One Transistor FM Transmitter:  (circuit / schematic added 2/03)

Quality FM Transmitter:  (circuit / schematic design added 6/06)

Stereo FM Transmitter:  AN-543-StereoFMTransmitter-Analog Device Application Notes  (app note added 10/06) 

Subcarrier Adapter :  Listen to those hidden FM transmissions  (added 2/06)

Synchronous oscillator converts audio video to FM:  07/22/99 EDN Design Ideas  / (added 6/06) 

Three Transistor FM Radio Bug:  (electronic Circuit / Schematic added 10/04)

Two Transistor FM Transmitters #2:  (design added 8/03)

Two Transistor FM Transmitters:  (circuit / schematic design added 6/06)

Waveform Generator Demodulates FM Signals:  10/10/96 EDN-Design Ideas / (added 11/05) / The circuit in Figure 1 uses the phase-detector signals of a precision waveform-generator IC to perform FM demodulation. In a standard application, the IC's phase-detector input and output synchronize the chip's output frequency to that of an applied signal. If the signal is FM, you can extract the demodulated signal from the phase-detector output.   The waveform generator IC's phase-detector input (PDI) typically receives the phased-lock signal. The phase-detector output (PDO) then produces a duty-cycle-modulated train of rectangular current pulses that alternate between 0 and 500 mA. The duty cycle approaches 0% when PDI and the chip output (equivalent to the internal oscillator output) are in phase, 100% when they differ by 1808, and 50% as they approach....