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...a signal generator and audio reference CD for technicians, hobbyists, musicians, teachers and other experimenters.

Wish you had a signal generator? Want to test audio equipment? Need a precise tone? Use RefCD!

RefCD contains a variety of signals which can be used to test and calibrate audio equipment, troubleshoot electronic designs and perform a range of simple demonstrations. The accuracy of the tones is limited only by the quality of the CD player used to reproduce the tracks. Frequencies from 20Hz to the 22KHz limit of a CD player can be reproduced with 16 bit resolution.

With RefCD, a CD player and an oscilloscope is all you need to perform a large number of tests and demonstrations. Add an audio amplifier and you can test small motors and and carry out demonstrations on the physics of sound (*). Some examples of tracks from RefCD and their uses are listed below.
Function Application
Pure sine waves Various uses
Musical notes (sine waves) Tuning instruments, play simple tunes (use a programmable CD player)
Frequency sweep, 1Hz-10KHz Frequencyresponse of amplifiers, test equipment, hearing tests
Amplitude sweep(1.000Khz) Linearity tests, hearing experiments
Signal in right channel only Channel separation test ofaudio equipment
60Hz "push/pull" sine or square wave Testing transformers, power intverters, motors, check tracking speed of CD players
Sine on right channel, Cosine on left channel Demonstrations of sine andcosine, 2 phase motors
1.000Khz on right, 999.0 Hz on left Demonstration of relative phase, test phase lock circuits, demonstration of interference of sound waves
1.000Khz AM and FM Demonstrate modulation, test demodulators

For more information and purchases, check out

*  This CD is intended for use as a signal/function generator, but some of the tracks on this CD are NOT meant to be played through speakers. Some of the tones, the low frequencies in particular, can very quickly burn out a typical speaker. Care must be used at all times when reproducing pure tones through an audio amplifier.

This web page and RefCD are Copyright 2000 by Daniel Koller.