2B-SUPER SIMPLE TRANSMITTER
With the help of this project you can send message to a person sitting at a distance. You can also use this as a bugler alarm as well as send information to your neighbour when you are at danger. You can use your radio as an amplifier of this project.
TECHNICAL DESCRIIPTION AND WORKING:-
This project has been developed and successfully tested OK in TV Engineer Technical Lab.
Now a days you find Transmitter circuits of various types, but unfortunately these don’t work successfully. Here we are giving a circuit of a Super Simple Transmitter. The range of the transmitter is 50 meters, yet the reception is excellent. The circuit employs a medium wave antenna coil and only one transistor [TR1 BC 148]. It can be operated with a DC supply of 3V to 9V. The current consumption of the circuit is very low as only one transistor is employed in the circuit. Take the transmitter far away from your radio set and speak, your family member will listen to your voice. You will be surprised.
The transistor BC 148 is used as a common emitter amplifier. The base biasing of the circuit is done through R2 47k resistance while the collector positive biasing is done directly through positive line. The audio signal is fed to the base of TR1 through the condenser microphone, and C1 10 mfd. To incresase the signal strength of the transmitter , make the ferrite rod back and forward till you get the best reception in your radio.
The complete project can be fitted in a plastic cabinet after assembling on a general purpose PCB [ Multi purpose PCB]
Remember to connect the antenna coil output to the TV antenna as shown in the circuit.
PRECAUTIONS WHILE ASSEMBLING THE PROJECT:-
- Check all the components as per the circuit specification.
- Check collector, emitter and base of transistor before soldering.
- Also check for dry soldering and short circuit.
LIST OF COMPONENTS:
CONDENSER MIKE 1
TRANSISTOR TR1-BC148 1
C3 .01 mf 1
C2 470pf 1
C1 10 mfd/16V 1
R1 10K 1
R2 47K 1
MW WAVE ANTENNA COIL 1
FERRITE ROD 1
MULTIPURPOSE PCB 1
PLASTICE CABINET 1