Symbolics keyboard PN 365407

By Xah Lee. Date: . Last updated: .

This is used in Symbolics 36xx series lisp machines , around 1985.

[see Lisp Machine Keyboards]

There are 3 revisions, A, B, C. Rev C had LEDs in the Caps Lock and Mode Lock keys.

symbolics keyboard pn 365407 rev c dc50f
Symbolics keyboard pn 365407 rev c. ~1985

here's a big photo 4000×3000

Rev A

symbolics keyboard pn 365407 rev A 26717
Symbolics keyboard pn 365407 rev A [image source, by webwit]
symbolics keyboard 365407 rev A vs 364000
Symbolics keyboard, 365407 rev A (top) and the previous model pn 364000 (bottom). The new one is more compact. [image source, by webwit]

[see Symbolics Keyboard PN 364000]

Rev C

symbolics keyboard pn 365407 rev c 87315
Symbolics keyboard pn 365407 rev c
symbolics keyboard pn 365407 rev c 0ab77
Symbolics keyboard pn 365407 rev c

Rub Out key

2017-05-18 ScottBurson wrote

On an ASR33 Teletype, backspace simply moved the carriage one character position to the left.

Rubout was a different concept entirely. The ASR33 had a paper tape punch and reader. The Rubout character was 0x7F, i.e., it had all bits set. So, to “rub out” an erroneous character from the paper tape, you could back the tape up in the punch to the desired character (by pressing a button on the punch; there was no character that invoked this function) and hit Rubout; this would punch the tape at all seven holes, changing whatever character had been there to a Rubout. (The software ignored Rubout characters on input.)

When the world moved on from Teletypes, it was natural for people to want a single keystroke that meant “delete the previous input character”. But there was evidently some divergence of opinion in the industry as to whether that should be Backspace or Rubout — notwithstanding that the ASR33's concept of Rubout didn't really map at all onto the new hardware.

[2017-05-19 from]

2017-05-18 kps wrote:

notwithstanding that the ASR33's concept of Rubout didn't
really map at all onto the new hardware.

If you are working with paper tape, Rubout (DEL in ASCII parlance), like every other code, advances the tape when punched. So, if the tape is a stream of characters, DEL erases the one under the cursor and leaves the cursor on the character formerly to the right. That is, Rubout/DEL is defined as a ‘forward delete’ operation, and that's something that remains useful. That leaves Backspace as the natural choice for entering ‘backward delete’ on a keyboard, at least after 1979 when you have the ANSI X3.64 escape sequences for explicitly nondestructive cursor keys. I think there's a reasonable argument for Backspace being nondestructive for overstrike effects (accents, underlining, APL, etc.), especially when received by a terminal, but I know none for changing the meaning of DEL.

Note the dedicated parenthesis keys.

Key Switch

It appears, there are different models of 365407, using different switches.

symbolics keyboard pn 365407 rev A f950b
Symbolics keyboard pn 365407 rev A [image source, by webwit]

Hi-Tek Series 725 was Hi-Tek Corporation's DIN-compliant keyboard series, introduced in 1983; the name refers to how these keyboards are a maximum of 0.725″ from the desk surface.[1] "Series 725" also refers to the switches used in these keyboards.

2018-09-26 from

Symbolics pn 365407  ITW switch cfc7c
Symbolics 365407 with ITW magnetic valve switches [image source] see

ITW magnetic valve is a provisional name which refers to a type of electromagnetic switch patented by ITW and manufactured by ITW and Devlin.

2018-09-26 from

Previous Model

The previous models is PN 364000, and is compatible to it.

symbolics keyboard pn364000 mrq3w-s349x179
Symbolics Keyboard PN 364000

Lisp Machine

  1. Lisp Machine Keyboards
  2. SAIL Keyboard
  3. Knight Keyboard
  4. Lisp Machine LMI-CADR keyboard
  5. Space-Cadet Keyboard
  6. Symbolics Keyboard PN 364000
  7. Symbolics keyboard PN 365407
  8. Racal-Norsk KPS-10 Lisp Prototype Keyboard
  9. History of Emacs and vi Keys

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