we drive the Hall probe with ac current and measure the voltage with lock-in amplifier but the problem is that after some time the probe does not function(no current passes through it). Hall probe is driven with the alternative current from the sine output of the lock-in and i max is...
In quantum mechanics lab our frequency meter shows ~50 Hz when it is plugged into a device which is not turned on. Is this a problem or an effect that I don't know? :rolleyes: