FM Antenna Amplifier Circuit


Posted on Feb 6, 2014

With this technique, an extra cable to power the fm antenna amplifier is unnecessary. The RF signal and the DC current supplying the amplifier use the cable simultaneously. Check another FM antenna booster circuit diagram. The RF signal is however prevented by LC filters from flowing into the power supply. The amplifier works with either 50 ohm or 75 ohm


FM Antenna Amplifier Circuit
Click here to download the full size of the above Circuit.

antenna. It has a gain of 25 30 dB. MOSFETs are used to avoid the problem of crossmodulation or intermodulation. The circuit is divided into two parts. The first part is the active aplifier circuit which is normally installed very near the antenna. The second part is the power supply circuit which supplies current to the amplifier through the coax cable. After the fm antenna amplifier circuit is constructed, the power supply should be connected to it. You must then test the DC voltage in the cable. This must be between 15. 5 and 36. 6 volts. Then test the voltage between T5 collector and ground while adjusting the supply voltage. It must move from 3 to 24 volts. The emitter of T2 should be approx. 11. 4 volts. If the voltage at R4 is between 0. 7 and 2 volts, then the MOSFET is functioning properly.




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    Telephone DTMF decoder Display
    Tape recorder interface
    Rlc-oscillator
    Tremolo
    Infrared circuits related resources
    mc2833 fm transmitter circuit design electronic project
    how to build simple am transmitter
    Telephone call meter using calculator & COB
    Small low-frequency drift polarity switching synchronous detector circuit
    A volt DC power supply circuit



    Top