A CB transmitter in 27MHz bandwidth can be built using this electronic scheme. The circuit is built using Motorola MC2833 integrated circuit - VHF transmitter with narrow band FM modulation and can be used as a wireless microphone.
Transmitter output power is about 10 mW (10 dBm), which, due to low efficiency, will result in effective radiated power less than 1 mW typical. Range of emitter is limited to 10 20 m
MC2833 circuits include a built-in microphone amplifier, an voltage controlled oscillator, and two auxiliary transistors used for frequency multiplication and amplification in RF. Depending on the desired output frequency, potentiometer P1 is used to adjust the microphone amplification and P2 is used for deviation adjustment. Because transmitter will only narrow band frequency modulation with maximum deviation of 5 kHz, is required a CB typical narrow band 27 MHz receiver.
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