Editing Pertec XL40 keyboard (section)

==Description==
This is the keyboard for the Pertec XL40 microcomputer introduced in 1977. The XL-40 was also marketed by Triumph-Adler in Europe as TA1540 or Alphatronic P40. Pertec used Honeywell Hall Effect switches for this keyboard. These Honeywell Hall Effect switches are marked "4A3B", "4A3A" and "6A1D" for the stabilizers.

As usual the base of the switch housing reads "MICRO USA" but there is no Micro Switch sticker anywhere on the keyboard and no Micro Switch marking on the PCB suggesting Pertec manufactured their own PCB and bought the switches from Honeywell. This keyboard has a "tweeter", an internal speaker which makes a noise when typing on the keys. There are two main PCC labels, one on the backplate, one on the inside including a total of eleven different serial numbers on labels, stickers and the case itself.