The amplified voice signals from T1 collector gets effectively modulated over the T2 high frequency carriers waves and this modulated signal is applied to the base of T3 for enriching it with high current. Together this stage forms a regenerative oscillator which resonates in the range of 50 to 200MHz depending on the setting of the relevant LC tank components settings and values. This amplified signal is fed to the base of T2 which basically forms a frequency generator stage with the help of L1, C4, C5 and C3. The MIC converts the voice signals into electrical signals which is further amplified into high amplitude low current signals by T1. The operating principle of this powerful little transmitter can be understood from the following points: The Transmitters: First you will have to construct two of these identical transmitter circuits as shown below: Circuit Diagram How the Transmitter Works. The main objective here is to get a reasonable distance of wireless communication facility. The range of a single transistor circuit cannot be over 30 meters. The minimum distance this unit can cover is 50 to 100 meters. With this special patented design you can enjoy communicating with your friends in your multistorey apartment, across the highest number of floors. This enhances the power output of the transmitter to a great extent, approximately 4 times more than the single transistor version. Here the design incorporates a 3 transistor design along with a center tap antenna coil. Want to learn how to build a small transceiver circuit? The following post will walk you through all the details:Īs you can see the design is different from the usual single transistor concepts. In this post we try to design a walkie talkie using discrete transmitter modules and then tune them to different frequencies such that the units are able transmit and exchange the conversation across both the sides without interfering with their own receive modules.įor the FM transmitters we select the design which was earlier discussed in our wireless speaker circuit, the main reason being its ability to produce high power output, which enables the circuit to transmit the data over much longer distances compared to the other smaller FM transmitters designs. In one of my earlier post we comprehensively learned the making of a compact walkie talkie design, however I found that many new hobbyists and school students found the design difficult to adjust and succeed due to its rather complex and the associated strict parameters,
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