Instrumentation for the Farnsworth-Munsell 100-hue test

Standard Farnsworth-Munsell (F-M) disks and caps are numerically encoded in a two-digit, base-five, system using resistors and zener diodes connected to miniature jack plugs. When the subject orders the disks in the usual way, he connects the plugs to sockets that are in turn connected to an electronic processor. The various error scores are computed, and the error-versus-position graph plotted by a pen recorder, in a total time of between 0.5 and 2.5 min.