A diode detector is used to detect an amplitu | vedclass

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(C) Given:Modulation index,$m_a = 60\% = 0.6$Capacitance,$C = 250 	ext{ pF} = 250 	imes 10^{-12} 	ext{ F}$Resistance,$R = 100 	ext{ k}\Omega = 100

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$10.62 	ext{ kHz}$

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(C) Given:Modulation index,$m_a = 60\% = 0.6$Capacitance,$C = 250 	ext{ pF} = 250 	imes 10^{-12} 	ext{ F}$Resistance,$R = 100 	ext{ k}\Omega = 100 	imes 10^3 	ext{ }\Omega$The condition for proper detection of an amplitude-modulated signal without distortion is that the time constant $RC$ must be less than or equal to $\frac{1}{\omega_m m_a}$,where $\omega_m = 2\pi f_m$ is the angular frequency of the modulating signal.Thus,$RC \leq \frac{1}{2\pi f_m m_a}$.Rearranging for the maximum modulation frequency $f_m$:$f_m = \frac{1}{2\pi m_a RC}$Substituting the values:$f_m = \frac{1}{2 	imes 3.14 	imes 0.6 	imes (100 	imes 10^3) 	imes (250 	imes 10^{-12})}$$f_m = \frac{1}{2 	imes 3.14 	imes 0.6 	imes 2.5 	imes 10^{-5}}$$f_m = \frac{1}{9.42 	imes 10^{-5}} \approx 10615.7 	ext{ Hz} \approx 10.62 	ext{ kHz}$.

$A$ diode detector is used to detect an amplitude-modulated wave of $60\%$ modulation by using a capacitor of capacity $250 \text{ pF}$ in parallel with a load resistance of $100 \text{ k}\Omega$. Find the maximum modulation frequency which could be detected by it.

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