Which organisation issues amateur radio licences in the UK?
Ofcom Ofcom, the UK communications regulator, issues every amateur radio licence. The RSGB runs the exams and tells Ofcom when you pass, but the licence itself comes from Ofcom.
How often must you confirm to Ofcom that the details on your licence are still correct?
At least once every five years Your licence stays valid for life, but you must confirm your details at least once every five years. If you move or change your name, you also have to tell Ofcom straight away.
Which of these is allowed under an amateur radio licence?
Telling another amateur how you built your new antenna The amateur licence is for self-training in radio and is non-commercial. Talking about your own station and antennas is exactly what it’s for. Business use, advertising and music are not allowed.
When does the licence allow a Foundation licensee to send messages in a secret code (encryption)?
When controlling an amateur satellite Encryption isn’t allowed, apart from two cases: at the direct request of a User Service, or to control amateur satellites. Morse code isn’t a secret code, because anyone who learns it can read it.
A 12 volt supply is connected across a 4 ohm resistor. What current flows?
3 A Ohm’s law says current equals voltage divided by resistance, I = V ÷ R. So 12 V ÷ 4 Ω = 3 A.
A radio draws 2 amps from a 12 volt supply. How much power does it use?
24 W Power equals voltage times current, P = V × I. So 12 V × 2 A = 24 W.
Which of these materials is a good conductor of electricity?
Copper Metals such as copper and brass let electrons flow easily, so they’re good conductors. Glass, rubber, ceramics and plastics are insulators.
In a simple transmitter, which stage sets the frequency the transmitter operates on?
The oscillator The oscillator generates the radio frequency and so sets where the transmitter operates. If it’s set wrongly, you could end up outside the amateur band and interfere with other users.
What can happen if an FM transmitter uses too much frequency deviation?
It causes interference on nearby channels Too much deviation makes the FM signal wider than it should be, so it spills over into the channels next to it. Too much amplitude modulation on AM causes the same kind of problem.
Why is coaxial cable the most widely used feeder?
Its screen helps keep signals in and interference out Coaxial cable has a centre conductor surrounded by a screen. The screen helps stop RF getting into or out of the cable, which is why coax is so widely used. It’s unbalanced, and like all feeders it has some loss.
Roughly how long is a half-wave dipole for the 2 metre band?
About 1 metre A half-wave dipole is about half a wavelength long. On the 2 metre band the wavelength is about 2 metres, so the dipole is about 1 metre from end to end.
You measure a high SWR at your transmitter. What does this most likely show?
A fault in the antenna or feeder A high SWR means the antenna isn’t matching the feeder and transmitter, so power is reflected back. Measured at the transmitter, it points to a fault in the antenna or feeder, not the transmitter. A very high SWR can damage the transmitter.
How do most long-distance HF contacts happen?
The signal is refracted back to earth by the ionosphere On HF, most long-distance contacts rely on the ionosphere, layers of ionised gas about 70 to 400 km up. It bends signals back down to earth, which can give world-wide contacts. How well this works changes with frequency, time of day, season and solar activity.
You want to increase your range on 2 metres, for both sending and receiving. What usually helps most?
Raising the antenna higher VHF signals travel not much beyond line of sight, so height matters a lot. A higher antenna improves both transmit and receive, while more power only helps the signal you send.
Which modes are most likely to cause interference to a neighbour’s TV, radio or phone?
AM and SSB AM and SSB are the modes most likely to cause problems for nearby equipment. FM and some HF data modes are the least likely. The more power you run, the more likely interference becomes.
Your transmissions are getting into a neighbour’s TV. Where should a filter or choke be fitted?
As close to the TV as possible Filters and chokes on the mains or antenna leads can make equipment more immune to strong signals. They work best fitted as close to the affected device as possible.
Using the phonetic alphabet, how do you say the letters G and K?
Golf Kilo In the international phonetic alphabet, G is Golf and K is Kilo. Amateurs use it to spell call signs clearly, especially when signals are weak.
What should you do before calling CQ on a frequency?
Listen first, then ask if the frequency is in use Always listen first, because someone may already be using the frequency. Then ask if it’s in use before you call. Even if you can’t hear anyone, another station may be talking to someone you can’t hear.
Someone has had an accident involving electricity in your radio shack. What should you do first?
Switch off the power The first action is to switch off the power. Don’t touch the casualty until the power is off, or you could be electrocuted too. That’s why the station should have a clearly marked master switch that others know about.
You lean a ladder against a wall to reach a point 8 metres up. How far from the wall should the foot of the ladder be?
About 2 metres A ladder should be at a 4:1 angle: 4 units up for every 1 unit out from the wall. For 8 metres up, that’s 8 ÷ 4 = 2 metres out. The ladder should also be secured so it can’t slip.
United Kingdom · Licence exam