In the video intermediate-frequency (IF) strip of a color television receiver, which types of frequency traps are commonly used to shape the response and reject unwanted components?

Introduction / Context:
Color TV IF strips must pass the desired video spectrum while rejecting the sound carrier, the color subcarrier image components, and adjacent-channel interference. Traps are frequency-selective networks added to notch out specific frequencies without unduly distorting the video passband.

Given Data / Assumptions:

• Receiver is a color TV with a standard video IF around 38.9–45.75 MHz (standard-dependent).
• Different traps (series, shunt, absorption) can be used.

Concept / Approach:

Shunt and series traps implement notch responses with different insertion behaviors. Absorption traps (loosely coupled resonators) absorb energy at unwanted frequencies to create a deep notch while minimally disturbing adjacent passband regions. In practice, designers mix these techniques to achieve the required response template.

Step-by-Step Solution:

Verification / Alternative check:

Service manuals and classic IF design texts show multiple trap types in one IF strip to precisely shape the response curve.

Why Other Options Are Wrong:

• Limiting to one trap type rarely meets stringent mask requirements.
• “None” contradicts standard IF design practice.

Common Pitfalls:

Believing a single trap type suffices; underestimating the role of coupling factor and Q in realizing deep, narrow notches without ringing.

Final Answer:

All of the above