Discussion
Indicate the false statement in the case of Armstrong modulation system.
I. The system is basically phase and frequency modulation.
II. The system is also amplitude modulation.
III. Frequency multiplication must be used.
IV. Equalization is unnecessary.
Answer: C
The key takes statements I and III as correct, so option (C) is right, which makes statements II and IV the false ones. The Armstrong system generates frequency modulation indirectly: a crystal-controlled carrier is phase modulated by a signal that has been integrated, which is the phase and frequency modulation of statement I, and the small frequency deviation is then raised by frequency multiplication, statement III. Statement II is false, since the system is not amplitude modulation, although an amplitude component is removed with a limiter. Statement IV is false, because the integrator in the modulating path, a form of equalisation, is necessary. Options (A), (B) and (D) include a false statement as a correct one.
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development