A simple rate meter and oscilloscope intensity modulator for single cell recording

Abstract

A simple circuit has been described which gives a meter reading proportional to the rate of cell firing. The circuit will trigger reliably on any signal exceeding 100 mV, and a trigger-level control is provided to enable triggering to be suppressed below a threshold level. An external recorder may be driven from the circuit. In addition the circuit provides a pulse which may be used to modulate the intensity of an oscilloscope trace each time the threshold is exceeded.