long range stable fm transmitter

Posted on Feb 7, 2014

This is a long range stable FM transmitter circuit. The circuit is using a LM2950 5V voltage regulator IC comes in TO 92 transistor package, which will provide a stable 5V to the oscillator till the 9V battery runs down to 5. 5 volts, due to which the oscillator becomes frequency stable. The circuit is using two transistors, transistor Q1 is workin

long range stable fm transmitter
Click here to download the full size of the above Circuit.

g as an oscillator and Q2 is working as an RF amplifier and also separating the oscillator from the antenna due to which the circuit becomes more frequency stable. Coil L1 and L2 are air cored coils equal to 10 turns of 1mm enameled wire close wound on a 3mm form. The frequency of the transmitter can be adjusted with trimmer C4. The maximum output power can be achieved by adjusting the trimmer C5. A field strength meter or RF power meter will be required to set the transmitter on the maximum output power. Use 30 inch wire antenna for maximum range. Keep all the components as near as possible in the circuit. The maximum range of the circuit will be 2 KM or more in the open area.

Leave Comment

characters left:

New Circuits



Popular Circuits

Equalization Circuit
RF-powered sidetone oscillator
Charger Extends Lead-Acid Battery Life
5W 80M Cw Transceiver
10M Dsb Qrp Transmitter With Vfo Circuit
Final Project
capacitive sensor
Case Modding
Boost Led Driver With 1:3000 Dimming Ratio And Excellent Current Regulation
VHF FM Crstal Set Radios
Square Tesla Coil
Ridiculously Simple AVR AM Radio Transmitter
Strategic Dog Initiative
Distributed parameter type microstrip circuit