Q.Draw the block diagram and explain the various stages of AM transmitter.

An AM transmitter has two parallel signal chains that combine at the final stage: an RF (carrier) section that generates and amplifies the carrier, and an audio (modulating) section that amplifies the message. High-level collector modulation combines them and feeds the antenna. …

[!TLDR]

An AM transmitter generates a stable carrier (oscillator, buffer, multiplier, RF power amplifier) and amplifies the audio (mic, AF amplifier, modulating amplifier), then modulates the carrier at the power stage and radiates it.

The transmitter consists of two sections whose outputs meet at the power amplifier where modulation takes place.

RF (carrier) section:

1. Crystal oscillator: generates a very stable carrier of the required frequency using a quartz crystal, ensuring the transmitted frequency does not drift.
2. Buffer amplifier: isolates the oscillator from the following stages so that changes in load do not pull the oscillator frequency; it also amplifies the carrier slightly.
3. Frequency multiplier: raises the oscillator frequency to the final carrier frequency by multiplication (used when the crystal frequency is lower than the transmit frequency).
4. RF power amplifier: a Class-C amplifier that raises the carrier to the high power level needed for transmission; this is the stage at which modulation is applied.

Audio (modulating) section:

5. Microphone: converts sound into an electrical audio (modulating) signal.

6. Audio (AF) amplifier: a voltage amplifier that raises the weak microphone output.

7. Modulating (audio power) amplifier: raises the audio to the power level required to modulate the RF power amplifier.

Modulation and radiation: …