Advanced Qualification · A-005 Transmitters, modulation and processing · A-005-001-002
How is positive feedback coupled to the input in a Colpitts oscillator?
- A Through a capacitive divider
- B Through a tapped coil
- C Through a neutralizing capacitor
- D Through a link coupling
Correct answer: A — Through a capacitive divider. From the official ISED question bank, verified word for word.
Why
A Colpitts oscillator uses two capacitors connected in series across an inductor to create a capacitive divider, which splits the voltage and feeds a portion of it back to the input to sustain oscillation. The full explanation — and one for every question — is in Pro.
Practise this section
Transmitters, modulation and processing: AM, FM, SSB, keying, speech processing, and the numbers behind occupied bandwidth.