Basic Qualification · B-003 Station assembly, practice and safety · B-003-001-001
To be most effective, where should a low-pass filter be connected in an HF station without an external power amplifier?
- A As close as possible to the transceiver output
- B Between the SWR meter and the antenna tuner
- C Between the antenna tuner and the antenna switch
- D As close as possible to the antenna switch output
Correct answer: A — As close as possible to the transceiver output. From the official ISED question bank, verified word for word.
Why
A low-pass filter stops high-frequency signals from escaping your radio, and placing it as close as possible to the transceiver output ensures these unwanted signals are blocked before they travel down the cable. The full explanation — and one for every question — is in Pro.
Practise this section
Building a station safely: power supplies, grounding, RF exposure, lightning, feedline routing, and what a transmitter, receiver and transceiver actually do.