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Quality FM Transmitter Save Rs. 100.00
Rs. 300.00
Rs. 200.00

Quality FM Transmitter

Quality FM Transmitter

by KNS Pvt Ltd
Save Rs. 100.00
Rs. 300.00
Rs. 200.00

Summary

The digital like sound quality that FM offers is the reason that many people prefer to have their own transmitting station in FM band. The Quality FM Transmitter can transmit a chosen music piece in the FM band. To receive its signals, any conventional FM radio receiver can be used. It provides an easy way to transmit less distorted, low noise music with in a range of about 200 meters.

Just build yourself a simple FM transmitter, plug in the input via mobile or any other source and off you go with your own radio channel.Sounds exciting right !!

Learning

Things which you can learn:
*Application of transistor as amplifier.
*Working of variable resistor and trimmers.
*Concept and implementation of VHF using LC tuning Circuit
*Concept and implementation of Frequency modulation and antenna matching network
*Gain and maximum power transmission

Product Description

The Quality FM Transmitter provides good signal strength up to a distance of 500meters with a power output of about 200 mW. It works off a 9V battery. The input to the transmitter can be given by various sources like mobile phones, mp3 players etc.

Working

The audio-frequency modulation stage is built around transistor BF494 (T1), which is wired as a VHF oscillator and modulates the audio signal present at the base. Using preset VR1, one can adjust the audio signal level. The VHF frequency is decided by coil L1 and variable capacitor VC1. By reducing the value of VR2, a greater power output can be achieved. The next stage is built around transistor BC548 (T2), which serves as a Class-A power amplifier. This stage is inductively coupled to the audio-frequency modulation stage. The antenna matching network consists of variable capacitor VC2 and capacitor C9. By adjusting VC2, maximum power transmission and signal strength can be attained at the receiver end.

Click To View Circuit Diagram

Click here to Download PDF

Cordless FM MIC Save Rs. 50.00
Rs. 200.00
Rs. 150.00

Cordless FM MIC

Cordless FM MIC

by KNS Pvt Ltd
Save Rs. 50.00
Rs. 200.00
Rs. 150.00

Summary

The Cordless FM Mic can be used as an FM transmitter. The frequency transmitted by the circuit is FM modulated and hence the voice at condenser microphone can be listened to through a standard FM receiver.

Learning

Things which you can learn:

*Concepts related to FM modulation and transmission.
*Application of NPN transistors as signal amplifiers.
*Application of the condenser mic as an input device.

Product Description

Build a simple circuit which can be used as a one-way walkie talkie. Use this kit to transmit your voice over FM and receive the sound in a standard FM receiver.

Working

The circuit of the Cordless FM Mic consists of a high-frequency air core coil (L1) with six closely wound turns of 25 SWG enameled copper wire on 4 mm diameter air former. The range of this transmitter can be enhanced by connecting a 30-60cm long wire as an antenna and changing the value of the 0.0015 micro Farad capacitor to up to 33 Pico Farad.

The range and transmitted frequency can be changed by increasing or decreasing the length of wire which is connected to a collector of NPN transistor 2N2369 (T2)via a capacitor. NPN transistor BC548 (T1) works as a condenser mic amplifier and T2 works as an FM oscillator and modulator by the help of other passive components. The main advantage of this transmitter is that it works off a 3V battery which can be easily obtained from two AA size pencil batteries.

Click To View Circuit Diagram

Click here to Download PDF