Parts List: R1-2-4-5=270Ω R3 = 2.7Ω VR1 = 10KΩ Log. Pot. TR1 = 470KΩ Trimmer IC1-2 = LM388 C1 = 100uF/25V C2 = 100nF C3 = 10uF/25V C4-5 = 22uF/25V C6 = 47nF