Background and Identification
Introduced on March 2, 1987, the original Apple Extended Keyboard (AEK Model M0115) is a keyboard first sold separately alongside the Macintosh II and SE. Then in 1990, the Apple Extended Keyboard was replaced by the Apple Extended Keyboard II (AEKII Model M3501) which came prepackaged with Apple Professional Desktops beginning with the Macintosh IIsi.
Both versions of the Apple Extended Keyboard are very similar and the main difference between them is the addition of adjustable height legs in the AEKII and other minor changes. The two keyboards both used Apple Desktop Bus (ADB) to connect to the host computer with ports on either side, allowing for daisy chaining of another input device, most commonly a computer mouse or trackball. A daisy chain is the connection of several devices in a linear chain.
As the use of USB connections increased, beginning with the original iMac, it led to new keyboard designs. These new keyboards used rubber dome switches instead of the Alps Electric switches. Accordingly, this switch created a market for third-party keyboards that replicate some of the AEK aesthetic and feel. Matias’ line of Tactile Pro and Quiet Pro keyboards are the most notable for this type.
Unique features of the Apple Extended Keyboard include (Wikipedia):
- A separate power key using a different key cap.
- Caps Lock Key that physically locks down when activated, considered to be better for touch typists.
- Alps Electric Co. brand mechanical key switches, credited for their good sound and feel.
- Large spacing between keys, especially the top function keys and others.
- The width of the keyboard matches the width of the Macintosh II.
- The height allows it to fit under the "chin" of the Macintosh SE.
- Two small cylinders project vertically from the top of the keyboard on either side of the function keys. These were used to hold templates with application-specific key guides.