Student stimulators transistorised out put 0, 25 dc in duration ., Two steps5 ro 1. 5ms frequency 5 to 100 c/s in 11 steps, Modes, Single, Repetitive or an external trigger, For 220v 50hz. Student electronic stimulator latest design frequency continuously variable from 0. 1hz to 100hz in 3 decades of 0. 1 to 1, 1 to 10 and 10 to 100 selectable through push, Button controls and one continuously variable control. Output voltage continuously variable ranging from none to 30v in two steps of 1 to 3 and 1 to 30, Selectable through a switch. Fixed pulse duration 1m secsingle & external trig. Single pulse facilitysensitive speaker to give audible indication or each outputhigh stability new circuitry minimises external interference. Research stimulator with r. F. Isolation unit provides rectangular pulse of controlled polarity, Amptitude 1. 5mv to 150v, Frequency 0. 1 to 10 kcs delay 10 micro sec to 1 sec & width 10 micro sec to 1 sec.