Abstract: An apparatus for testing a coin provides first, second, and third digital signals respectively indicative of the coin's metallic content, diameter, and thickness. A microprocessor-based control circuit identifies the coin as being one of a number of known coins in response to the digital signals. If the coin does not match any of the known coins, it is identified as a false coin, for example, a slug or foreign money.

Abstract: A matrix switch system is described with which a large number of communication lines can be interconnected. The lines are arranged in multiplex groups which are in turn sampled by multiplexers. The multiplexers in turn are coupled to matrix lines which intersect at connectable crosspoints. A common timing signal with a predetermined minimum number of time slices is used to reconfigure the system during each time slice and form the desired line connections through the multiplexers and crosspoints for signal transfer. A technique is described to allocate time slices for the various connections of the lines and minimize matrix lock conditions.