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File name noise.pdf

Noise Generator Strictly speaking, noise is a composite of a great number of signals at many, varying frequencies. It is a random quantity which generally has no regular or repetitive character. Although it is usually an unwanted quantity, noise may be used to analyze the performance of an audio system. A noise generator is, therefore, indispensable for much work in an audio workshop. Unfortunately, many amateur audio enthusiasts find the price of noise generator beyond their means. This is an affordable, small noise generator that is easy to build. White or pink noise at the flick of a switch Main parameters Frequency range Signal output Signal source Output voltage Attenuation Power supply Current drain 20-20000 Hz White noise or pink noise Pseudo random noise generator 2 Vp-p max About 10 dB lithium battery About 4.5 mA Parts list Resistors: R1, R3 = 39 K R2 = 18 K R4 = 5.6 K R5 = 10 K R6, R7 = 1 M R8 = 15 K R9 = 2.2 K R10 = 46.4 K R11 = 3.01 K R12 = 10.0 K R13 = 30.1 K R14 = 33 K R15 68 K R16 100 K R66 = 680 K P1 = preset potentiometer, 250 K Capacitors: C1 = 300 pF C2 = 82 pF C3 = 1 uF, 35V, radial C4, C9, C13-C15 = 0.1 uF C5 = 47 uF, 16V, radial C6 = 0.01 uF C7 = 0.015 uF C8 = 0.027 uF C10 = 10 uF, 16V, radial C11 = 10 uF, 35V, radial C12 = 100 uF, 16V, radial Semiconductors: D1= 1N4001 Integrated Circuits: IC1 = 4070 IC2 = 4006 IC3 = TLC272CP Miscellaneous: BT1 = lithium battery Type CR2032 with Holder for board mounting S1 = right angled slide switch with 1 Change over contact for board Mounting S2 = right angled slide switch with 1 On contact for board mounting