Practice Licences · 1 min
Practice: radio basics
Ten questions on how radio works, written for Learn. Press a question to see the answer.
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These questions are written for Learn, not taken from any exam pool. They cover ideas every entry-level exam expects you to know.
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01What does "kHz" measure?
Frequency, in thousands of cycles per second.
02Which travels further at night on medium wave: groundwave or skywave?
Skywave, reflected by the ionosphere after dark.
03In FM, what changes with the sound?
The carrier's frequency.
04What is a call sign for?
Identifying a station to anyone who hears it.
05Roughly what wavelength is a 6,000 kHz signal?
About 50 metres (300,000 divided by the frequency in kHz gives metres).
06Why does shortwave reception change through the day?
The ionosphere changes with sunlight, altering which frequencies it reflects and absorbs.
07What is a band plan?
An agreed division of a band by type of use, such as Morse, voice and data.
08Can an amateur operator accept payment for transmitting?
No.
09What is a QSL card?
A card confirming that a station was heard or a contact was made.
10What does modulation do?
It changes a carrier so it carries information.