Single chip FM transmitter

An FM transmitter is a device that can transmit audio from an audio device as a radio signal. Doing so allows the audio to be picked up and played by an FM radio in the transmitter’s range. The FM (frequency modulation) device allows the waves to move in predefined frequencies so it can be identified by a radio tuned o this particular frequency range.

FM transmitters can be made in different ways. Circuitstoday alone has at least 5-6 articles dedicated to constructing these transistors.

Here is another method of building an FM transmitter, this one uses an IC.

Description

Here’s a single chip FM transmitter circuit using Maxim semiconductors IC MAX2606.

The MAX2606 is a compact, high-performance intermediate frequency VCO specially designed for wireless communication circuits. They have monolithic construction with low-noise and a low-power operation in a compact 6-pin SOT23 packing.

This low-noise IC features an on-chip varicap diode and feedback capacitances that avoid the need for external tuning components, making the MAX2606 perfect for portable systems. Only an external inductor is needed to set the oscillation frequency. In addition to this, an integrated differential output buffer is also there for driving a mixer or prescaler.

The MAX2606 can be operated from a single +2.8 V to +5.4V supply and consumes very less current. The chip can be operated from 45MHz to 650MHz.

In the circuit, the nominal frequency is set to 100 Mhz by inductor L1, (390nH). The left and right channel audio signals from your source are added by R3 and R4, and attenuated by the POT R2. R2 can be used as a volume control. POT R1 can be used to select a channel of transmission between 88Mhz and 108Mhz. Use the 80 cm long wire as the antenna.

FM Transmitter Circuit Diagram with Parts List.

Single Chip FM Transmitter
Single Chip FM Transmitter Circuit Diagram

Notes

  • Assemble the circuit on a good quality PCB or common board.
  • Use a battery for powering the circuit. It will reduce noise.
  • An FM antenna from an old radio is a better option than the wire antenna.

Our website contains more Radio Transmitter Circuits that you may like to read;

1. Stereo FM Transmitter

2. 200 Meter FM Transmitter

3. 2 Km FM Transmitter

4. FM Transmitter using UPC1651

5. Medium Power FM Transmitter

Author

21 Comments

  1. megha shyam

    how to tune the above FM transmitter to 100Mhz?

    • Seetharaman

      The maximum dissipation is around 500mw. say you can achieve around 0.5 to 1KM max. @ 100MHz.

  2. mallikarjun

    Dear sir,

    In this circuit used all components smd are through hole pls replay.

    Thhank you

  3. mallikarjun

    Dear sir,

    In this circuit used all components smd are through hole pls replay.

    Thhank you

  4. Crazy Guy

    Please explain how to make signals from me to the moon. I need a 400 GHz transmitter for control of lunar rover. PLEASE HELP! THE DEPARTMENT IS TO KILL ME!

    • OK pagle .You can use a sun direction to send the signals to the moon.Hope you are almost got your ans,,,,

  5. i want making a 60mhz to 80mhz fm receiver.please help me the subject of making inductor for this project.How can make the inductor these freequency.

    • Helo Rafeeq.Here’s a single chip FM transmitter circuit using Maxim semiconductors IC MAX2606. The MAX2606 is a compact, high-performance intermediate frequency VCO specially designed for wireless communication circuits. They have monolithic construction with low-noise and a low-power operation in a compact 6-pin SOT23 packing .Th1s low-noise IC feature an on-chip varicap diode and feedback capacitances that avoid the need for external tuning components, making the MAX2606 perfect for portable systems. Only an external inductor is needed to set the oscillation frequency.In addition to this, an

  6. Samuel Okello

    Please I have seen alot of your circuit diagrams,send for me a simple one which can cover 1km.thanks

  7. Seetharaman

    Hi SAWKAT nH means nano Henri,
    1H / 1000 is mH 1H / 1000000 is uH. 1H / 1000000000 is nH. 1H / 1000000000000 is 1pH

  8. I want the Department to send and receive wireless within 3 kelometer of the images and video, or pictures only, and are sent from the USB stick or mobile reception is on your computer or mobile, and be simple and inexpensive
    Please help me ….

  9. NAVAZ SHAREEF

    I want to construct an FM transmitter using SINGLE CHIP FM transistor between 170mhz to 220mhz

    Why I calculate the value of L1
    please help me??

  10. dharmendra

    sir
    can u send me componants, with chargable
    dbhattji.

  11. Pedro Rito

    Why you determinate the value of L1?

    I want to construct a FM transmitter with nominal frequency between 174 mhz and 216 mhz.

    Can you help me to calculate L1?
    reply to my e-mail.

    Thank you

  12. arunkumar

    Please mention the voltage for the condensor in the single chip(MAX2606) fm transmitter