Tag Archives: FM Transmitter

Frequency Modulated Oscillator (for FM Transmitter)

Posted on January 2, 2012 by Rust

An oscillator can be built using LC (inductor-capacitor) tank circuit. When we vary the capacity of the capacitor in LC tank circuit then the frequency of the oscillator will vary according to capacitance change.  The idea of this modulator is … Continue reading →

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50 kHz FM Optical Receiver

Posted on May 23, 2011 by Rust

Frequency modulation (FM) can be used to transmit analog voltage level signal with good noise immunity. The transmission itself  might employs different methods, and this circuit uses free air optical medium. This optical receiver circuit is built using a L14G2 … Continue reading →

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Wireless Telephone Line Spy

Posted on July 12, 2010 by Rend
PHONE BUG

This is a phone bug circuit. This wireless telephone line spy circuit can be used to transmit the phone conversation to a nearby FM radio. This circuit must connected to a normal phone line.  Here is the schematic diagram of … Continue reading →

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