Instruction manual

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Narrow Band The selectivity of the entire system is limited to only enough frequencies to pass
voice or low frequency data. A normal FM receiver would have a bandwidth large
enough to pass music and high frequency data transmissions.
FM Radio Receiver The letters “FM” stand for Frequency Modulation . The other popular forms of
modulation are
AM (Amplitude Modulation) and PM (Phase Modulation).
Frequency modulation means the data or voice changes the frequency of the
radio wave.
Amplitude ModulationFrequency Modulation
Figure 4
Figure 3
Narrow Band
Wide
Bandwidth
3kHz 200kHz
2 Meter Band If the speed of a wave (meters per second) is divided by the number of waves that
pass a given point (cycles per second), the seconds cancel and you obtain the
wavelength (λ = meters per cycle). The speed of radio waves is approximately
300,000,000 meters per second. If the frequency is 150MHz, the wavelength
becomes 300,000,000/150,000,000 or 2 meters.
6 Meter Band To find the frequency in MHz, divide the speed in millions of meters per second
by the wavelength in meters. A 6 meter wave has a frequency of 300/6 or 50MHz.
Actual bands are: 2 Meter covers 144MHz to 148MHz.
6 Meter covers 50MHz to 54MHz.
All licensees, except Novices, are allowed to use these bands.
50MHz150MHz
Figure 5
2 Meters
6 Meters