixing pins. The diagonal corners were also removed at some point, being absent from both Sandy's Fluke Y1700 examples, and from terrycherry's cream examples.

==Keyboards==
*HP 9825A — brown gen. 2, 1979<ref name="HP9825A" />
*Fluke 1720A Programmer Keyboard — black gen. 2, 1980<ref name="1720A" />
*Fluke Y1700 Keyboard — black gen. 3, 1990<ref name="Y1700-2" />
*Fluke 5440B DC Calibrator<ref name="5440B" />

==Gallery==
===Overview===
<gallery widths=250 heights=187>
Datanetics DC-60 assorted 1.jpg              | Three different DC-60 switches, showing three switch profiles
Datanetics DC-60 assorted 2.jpg              | Assorted switches, disassembled
Datanetics DC-60 assorted 3.jpg              | Assorted switches, disassembled
Datanetics DC-60 assorted 4.jpg              | Switch detail
Datanetics DC-60 assorted 5.jpg              | Slider detail
File:Datanetics DC-60 -- unsealed base.jpg   | Unsealed switch base, showing securing pins in their initial state
</gallery>

===Black lower profile===
<gallery widths=250 heights=187>
File:USw LXBB03 -- switches.jpg              | Switches
File:USw LXBB03 -- keycap mount.jpg          | Keycap mount (Fluke Y1700 keycap)
File:USw LXBB03 -- bottom.jpg                | Bottom
File:USw LXBB03 -- opened.jpg                | Opened
File:USw LXBB03 -- slider.jpg                | Slider
File:USw LXBB03 -- contact separator bar.jpg | Contact separator bar in the slider
File:USw LXBB03 -- contacts.jpg              | Contacts
File:USw LXBB03 -- contacts, detail.jpg      | Contacts, detail
</gallery>

<gallery>
Datanetics DC-60_opened switch.jpg|Opened switch
Datanetics DC-60_parts1.jpg|Switch parts
Datanetics DC-60_parts2.jpg|Switch parts
</gallery>

==Specifications==
*[[:File:Datanetics DC-60.pdf|Datanetics DC-60 brochure]] (1975)
*[[:File:ITT Datanetics DC-50 and DC-60 Key Switches.pdf|ITT Datanetics DC-50/DC-60 Key Switches brochure]] (1981)

==Other materials==
*[[:File:TMI -- clad strip advert ft Datanetics DC-60.jpg|Technical Materials, Inc. magazine advertisement from 1980]]

==References==
<references>
<ref name="DT_brown_cream">Deskthority — [http://deskthority.net/keyboards-f2/usw-lxbb03-t9416.html USw LXBB03?]</ref>
<ref name="DT_black_latching">Deskthority — [https://deskthority.net/keyboards-f2/id-this-keyswitch-t12808.html ID this keyswitch]</ref>
<ref name="HP9825A">Deskthority — [http://deskthority.net/keyboards-f2/hp-9825-keyboard-restoration-t7951.html HP 9825 keyboard restoration] Posted 2014-05-05. Retrieved 2015-08-03.</ref>
<ref name="Y1700-2">Flickr — [https://www.flickr.com/photos/triplehaata/sets/72157661691582309/ Fluke Y1700 Keyboard]</ref>
<ref name="1720A">Deskthority — [https://deskthority.net/keyboards-f2/fluke-1720a-programmer-keyboard-switches-t13242.html Fluke 1720A Programmer Keyboard - Switches?]</ref>
<ref name="AliExpress-cream">AliExpress — [http://www.aliexpress.com/store/product/5pcs-lot-infrequent-Keyboard-switch-yellow-shaft/1113036_32543736834.html 5pcs/lot infrequent Keyboard switch yellow shaft …]</ref>
<ref name="Y1700">Sandy55 — [http://sandy55.fc2web.com/keyboard/y1700.html FLUKE Y1700]</ref>
<ref name="5440B">EEVBlog - [http://www.eevblog.com/forum/repair/repairing-a-5440baf-dc-calibrator/msg984978/#msg984978 Repairing a 5440B/AF DC Calibrator]</ref>
</references>

[[Category:Datanetics switches]]
[[Category:Metal contact switches]]
[[Category:Tactile switches]]
[[Category:Alternate action switches]]
[[Category:List of all keyboard switches]]