Advanced Qualification · A-002 Advanced components and circuits · A-002-006-007

Which of the following classes of amplifier would provide the highest efficiency in the output stage of a CW, RTTY or FM transmitter?

1. A Class C
2. B Class AB
3. C Class B
4. D Class A

Correct answer: A — Class C. From the official ISED question bank, verified word for word.

Why

Class C amplifiers are the most efficient choice for constant-envelope signals like CW, RTTY, or FM because they conduct for less than half of the input cycle, wasting very little energy as heat. The full explanation — and one for every question — is in Pro.

Practise this section

Advanced components and circuits: semiconductors, amplifier classes, oscillators, mixers, filters and digital logic.

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