Am Transmitter Circuit Diagram

The circuit is in two halfs an audio amplifier and.

Am transmitter circuit diagram. There are many suppliers such as an audio transformer this is a 1000 ohm to 8 ohm audio transformer such as radio shack 273 1380. Am transmitter block diagram the transmitter s output amplifier circuit is shown in figure 1. Since its intended purpose was as a converter for superheterodyne receivers its output power capability is quite low. The tank circuit l1 and vc1 is tunable from about 500khz to 1600khz.

The circuit is in two halfs an audio amplifier and an rf oscillator. These components can be used from an old mw radio if available. The frequency of the rf signal can be determined by the oscillator coil l1 and variable capacitor vc1. Circuit description the heart of this circuit is a fet bfw10 t1 which works as a feedback oscillator.

This is the simple and low cost am transmitter schematic diagram built using transistor bc109c. Use a 30 cm long insulated copper wire as the antenna. Here is a low cost good stability rf am transmitter which uses only one fet. This ircuit is deliberately limited in power output but will provide amplitude modulation am of voice over the medium wave band.

Am transmitter circuit diagram. In practise about 3 milliwatts into. Mini am transmitter this is the simple and low cost am transmitter schematic diagram built using transistor bc109c. Radio receiver working principle.

The oscillator is built around q1 and associated components. In figure 1 there are three radio stations each broadcasting at a different wavelength each station is broadcasting a radio signal consisting of a carrier wave and an audio signal. Our transmitter will need these parts. A generic printed circuit board i used radio shack s 276 159a but any general purpose printed circuit board will do.

It is illegal to operate a radio transmitter without a license in most countries. Use a 200uh inductor for the l1 in the tank circuit. A one megahertz crystal oscillator this is a crystal clock oscillator such as those used in computers. This marvel of engineering is at the same time an oscillator mixer and amplifier all in one valve structure.

The circuit is in two halfs an audio amplifier and an rf oscillator. The amplifier circuit consists of two of the mallory circuits connected in a push pull configuration with a coupling transformer acting as both. This low cost am transmitter is tunable from 10 to 15 mhz with the help of j gang condenser vc1 which determines the carrier frequency of the amplitude modulation transmitter in conjunction with inductor l1. The transmission frequency can be adjusted using the variable capacitance c3.

The frequency trimming can be done with vc2.