Advantages of superheterodyne receivers: Compared to tuned radio frequency (TRF) receivers, which of the following is the main advantage of using superheterodyne receivers?

Introduction / Context:
The superheterodyne architecture is the dominant receiver design in radio communications. It was developed to overcome the limitations of tuned radio frequency (TRF) receivers, particularly when operating at higher frequencies where selectivity becomes a challenge.

Given Data / Assumptions:

• TRF receivers rely on multiple RF tuned stages.
• Superheterodyne receivers use frequency conversion to a fixed intermediate frequency (IF).
• IF stages provide consistent filtering and amplification.

Concept / Approach:

By converting all signals to a common IF, superheterodyne receivers simplify the design of sharp filters. This improves selectivity, especially at high frequencies, while TRF receivers struggle to maintain consistent tuning and narrow bandwidths across the spectrum.

Step-by-Step Solution:

Verification / Alternative check:

Historical adoption of superheterodyne receivers in AM/FM broadcasting and communications demonstrates their superior selectivity as the main advantage.

Why Other Options Are Wrong:

• High gain and sensitivity: possible with TRF as well, not unique to superhet.
• Stability: LO drift can cause instability; not a primary advantage.
• Noise suppression: depends more on modulation/demodulation, not core architecture.
• Lower cost: TRF sets were actually simpler and cheaper.

Common Pitfalls:

• Confusing sensitivity with selectivity.
• Assuming superhet suppresses noise inherently (it does not).

Final Answer:

Better selectivity at high frequencies