Super-PLAM (AM Empfänger mit PLL-Demodulator)

This circuit can be used to give quite a natural imitation of a vibrating string. An astable multivibrator consisting of transistors T 1 and T 2 produces the fundamental tone. As long as switch S is not operated, the two transistors T 3 and T 4 are conducting, and thus the multivibrator output is short-circuited.