The I/O board.

Documentation on the chips used by EBCS IO board.

Documentation (1)
CD40106.pdf	Hex schmitt triggers
TL071.pdf	Low Noise Single J-FET operational amplifiers
L7800.pdf	Positive voltage regulator (7805, 7812, 7815, ...).
BD140.pdf	PNP Silicon Transistor
BC237.pdf	NPN Epitaxial Silicon Transistor
BC557.pdf	PNP Epitaxial Silicon Transistor
TL071.pdfLow Noise J-FET Operational Amplifier

(1) Documentation publicly available on various constructor web sites and copied here for archiving.