An audio signal of frequency 500 Hz and voltage 2.4 V is frequency modulated with a carrier wave, and a frequency deviation of 4.8 kHz occurs.If the audio voltage is increased to 5 V, the frequency deviation (in kHz) will be :
10
9.6
4.8
5
As we have learned
Value of frequency deviation (d) -
- wherein
modulating amplitude
We know for frequency modulation , frequency devaition
Here 4.8 KHz = K(2.4 V)
K = 2 KHz / V
Now the audio voltage is incresed to 5V since the deviation is proportional to audio voltage , it shall also increase accordingly
= (2 KHz / V) * 5V
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