Keyboard models

Note KSN means Keyboard Serial Number

Remember that Keyboards are one of the easiest items to switch from one machine to another. Do not be too dogmatic about the serial numbers attached to a particular machine.

Note about Serial Numbers near #4000 - #5000: I have found that a white thread locker was applied. If you have one of these machines only use an Anex 3980 +1 X 75 Phillips Screwdriver. If any screw appears to "Cam Out" stop immediately and hammer the Anex into the screw head before trying to remove the screw further. Other wise you will likely need to use a 1/8 inch Left Hand drill bit to remove the screw head. Carefully remove top of case. From the inside of the case us a ENGINEER PZ-58 Screw Removal Pliers to back the screw out as far as it will go then use the PZ-58 from the outside to remove the screw.

Non destructive exam of Keyboard

I have tried to look for a reliable way of knowing which mechanical keyboard is with each CPM Kaypro machine. After reviewing my collection I can only find 3 manufactures of CPM Kaypro keyboards. SMK, Keytronics and Maxi-switch. All three manufacturers mostly kept the same design throughout the entirety of the CPM machines. To non-invasively determine which mechanism you have, unlatch the keyboard off of the machine’s body. Place the keyboard in front of you like you would type on it. Tilt the keyboard so the “Kaypro” label comes towards you. Look in the space between the front of the spacebar and the metal keyboard cover.

If you see two metal bars coming from the front of the space bar the keyboard is an SMK mechanism.

If you see the tan PCB sticking out of the front beyond the black metal support grid it is a Maxi-switch.

If you can’t see either of these then it is a Keytronics mechanism. The Keytronics is the only mechanism with the foam and foil system which would likely need to be rebuilt if it is original.

SMK

SMK Keyboard Models C, D, E, and Z (Tactile)
	Found in Type A Found in #2775 - KSN 028401404#8409 - KSN 10820673, #12275 - 11821370, #12654 - 12822711, #13480 (Irregular) - KSN 058306857, #15453 - KSN 12823872, #16679 - KSN 12825061, #43168 - KSN 12824823 (Kaycomp Keyboard) Type B #16288 - KSN 01838471,#17083 - KSN 12827743, #23201 - KSN 01839675, #27336 - KSN 03837134 #42891 - KSN 048304571 (Label 4499 09/13/83), #43486 - KSN 078401557, #45618 - KSN 03839356 (Label 1637 03/21/83), #57145 - KSN 02832653 (Case stamped (Mar 2? 19?? likely 1983), #98465 - KSN 098305790 (Label 2147 04/29/83), #127311 - KSN 038410909, #129891 - KSN038407222, #148830 - KSN 078325471, #273643 - KSN 128303533, #288536 - KSN 068406464, #405393 - KSN 068400434, #423193 - KSN 088302693

Keytronic

Keytronics Keyboard A65-02207-2O1D (Capacitive)	Found in #3590 - KSN 05420, #4207 - KSN 50845 (8/82), #4222 - 50996 (8/82), #4223 - KSN 55080 (8/82), #7954 - KSN 44011 (10/82), #20250 - KSN 06229 (1/83), #21460 - KSN 06317 (1/83), #36960 - KSN 09635 (9/82), #209236 - KSN 34770 (6/83)

Keytronic Keyboard Rebuild

tex ELEC Foam and Foil pad kit

Adrian Black's TRS Foam and Foil Replacement

Maxi Switch

Maxi-Switch Keyboard 2160150 (Tactile)	Found in #73356 - KSN 11323 06/09/1983, #76797 - KSN 017270 07/30/1983, #99393 - KSN 5777 07/30/1983, #102622 - KSN , #204928 - KSN 030248 12/22/83, #240019 - KSN 026620 12/12/83, #275940 - KSN 027827 11/02/84

Type A vs Type B Keyboard

On early machines (around #8,000) There exists two types of Keyboards. In an early article they are defined as Type A and B. It turns out that this is a key indicator of who manufactured the keyboard and if it is a tactile switch or foam and foil keyboard. SMK appears to have only made the type A keyboards with tactile switches in the early days. Keytronics made the Type B keyboards with a foam and foil keyboard that degrades over time.

From the November 1983 Issue of Radio Electronics

	Type A	Type B
External View	SMK	Keytronics
Internal Key View	SMK	Keytronic Early SMK Later SMK
Board Appearance	SMK	Keytronic SMK
Parts		Type B is a single piece