A-005-05: FM deviation, modulation index, deviation ratio, deviation meter
In an FM phone signal having a maximum frequency deviation of 3000 Hz either side of the carrier frequency, what is the modulation index, when the modulating frequency is 1000 Hz?
What is the modulation index of an FM phone transmitter producing an instantaneous carrier deviation of 6 kHz when modulated with a 2 kHz modulating frequency?
What is the deviation ratio of an FM phone signal having a maximum frequency swing of plus or minus 5 kHz and accepting a maximum modulation rate of 3 kHz?
What is the deviation ratio of an FM phone signal having a maximum frequency swing of plus or minus 7.5 kHz and accepting a maximum modulation rate of 3.5 kHz?
When the transmitter is not modulated, or the amplitude of the modulating signal is zero, the frequency of the carrier is called its:
In a FM transmitter system, the number of cycles of deviation from the centre frequency is determined solely by the:
amplitude of the modulating frequency
frequency of the modulating frequency
amplitude and the frequency of the modulating frequency
modulating frequency and the amplitude of the centre frequency
Any FM wave with single-tone modulation has:
an infinite number of sideband frequencies
two sideband frequencies
four sideband frequencies
one sideband frequency
The deviation meter works on the principle of:
a carrier null and multiplying the modulation frequency by the modulation index
detecting the frequencies in the sidebands
the amplitude of power in the sidebands
a carrier peak and dividing by the modulation index
When using a deviation meter, it is important to know:
modulating frequency and the modulation index
pass-band of the IF filter
What is the total bandwidth of an FM-phone transmission having a 5-kHz deviation and a 3-kHz modulating frequency?
What is the frequency deviation for a 12.21-MHz reactance-modulated oscillator in a 5-kHz deviation, 146.52-MHz FM-phone transmitter?
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