The A13-75 will isolate and amplify any stimulus signal - square pulse, sine, ramps, etc., and control for constant current or constant voltage. A fully protected, direct-coupled output prevents damage from overloads or shorts, and the power supply is completely isolated from the stimulus-signal inputs. A high-speed reed relay electrode shunt provides for stimulus presentation and electrode disconnect and shorting to eliminate tissue charge buildup. No matter what signal source is used, the isolator's stimulus output can be controlled for either constant (feedback regulated) voltage or current. The voltage of the stimulus signal fed into the input will determine either the voltage or the current of the output. 

The 3 ranges of current setting will produce constant current outputs of 0 to 100 microamps, 0 to 1 milliamp, and 0 to 10 milliamps. The input voltage determines the output current in this mode. If the midrange were selected (which produces 100 microamps per volt) and a stimulus complex in the range of 0.5 volts were introduced to the input, the output would be the same stimulus configuration ("waveform") controlled for a constant current in the range of 50 microamps.

In the voltage mode, the unit puts out a constant voltage at the rate of 1 volt per volt input (unity gain); or 10 volts per volt (x10); or 100 volts per volt (x100). If the midrange is selected and the stimulus signal voltage is 0.5 Volts, the output will be the same signal form at a voltage of 5 volts. Stimulus sources may be synthesized analog signals from signal generators, oscillators, or non-isolated stimulators; or they can be recorded signals from analog tape, digital tape or a computer via analog to digital converters.