Question
Download Solution PDFIn a typical AM receiver circuit, the oscillator frequency is
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFThe most typical AM receiver circuit is the superheterodyne (SHD) receiver.
In the receiver circuit, the local oscillator frequency is:
fLO = fRF + fIF
Where,
fRF = radio-frequency or signal frequency.
fIF = Intermediate frequency.
Since, for AM broadcast, the typical intermediate frequency is 455 kHz.
So, fLO = fRF + 455
This is showing that fLO must be higher than the signal frequency by 455 kHz.
Important Parameters for AM and FM signals are:
Parameters |
AM |
FM |
Carrier frequency |
540 – 1700 kHz |
88.1 – 107.9 MHZ |
Carrier spacing |
10 KHZ |
200 kHz |
Intermediate frequency |
455 kHz |
10.7 kHz |
IF Bandwidth |
6 – 10 kHz |
200 – 250 kHz |
Audio Bandwidth |
3 – 5 kHz |
15 KHZ |
Last updated on Jul 2, 2025
-> ESE Mains 2025 exam date has been released. As per the schedule, UPSC IES Mains exam 2025 will be conducted on August 10.
-> UPSC ESE result 2025 has been released. Candidates can download the ESE prelims result PDF from here.
-> UPSC ESE admit card 2025 for the prelims exam has been released.
-> The UPSC IES Prelims 2025 will be held on 8th June 2025.
-> The selection process includes a Prelims and a Mains Examination, followed by a Personality Test/Interview.
-> Candidates should attempt the UPSC IES mock tests to increase their efficiency. The UPSC IES previous year papers can be downloaded here.