- An AM receiver is tuned to broadcast station at 600 kHz.
Calculate the image rejection in dB, assuming that the input filter
consist of one tuned circuit with a Q of 40?
- An SSB system transmit a peak envelope power of 100 W into a 75
ohms load. The carrier signal is modulated by two tones, with
frequencies 2 kHz and 3 kHz with equal magnitude and only the lower
sideband is transmitted with a suppressed carrier. Determine the
average power into the load?
- In the SSB, determine the maximum suppression of the unwanted
sideband if the deviation from a perfect 90 phase shift is 5”?
- An AM transmitter has an output power of 100 W at no modulation
with efficiency of 60 %. What will be the output power with 97 %
- Given an audio power of 500 W which will modulated an RF
amplifier to 50 % modulate an RF amplifier to 50 % modulation. Find
the DC power input?
- A CB transmitter supplies a total power of 120 W to an aerial.
Suppose the carrier is amplitude modulated to a depth of 80 %, how
much power is wasted by the carrier signal?
- Determine the modulation index of the signal given the
following parameters: Emax = 10 Vp, Em= 4 Vp.
- A DSB-SC system must suppress the carrier by 50 dB for its
original value of 10 W. To what value must the carrier be
- A transistor has a power dissipation rating of 30 W. Assuming
that the transistor is the only element that dissipates power in a
circuit, calculate the power an amplifier, using this transistor,
could deliver the load if it operates as Class-A wit an efficiency
of 30 %?
- An AM signal supplies 150 W of carrier power when it is
modulated by a single sine wave to a depth of 70 %. Suppose the
total transmitted power increases by 10 % when another sine wave
simultaneously amplitude modulates the carrier, determine the
modulation index of the second sine wave?