Simple FM transmitter with a single transistor

This simple FM trasmitter works on 1.1-3 V supply (1.8 mA current @ 1.5 volts). This circuit gives around 30 meters range and has a built-in elecret microphone.

FM Transmitter

The range of the transmitter when running at 9V is about 300 feet. Running it from 12V increases the range to about 400 feet.

1.5 Volt Tracking Transmitter

Operates from 87-109MHz. The current draw for this tracker is 3.7mA, so the 1.5V button cell will last a while. My experimental version was tuned to 87.6MHz and worked as expected on only 1.5 volts.

Low Power FM Transmitter

This circuit operates from 9V battery and transmits FM signal at frequency range around 90-108 MHz. This circuit can take microphone or line level signals for modulation.

RC2546T- 3km VCO FM Transmitter

The is a very small and fully optimized FM transmitter. It is built on a 2" x 2" single sided, high quality PCB for best result. This can be used as a miniature FM BUG.

RC2547T-FM Digital PLL FM Transmitter

Fully digital PLL synthesizer controlled ensuring highest degree of frequency stability. You can choose in between 21 channels from 88MHz to 108MHz full FM band, in 1MHz step. A seven-segment digital channel display shows the channel number.

4W FM Transmitter

This is a small but quite powerful FM transmitter having three RF stages incorporating an audio preamplifier for better modulation. t has an output power of 4 Watts and works off 12-18 VDC which makes it easily portable.

Another Miniature FM Voice Transmitter

This is another easy-to-build miniature transmitter that uses a minimum of parts. Construction is straight forward and non-critical. Although this design uses a 3-volt power source (such as a lithium coin or button cell), a 9-volt battery can be used.

FM Band Monoaural Transmitter

FM Telephone Transmitter