Question

What will be the image frequency of FM Radio receiver that is tuned to 98.6 MHz broadcast station?
A. 111.8 MHz
B. 108.8 MHz
C. 121.6 MHz
D. 132 MHz

Answer 1

Hint: In this solution, the image frequency is defined as the sum of the frequency of the station and twice the standard image frequency. The frequency is the signal that happens over a period of time with a particular width.

Complete Step by Step Answer:
Given:
The frequency of the station is${f_s} = 98.6\;{\rm{MHz}}$.
The equation to find the image frequency of the FM radio receiver that tuned to 98.6 is,
${F_{image}} = {f_s} + 2{f_{I.F}}$
Here, ${f_{I.F}}$ is the standard image frequency.
The standard value of the image frequency is \[11.5\;{\rm{MHz}}\]
Substitute the values in the above equation.
\[\begin{array}{l}
{F_{image}} = {f_s} + 2{f_{I.F}}\\
 = 98.6 + 2 \times 11.5\\
 = 98.6 + 23\\
 = 121.6\;{\rm{MHz}}
\end{array}\]
Therefore, \[121.6\;{\rm{MHz}}\] is the correct answer that is option (c).

Note:Be sure that the standard value of the frequency image is 11.5 and the 2 is multiplied to the standard value and not to the image frequency of the radio frequency of the tuned station.