Modulation: Why 455kHz is the IF Frequency

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A signal at the intermediate frequency (IF) of 455 kHz can cause significant interference with the intended AM signal, leading to poor reception and distortion. This interference occurs because a strong signal at this frequency can enter the IF amplifiers, disrupting the desired signal. While 455 kHz is a common IF frequency, it is not the only one used; different receiver designs may utilize various IF frequencies based on specific requirements. For instance, 10.7 MHz is often used for FM receivers. Understanding the implications of IF frequency selection is crucial for optimal receiver performance.
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why it is disaster if asignal exists in am at frequency of 455 khz , i mean asignal is at the IF frequency.


also why IF not greater or smaller than 455khz i need to know
thanks
 
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oufa said:
why it is disaster if asignal exists in am at frequency of 455 khz , i mean asignal is at the IF frequency.


also why IF not greater or smaller than 455khz i need to know
thanks

Your question is not clear. Please try again with more details and more context. Thanks.
 
why it is disaster if asignal exists in am at frequency of 455 khz , i mean asignal is at the IF frequency.
This should be obvious. If the signal is strong enough to enter the IF amplifiers then it will cause interference by coexisting with the signal you are trying to receive.

also why IF not greater or smaller than 455khz i need to know
thanks
455khz is not the only IF frequency. Other frequencies are used depending on the receiver design, desired receiving band, and number of conversions. For example, 10.7mhz is a common IF for the FM broadcast band receiver.
 
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