Am Radio Transmitter Circuit Diagram

The transmitter legally operates with micro power and will not set any distance records but unlike simpler designs the frequency stays put and the fidelity is excellent.

Am radio transmitter circuit diagram. The circuit is in two halfs an audio amplifier and an rf oscillator. Although the schematic looks somewhat complex the. These components can be used from an old mw radio if available. The circuit use a compact three transistor regenerative receiver with fixed feedback.

The circuit is in two halfs an audio amplifier and an rf oscillator. All general purpose transistors should work in this circuit you can use bc549 transistors for this circuit. The audio output from condenser mic is preamplified by transistor t3 bc548. The oscillator is built around q1 and associated components.

The tank circuit l1 and vc1 is tunable from about 500khz to 1600khz. It is similar in principle to the zn414 radio. Follows fcc regulations and still produces enough amplitude modulation. Where resistors r1 and r2 are in ohms capacitor c1 is in microfarads and frequency f is in hertz.

This am radio transmitter can transmit audio sound to your backyard. Notes it is illegal to operatea radio transmitter without a license in most countries. The audio output from t3 is further amplified by transistor t2 bd139 which modulates the rf amplifier built around transistor t1 by varying the current through it in accordance with the audio signal. A block diagram representing various stages of a basic continuous wave radio transmitter.

A condenser microphone is used for speaking. But it may increase the complexity of the circuit. The carrier wave is then amplified by the radio frequency rf power amplifier to the desired output wattage. This signal is called the carrier wave.

It is illegal to operate a radio transmitter without a license in most countries. Original am micropower transmitter. Following the action in figure 6 the oscillator creates an ac sine wave at the desired frequency. This ircuit is deliberately limited in power output but will provide amplitude modulation am of voice over the medium wave band.

A simple am transmitter circuit with diagram and schematic. This circuit is deliberately limited in power output but will provide amplitude modulation am of voice over the range 500khz to 1600khz with values shown. This is the simple and low cost am transmitter schematic diagram built using transistor bc109c. The circuit is in two halfs an audio amplifier and an rf oscillator.

The am radio transmitter does not use any modulator transformer. The oscillator is built around q1 and associated components. This is the simple and low cost am transmitter schematic diagram built using transistor bc109c. This frequency can be changed by simply replacing r2 with a variable resistor or c1 with gang capacitors.

Low range am radio transmitter circuit diagram.