Basic Qualification · B-003 Station assembly, practice and safety · B-003-011-010
The DC power to the final stage of your transmitter is 200 watts and the RF output is 125 watts. What has happened to the rest of the power?
- AIt has been dissipated as heat
- BIt has been used to provide greater efficiency
- CIt has been used to provide negative feedback
- DIt has been used to provide positive feedback
Correct answer: A — It has been dissipated as heat. From the official ISED question bank, verified word for word.
Why
When your transmitter takes in 200 watts of direct current but only sends out 125 watts of radio frequency energy, the missing 75 watts does not vanish; it turns into heat inside the amplifier components. The full explanation — and one for every question — is in Pro.
Practise this section
Station assembly, practice and safety is section B-003 of the Basic exam: Building a station safely: power supplies, grounding, RF exposure, lightning, feedline routing, and what a transmitter, receiver and transceiver actually do.
Drill B-003 — free, no account