According to its author, this device indicates the amount of force applied to the sensors. The greater the force applied to the sensors, the louder the sound emitted from the speaker. The sensors are formed by two iron bars or another metal with a diameter of 2 cm (to facilitate the application of force). The procedure for using this device is simple: one takes the sensor electrodes, one in each hand, squeezing as hard as possible. The sound emitted by the speaker will be all the higher (higher frequency) the greater the strength. The 22 k trimpot allows you to adjust the device's operating point. The components are common, the transistor can be of any PNP type for general use and the output transformer is of the miniature type used in transistorized devices, with at least 1k of primary impedance.
