Radio Theory Flashcards
Range of frequencies and wavelengths of HF band?
3 MHz - 30 MHz
100m - 10m (decametric)
Range of frequencies and wavelengths of VLF band?
3 kHz - 30 kHz
100km - 10km (myriametric)
1 KHz=
1 MHz=
1 GHz=
1 KHz= 1000 Hz
1 MHz= 1 000 000 Hz
1 GHz= 1 000 000 000 Haz
What is the formula to find frequency?
What units must each be in?
F= C/W
Frequency in Hz
Speed of light in m/s
Wavelength in meters
Range of frequencies and wavelengths of UHF band?
300 MHz - 3 ghz
1m - 10cm (decimetric)
Range of radio frequencies (lowest to highest)
3 kHz - 300 ghz
What is the speed of light per second?
300 000 000 m/s (3x10p8 m/s)
162 000 NM/s
Range of frequencies and wavelengths of MF band?
300 kHz - 3 MHz
1km - 100m (hectometric)
Mnemonic to remember frequency bands?
Very Lovely Maidens Have Very Useful Sewing Equipment
Range of frequencies and wavelengths of EHF band?
30 ghz - 300ghz
1cm - 1mm (millimetric)
Range of frequencies and wavelengths of LF band?
30 kHz - 300 kHz
10km - 1km (kilometric)
Range of frequencies and wavelengths of VHF band?
30 MHz - 300 MHz
10m - 1m (metric)
What is a transducer?
A device that converts energy from one type to another
Range of frequencies and wavelengths of SHF band?
3 ghz - 30 ghz
10cm - 1cm (centimetric)
What is Amplitude Modulation and Frequency Modulation?
Addition of information to the carrier wave by varying the amplitude and frequency respectively
Ideal size of a dipole aerial?
Quarter or half the wavelength
A parabolic aerial transmits…
Directional signals (pencil beam)
A phase array aerial is made up of…
A series of small
What is Doppler shift?
An apparent change in frequency due to the relative movement between the transmitter and receiver.
Moving towards each other will increase frequency, moving away will reduce frequency.
