The 'Keeler Polygraph' Model 302 shown here is one of Keeler' earlier instruments, dating back to 1953. This instrument was manufactured by 'Associated Research' of Chicago, Illinois and utilizes seven batteries, along with an AC power source. It is housed in a steel case with wrinkle finish and chromium trim. The cover is attached to the case with slip hinges allowing the cover to be removed.
The chart drive unit is powered by a synchronous motor at speeds of either six or twelve inches per minute. There are four recording pens, the lower pen and its associated controls comprise the pulse-blood pressure unit, while the longer pen records electrodermal variations. Located above the electrodermal pen is the pen for recording respiration changes, and at the top of the panel is the stimulus marker pen actuated by means of a flexible cable attached at the lower left of the panel. At the center of the panel is a standard sphygmomanometer, used as a guide to proper inflation of the blood pressure cuff.
Back to History Page