This is a modification of a circuit that was shown in a National Semiconductor Databook.
This Circuit is said to be Low in distortion, But I haven't actually tested it to determine the Actual percentage. However the waveform looks very good.
Once you have built it, Set the frequency as desired using the "Frequency Control". Than using an Oscilloscope you can adjust for best waveform using the "Clip Control".
Lower Frequencies can be obtained by further Increasing the values of C1 and C2.
Higher frequencies are also possible, but the quality of the waveform will be determined by the "Slew Rate" of the IC.
Note: The Output is at 1/2 the Supply's Voltage. So an Output Blocking capacitor may be required when using this circuit.
About Square Waves and Speakers
Square waves are useful for many things, but they are NOT Good for Speakers.
Due to the Sharp Rise and Fall times of Square Waves, they try to make a speaker cone go from a full out position to a full in position. These continuous sudden changes in the speaker cone movement, will eventually Rip the coil from its form. Than the speaker produces a Fuzzy tone and eventually will quit all together!
This Square wave Effect is also produced when "Over Driving your Stereo", as that also produces Square Waves. More speakers are damaged in this way than by Excessive power. Under-Powered Amplifiers can be bad if you like loud music. Having "Power to Spare" on an Amplifier is good and reduces the possibility of Square Wave Distortion and Speaker Damage!
Good Quality Musical Instrument Speakers are Specially Designed to better handle Square Wave Distortion, Because most musical instruments produce a fair amount of it. However recorded music does not faithfully reproduce square wave distortion, so normally it isn't a problem for Home type speakers. However, Over-driving a Power-amp WILL definately produce Square waves and damage these types of speakers. Sometimes very quickly.
