Question

Intermediate Frequency (IF) amplifier in TV receiver is used as

• A. Audio signal amplifier
• B. Video signal amplifier
• C. Power amplifier
• D. Tuned amplifier

Hint:

The IF amplifier stage provides the majority of the TV receiver's overall gain and selectivity, ensuring that even weak broadcast signals are boosted cleanly before demodulation.

Answer 1

The Correct Option is D

Step 1: Understanding the Superheterodyne TV Receiver:
In a superheterodyne TV receiver, the incoming RF signal is mixed with a local oscillator signal to produce a fixed, lower frequency called the Intermediate Frequency (IF). For PAL-D systems, the video IF is typically $38.9\text{ MHz}$ and the audio IF is $33.4\text{ MHz}$.

Step 2: Analyzing the Role of the IF Amplifier:
The IF amplifier must selectively amplify this weak IF signal while rejecting all other frequencies and adjacent channel noise. To achieve this, it uses resonant LC tank circuits tuned precisely to the IF band.

Step 3: Evaluating the Options:
Since the IF amplifier is designed as a frequency-selective bandpass amplifier using tuned LC circuits, it is classified as a Tuned amplifier (D).