An anti-counterfeiting bottle includes a metal cap, a bottle body and a RFID tag. Embodiments of the circuit contain an oscillator circuit that generates and supplies an oscillating signal and a time delay circuit, which generates a time delay to signal the oscillator to shift frequency. A moving nut is coupled to the tuning screw and is guided between the at least two opposing guide surfaces to adjust a tension in the strings, and the moving nut includes a string connection point which is offset from the tuning screw.