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A diode detector has a load of 1kΩ shunted by a 10000 pF capacitor. The diode has a forward resistance of 1Ω. The maximum permissible depth of modulation, so as to avoid diagonal clipping, with modulating signal frequency of 10kHz will be—
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- 0.847
- 0.628
- 0.734
- None of these
- 0.847
Correct Option: A
We know that
RC ≤ | √ | ||
ωm | μ2 |
given that R = 1 kΩ = 1000Ω
C = 10000 pf = 10–8 f
ωm = 2π fm = 2π × 10 × 103 radian/sec
μ =? (neglecting diode forward resistance i.e.1Ω)
1000 × 10−8 ≤ | √ | ||
2π × 10 ×103 | μ2 |
or
0.628 ≤ | √ | |
μ2 |
or
0.394 ≤ | |
μ2 |
or
0.394 μ2 ≤ 1 − μ2
or
1.394 μ2 ≤ 1
or
μ2 ≤ | |
1.394 |
or
μ ≤ 0.8469
or
μmax ≤ 0.847
Hence alternative (A) is the correct choice.