Mini FM transmitter - 3 Volt FM Transmitter (bug)

The most powerful circuit we've seen that operates on such low voltage (just two AA batteries). A range of 150 to 200ft can be expected and, given a good antenna and FM receiver, over 1 mile can be expected. An external power supply can be used up to 9 volts. Transmits to the FM radio band. Teaches basics of transmitters. Microphone is included. Specifications: L: 1-3/4" W: 3/4" H: 1/2". Requires 2 AA batteries (holder included, not shown in picture). Transmission frequency is user selectable. Transmission can be listened to on any FM radio.