Introduction: Easy FM Transmitter
This an easy FM transmitter made with the PCB of a toy walkie talkie . It is easy to build and all you have to need is a walkie talkie having FM bandwidth.Here, i have hacked the walkie talkie's frequency to my own frequency . It's frequency is manually set to 102.5.
1 . A walkie talkie of FM band
2 . A LED (to be used as the power indicator)
3 . Microphone
4 . Some wires
NOTE: LED and microphone is usually available with in the walkie talkie
PUTTING ALL TOGETHER
1 . Open the walkie talkie an take out the PCB , LED , speaker and microphone
2 . cut of the wires to speakers (as FM transmitter does not need speaker to do something)
3 . Adjust the inductor L3 so as to manipulate the frequency (The frequency must be adjusted manually with trial and error method using a FM receiver . DO NOTE THAT IT DOES NOT INTERFERE WITH ANY OTHER FREQUENCY)
4 . Place the circuit in a suitable case and fix it firmly
5 . Connect the LED and microphone (if not connected)
6 . Supply an appropriate power to the circuit ( In this case it is 3V DC)
EXTENDING THE FREQUENCY
In order to increase the range of transmitting connect a telescopic antenna to the antenna outlet
(If needed you can amplify it using another electronic circuit)
The frequency that you assign to the FM must satisfy with the respective broadcasting rules prevailing in the country.
It should not cause any interference to other signals
The maximum range of the transmitter depends upon the circuit that is used
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