Arachnid 1000 Series Information page 9

Diode Matrix
Each segment's switch contacts are connected to a printed
circuit card which is assembled to encircle the outer ring of
(The card is 2 1 / 2 " wide by 48" long when laid flat
switches.
prior to assembly).
The singles,
and white wires
of the 81 switches.
This printed circuit card contains an encoding diode matrix
which encodes each score into a plain binary word of 1,2,4,8,16
and 32. Drawing
A cableform connects this matrix to PL9
and triples are connected by red, blue
doubles
A common line joins all other contacts
respectively.
number SAD0121 illustrates this
of the Motherboard.
technique.