Try this circuit out for yourself, it's made especially to generate a pilot tone used in the C-QUAM AM stereo system, but could be used in other projects that call for a sine wave in the audio frequency range. Status: Working, but not applied to a C-QUAM transmitter yet.
Circuit Diagram
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Instead of being fed from the discharge pin 7 as in the usual astable 555 oscillator, pins connected to output pin 3 instead.
Oscillator on protoboard
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Scope Trace
The top trace is the 555 oscillator after filtering. The bottom wave is from a digital signal generator card.
