Advanced Qualification · A-002 Advanced components and circuits · A-002-009-006
In a frequency multiplier circuit, an inductance (L1) and a variable capacitor (C2) are connected in series between VCC+ and ground. The collector of a transistor is connected to a tap on L1. The purpose of the variable capacitor is to:
- Atune L1 to the desired harmonic
- Bby-pass RF
- Ctune L1 to the frequency applied to the base
- Dprovide positive feedback
Correct answer: A — tune L1 to the desired harmonic. From the official ISED question bank, verified word for word.
Why
A frequency multiplier creates output signals at multiples of the input frequency, such as doubling or tripling it. The full explanation — and one for every question — is in Pro.
Practise this section
Advanced components and circuits is section A-002 of the Advanced exam: Advanced components and circuits: semiconductors, amplifier classes, oscillators, mixers, filters and digital logic.
Drill A-002 — free, no account