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178. A phase modulator has a sensitivity of kp = 3 radians per volt. How much frequency deviation does it produces with a sine-wave input of 2V peak at a frequency of 1 kHz? amplifier has a carrier output power Pc of 100W and an efficiency of 70%. Calculate the supply power and the transistor power dissipation with 100% modulation. Carson’s rule, calculate the bandwidth of the signal. the bandwidth of the signal. Calculate the approximate signal-to-noise ratio at the detector output. 182. A crytal oscillator is accurate within 0.0005%. How far off frequency could be at 27 MHz? 183. A transmitter has a carrier power output of 10W at an efficiency of 70%. How much power must be supplied by the modulating amplifier for 100% modulation? 184. A transmitter operates from a 12V supply, with a collector current of 2A. The modulation transformer has a turns ratio of 4:1. What is the load impedance seen by the audio amplifier? 185. A collector modulated class C amplifier has a carrier output power Pc of 100W and an efficiency of 70%. Calculate the supply power and the transistor power dissipation with 100% modulation. 186. An AM transmitter is required to produce 10W of carrier power when operating from a 15V supply. What is the required load impedance as seen from the collector?
187. A portable radio transmitter has to operate transmitter has to operate at temperature from -5 to 35 degrees C. If its signal is derived from a crystal oscillator with a temperature coefficient of +1 ppm per degree Celsius and it transmits at exactly 146 MHz at 20 degrees C, find the transmitting frequency at the upper temperature limit. 188. A phase-locked loop has a VCO with a free-running frequency of 12 MHz. As the frequency of the reference input is gradually raised from zero, the loop locks at 10 MHz and comes out again at 16 MHz. Find the capture range and lock range.