We need to measure the impulse response of the EEG amplifier we use in our lab. We don't have so much equipment but, luckily, we have a pulse generator for delivering small electrical pulses with a given current amplitude to subjects for performing tests on pain. I was thinking of using this generator for measuring the IR or the amplifier. My plan is to a 100 Ohm load to simulate skin conductance and then use a voltage divider to bring the voltage within the micro Volt range that can be measured with EEG equipment. Is there anything else that I might need to consider?
“Impulse” response is hard to measure in practice. It’s more commonly calculated as the derivative of the much more practical step response.
It’s possible, though somewhat risky, to use a nerve stimulus generator to generate the step. After all those things can produce >400V while your EEG amplifier maxes out at <<100mV. Adjusting the current and using a divider to protect the amplifier a ~1mV step should be possible.
But, your stimulator does not generate steps, just pulses. So you would likely have to max out the duration and deal with a bit more complicated math.
It might be much more practical/easier to buy/put together a simple slow square wave generator with a calibrated voltage output.