What is the maximum FM deviation for voice operation of a normal wideband channel on VHF and UHF?

Get ready for the FCC General Radiotelephone Operator License (GROL) exam. Study with flashcards and multiple choice questions, each with hints and detailed explanations. Prepare effectively for your licensing test!

Multiple Choice

What is the maximum FM deviation for voice operation of a normal wideband channel on VHF and UHF?

In FM, the maximum deviation is how far the carrier can swing above and below its center frequency due to the modulating signal. For VHF and UHF voice on a normal wideband channel, the standard limit is ±5 kHz. This keeps the signal within the 12.5 kHz channel spacing commonly used for land-mobile services, balancing audio quality with efficient use of spectrum and minimizing interference with adjacent channels. Deviations of 7.5 kHz or 10 kHz would require more spectrum and increase the risk of spills into neighboring channels, while 2.5 kHz is used for narrowband systems with tighter channel spacing but lower fidelity.

In FM, the maximum deviation is how far the carrier can swing above and below its center frequency due to the modulating signal. For VHF and UHF voice on a normal wideband channel, the standard limit is ±5 kHz. This keeps the signal within the 12.5 kHz channel spacing commonly used for land-mobile services, balancing audio quality with efficient use of spectrum and minimizing interference with adjacent channels. Deviations of 7.5 kHz or 10 kHz would require more spectrum and increase the risk of spills into neighboring channels, while 2.5 kHz is used for narrowband systems with tighter channel spacing but lower fidelity.

More practice questions