HP 15254A Keyboard

HaaTa · 28 Nov 2015, 06:37

Ok. It seems every year I find at least one keyboard, that introduces me to something new. Completely new.
Like most old HP gear, HP doesn't generally disappoint, though for the most part, it's just quality. Not a lot of interesting ideas.

However, this keypad (it tries to call itself a Keyboard, but it's trying just a bit too hard

) really takes the cake this year.

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Apparently, this keypad came from the estate of an old HP engineer, but other than that, not much is known about it.

Ok, srsrly. WTF is up with that giant cylinder thing.

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Solenoid? Would be the largest solenoid I've ever seen in a keyboard (typewriters don't count

).
Motor? Haptics in a 1970s keypad, wtf?
Anyways, it's seriously heavy, lots of copper in there.

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Normally, I'd go onto the switches, because they are pretty neat. But really, I needed to figure out what that cylinder was for. Video time.

Ok, mystery 1 is solved, giant cylinder thing is big-ass solenoid. But, why is it moving the plate...?

Hah! I guess this brings new meaning to the term "locking" switches. Solenoid locking switches!

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Neat! HP Mouse Trap switches (not quite the same as the Cherry ones, likely newer).

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Oh, and the switches. With a bit of lube could be quite nice. Clicky, though not very tactile. The sliders/keycaps (and the locking plate) tend to stick a bit.

Flickr Album

REVENGE · 29 Nov 2015, 06:25

Comon now, give me some speculation as to why there needs to be a lockout function in the first place!

HaaTa · 29 Nov 2015, 07:49

You mean besides preventing someone from accidentally launching some nuke at a soviet country?

Chyros · 29 Nov 2015, 12:04

How in God's name do those mouse traps even work?! xD

Scottex · 29 Nov 2015, 14:02

Chyros wrote: How in God's name do those mouse traps even work?! xD

Something like this maybe?

The red area being the contact pads

Engicoder · 29 Nov 2015, 14:46

Any idea what the use case for this was? Its obviously to lock out input, but why the physically lockout instead of just handling it electronically by not detecting/sending keystrokes?

HaaTa · 30 Nov 2015, 01:42

This is the 70s, electronically locking out was probably a lot more expensive than you think it'd be. Doing things mechanically up until the 80s was often the cheaper/simpler way.

This is an earlier mousetrap switch, which I think may be Cherry's first keyboard switch (1959'ish):

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You can see the gold cross-point that Cherry touts so much.