FM Radio Circuits

  

 

Frequency modulation is used in telecommunications and signal processing, frequency modulation (FM) conveys information over a carrier wave by varying its instantaneous frequency.
This is in contrast with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant.
 
Frequency modulation can be regarded as phase modulation where the carrier phase modulation is the time integral of the FM modulating signal. FM is widely used for broadcasting of music and speech, and in two-way radio systems, in magnetic tape recording systems, and certain video transmission systems.
 
FM signals can be generated using either direct or indirect frequency modulation. Direct FM modulation can be achieved by directly feeding the message into the input of a VCO.
 
For indirect FM modulation, the message signal is integrated to generate a phase modulated signal. This is used to modulate a crystal controlled oscillator, and the result is passed through a frequency multiplier to give an FM signal. Is also used at intermediate frequencies by all analog VCR systems, including VHS, to record both the luminance (black and white) portions of the video signal. Commonly, the chrome component is recorded as a conventional AM signal, using the higher-frequency FM signal as bias. 
 
FM is the only feasible method of recording the luminance ("black and white") component of video to and retrieving video from Magnetic tape without extreme distortion, as video signals have a very large range of frequency components — from a few hertz to several megahertz, too wide for equalizers to work with due to electronic noise below -60 dB.
 
 

 

 

News

How to Process Audio for Streaming, Properly

Radio magazine How to Process Audio for Streaming, Properly Radio magazine The FM system uses emphasis (and thus pre-emphasis limiting). The 15 kHz audio bandwidth for FM means that a 32 kHz sample rate is adequate...

Feb 10, 2017

Pioneer Elite SX-S30 Slim Stereo Network Receiver Preview

Pioneer Elite SX-S30 Slim Stereo Network Receiver Preview Audioholics (press release) (registration) (blog) Expanding its catalog of precision-engineered two-channel offerings, Pioneer Home Entertainment announced its new...

Feb 7, 2017

Day: February 13, 2017

Hackaday Day: February 13, 2017 Hackaday If you've ever cast your eye towards the rooftops, you'll be familiar with the Yagi antenna. A dipole radiator with a reflector and a series of passive director elements...

Feb 13, 2017

HealthMax Group, Inc. interview on KCAA radio Morning Show

HealthMax Group, Inc. interview on KCAA radio Morning Show SYS-CON Media (press release) Recently, the station upgraded all broadband connections and added new audio delivery systems to the transmitters, specifically MP4...

Feb 22, 2017

Kits Solve a Multitude of Problems

Kits Solve a Multitude of Problems Radio World The LeaningTech DSP and PLL Digital Stereo FM Radio Receiver Module with serial control costs just $14.32 on Amazon and features an LCD display with very low power...

Nov 22, 2016

T-Mobile Galaxy S7 and S7 Edge gained FM radio in the latest update

Android Authority (blog) T-Mobile Galaxy S7 and S7 Edge gained FM radio in the latest update Android Authority (blog) One such system improvement that T-Mobile users discovered is the activation of the radio...

May 5, 2016

RadioNet Looks Back at Internet Radio

RadioNet Looks Back at Internet Radio Radio World ... conventional AM/ FM receivers . (RadioNet's first such unit was a US$99 purple plastic receiver module that, although its audio was tinny and thin-sounding,...

Jun 13, 2016

Norway becomes world's first country to switch off FM radio

The Independent Norway becomes world's first country to switch off FM radio The Independent “Additionally, its FM radio infrastructure was coming to the end of its life, so they would've needed to either...

Jan 11, 2017

Is DAB the new FM?

Electronics EETimes (registration) Is DAB the new FM ? Electronics EETimes (registration) Are the times gone when AM and FM radio receivers dominated the center stack in the cars? The latest figures from the...

Nov 3, 2016

5 Things I Love About The LG G5

Android Police 5 Things I Love About The LG G5 Android Police Another legacy feature that Samsung and HTC have basically abandoned on newer devices? Yep: FM radio is a legitimately useful add-on, and one that...

Apr 29, 2016

Units & Modules