coll circuit

Browse » home» fm » transmitter » upc1651 » using » FM transmitter using UPC1651

---

FM transmitter using UPC1651

Here is the circuit diagram of an FM
transmitter using the IC UPC1651. UPC1651 is a wide band UHF Silicon
MMIC amplifier. The IC has a broad frequency response to 1200MHz and
power gain up to 19dB.The IC can be operated from 5V DC.
The audio
signals picked by the microphone are fed to the input pin (pin2) of the
IC via capacitor C1. C1 acts as a noise filter. The modulated FM
signal will be available at the output pin (pin4) of the IC. Inductor
L1 and capacitor C3 forms the necessary LC circuit for creating the
oscillations. Frequency of the transmitter can be varied by adjusting
the capacitor C3.Circuit diagram with Parts list.


Notes.

• The circuit can be assembled on a Vero board.
• Inductor L1 can be made by making 5 turns of 26SWG enameled copper wire on a 4mm diameter plastic former.
• A ¾ meter insulated copper wire can be used as the antenna.
• Do not give more than 6V to the IC.
• Mic M1 can be a condenser microphone.