Schematics
The signal is continuously monitored by the input amplifier. In its initial state, the electronic switch is closed. In this state, the incoming signal is duplicated on two paths which lead to the input of the 2 entries of a difference amplifier. Since the two signals are equal, the output signal is zero.
On contact with a taste hair, a large offset is seen by the contact detector. A delay circuit opens the electronic switch after a delay and during 2-5 seconds. During this time, the difference amplifier sees the incoming signal (A channel) minus the signal stored in the capacitor (B channel), thus compensating the voltage offset.
