IC tremelo

7-62 elektor july/august 1980 T R3 a D C215 C4 C5 BC 177B IZ=1 0 am Ems 105 R8 15VR5R6P3 P2 50k 50k logU log 15 V 15 14 11 R12 270k C6. C.L.R13 7100n 10n C8 1=1 77p 80589 7815 degree of balance can be adjusted with P3 (to produce the Lesley effect). Little needs to be said about the power supply. The 7815 voltage regulator solves all the problems. It is not advisable to use an unstabil- ised supply as the modulation in the circuit would cause current fluctuations on the supply line. This will then cause deterioration of the modulating sinewave. The supply transformer should have a secondary winding of 15 . . . 18 volts at about 120 mA. The voltage regulator requires a heatsink in the form of an aluminium plate of about 10 cm2 . T. Stiihr Many of the familiar tremolo effect circuits (periodic amplitude modu- lation) suffer from three main disadvantages. Both distortion and modulation deviation frequently occur and the modulation fre- quency range is sometimes limited. The following...