The Acorn A4 keyboard is a membrane type, without any additional electronics on it (apart from three LEDs). The membrane plugs directly into the motherboard, and is very fragile. The layout of the membrane can be seen in the picture below. Red is the top layer, black is the bottom layer and green is the keycap layout. This is produced from taking the keyboard apart and scanning the layers - click on the image for a highest resolution picture (75K). A drawfile (zipped, 470K) contains the individual scans superimposed so you can access each layer individually.
![[A4 keyboard membrane]](img/keyboard/1789x830.png)
Page by Theo Markettos (email at theo [at@] markettos.org.uk), last modified 2003-09-18
Return to Theo's A4 pages.