The transmitter goes together in about 10 minutes, and is small enough to fit in the palm of your hand. Depending on the antenna, it can send voice and music across the room, or across the street.
The oscillator is the heart of the transmitter. It has four leads, but we only use three of them. When the power is connected to two of the leads, the voltage on third lead starts jumping between 0 volts and 5 volts, one million times each second?
The oscillator is built into a metal can. The corners of the can are rounded, except for the lower left corner, which is sharp. This indicates the where the unused lead is. The lead is there to help hold the can down firmly on the printed circuit board, but it is not connected to anything inside the can.
The other main part is the audio transformer . In this circuit it is used as a modulator. The modulator changes the strength of the radio waves to match the loudness of the music or voice we want to transmit.
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