Which is true in a frequency modulated system ?

This question was previously asked in
VSSC (ISRO) Technician B (Electronic Mechanic) Previous Year Paper (Held on 25 Sept 2016)
View all ISRO Technician Papers >
  1. Variation of carrier amplitude does not affect quality of reception
  2. Amplitude of carrier is varied according to modulating signal
  3. The transmission does not require line of sight between transmitter and reciever
  4. Receiver uses diode detector

Answer (Detailed Solution Below)

Option 1 : Variation of carrier amplitude does not affect quality of reception
Free
DRDO Technician Fitter (Rank Booster): Mini Mock Test
5.1 K Users
60 Questions 60 Marks 45 Mins

Detailed Solution

Download Solution PDF

Frequency Modulation:

  • Frequency Modulation is a modulation in which the frequency of the carrier wave is altered according to the instantaneous amplitude of the modulating signal, keeping phase and amplitude constant.
  • So, the variation in carrier amplitude and carrier phase does not affect the signal in the receiving end.
  • Line of sight (LoS) is a type of propagation that can transmit and receive data only where transmit and receive stations are in view of each other without any sort of an obstacle between them. Eg: FM radio, microwave, and satellite transmission.
  • Frequency Modulation works on the Line of sight propagation.


Types of FM detection:

  • Slope detection
  • Phase-locked loop detection
  • Foster Seeley detection
  • Ratio detector
  • Quadrature detectors.
Latest ISRO Technician Updates

Last updated on May 28, 2025

-> ISRO Technician recruitment notification 2025 has been released. 

-> Candidates can apply for the ISRO recruitment 2025 for Technicians from June 2. 

-> A total of 64 vacancies are announced for the recruitment of Technician. 

-> The selection of the candidates is based on their performance in the Written Exam and Skill Test. 

-> Candidates who want a successful selection must refer to the ISRO Technician Previous Year Papers to increase their chances of selection for the Technician post. 

More Frequency Modulation Questions

Get Free Access Now
Hot Links: teen patti master king real teen patti teen patti wink teen patti gold old version