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Signal Flow, Phase, and Amplification

Audio Signal Flow Here's the basic signal flow explanation of a (Mackie) mixer.  Use this mainly to review.
Audio Mixer Here's a guided tour of a larger audio mixer, generic, in six steps.
Transistor video Here's a video demonstrating what a transistor is and how it uses a very weak signal to control or modulate a very strong one, thereby producing amplification
Simple Radio Station Here's how to set up a simple home radio station.    Look how the main pieces are tied together.

Transducers

We use a variety of devices to convert energy from one state to another.  These devices are known as transducers.  They are explained here.    
The most common upstream transducer is a microphone.  Microphones are sensitive to shock waves in air.  When they sense a shock wave, they produce a pulse of electrical energy.  The stream of electricity, pulsing in a way that corresponds to the shock waves, is known as the signal flow.  
Don't remember how sound waves are produced and travel?  Look here for a - B/W - video!
Microphone graphics A dynamic mike, a condenser mike, and a ribbon mike.   An electret mike is a widely-used form of the condenser.  Also a loudspeaker (the reverse of a dynamic mike!)
Understanding microphone specifications Here are four short videos from Shure, a maker of popurlar professional microphones.  The link will take you to Part One.  Parts 2-4 will be revealed in the right panel.of "up next" videos.
Brief Guide to Microphones From Audio-Technica, this site offers a clear foundation, including a discussion of signal flow.
Microphone techniques A pdf tutorial on how to use microphones
Microphones - Coutant This site will introduce you to the various types of microphones used in broadcasting and in recording studios.  Remember, they're upstream transducers! It is a small sample (only 20 or so), and includes a few of the older models of RCA ribbon microphones such as the 44B and 77DX. Many of these classics still exist, and continue to provide superb audio quality. You can even take a tour of the Neumann factory. Pay particular attention to mike types, frequency response, and polar patterns. This information is provided with each microphone and also, generically, as a link ("Types of Elements") at the very bottom of the first page ("RCA Type 44-BX") of the microphone tour.  Direct links are here.
Microphones for TV Notice here the photo of a parabolic microphone, which actually is a normal dynamic (cardioid) microphone on a parabolic reflector mount.
Phonograph stylus The diamond-tipped "needle" bounces in the record's groove. The needle's connected to a wire coil in the cartridge, placed near a permanent magnet. Each time the needle moves, current flows. The very low output (signal strength) requires an amplifier to be near the tone arm, usually under the turntable base.  This funky video shows an optical "record," too.
Magnetic record head The audio tape is a plastic ribbon many feet in length. Standard reel-to-reel tape speed is 7-1/2 inches per second. The audio recording on the tape exists as many, many little areas of magnetism. As the tape is drawn past the head, each area of magnetism creates electrical flow in the tape head. These signal impulses are sent directly to an amplifier. 
Computer disk drive Uses a tiny, tiny magnetic record/playback head similar to what's in a tape recorder. The disk itself is coated with very fine metallic dust. Because the disk spins, the record/playback head can be made to move along an extremely thin spiral track from the center of the disk to the outermost rim. As the head passes over spots on the track that are magnetized, electrical impulses are created in the head. These are sent to an amplifier in the disk drive.  
Loudspeaker A loudspeaker, or simply speaker, is an electromechanical transducer which converts an electrical signal into sound.  
Microphones Pretty good explanations, with home-made visual aids.

Audio Mixing and Processing Products

Arrakis Arrakis provides both air/production mixers ("boards") and studio automation software.  The Digilink-Free is a free download which you can study or use.  Click on the dropdown menu for "Automation."  Then  "Digi-Link Extreme," and then explore the features.  A video is available on this page..  Then return to the main page and click on the dropdown menu for "Consoles."   Explore these mixers ... especially the REV-12P.  Furniture is obvious.
Enco's DAD Enco's Digital Audio Delivery products are displayed on this page.  You'll find a demo by clicking on the graphic at "DAD."
Signal Processing Dynamic Processing comes under the categories of Compression, Limiting, Expansion & Gating.  "dbx" makes the signal processor we use in the TV studio
EAS A description of the system in Alaska is here.
Telephone interface Normally called "a Gentner," the interface controls incoming phone calls and allows you to put them into the audio board.  
Eventide Eventide invented the digital talk show delay for radio.  The "manual" (pdf) at the page bottom is user-friendly.  The device in use is here.
Abekas AirCleaner The simple machine that puts a profanity delay on audio or both audio and video.  Look at the brochure on the Abekas site or at this video.  Notice also the instant replay server system that preceds the AirCleaner. 
WavePad This free audio editor is simple and powerful 
Audacity How to use Audacity for simple podcasts - Part 1, Part 2 and Part 3
Adobe Audition How to use Audition for audio effects - Part 1, Part 2 and Part 3

Misc. (not required)

Radio station Tour a radio station with Corey Deitz
WFPG tour The studios are located at Northfield and Venice Park, NJ and the transmitters are located in the well suited meadows of Atlantic City.  Studio and transmitters. Actually, this site is large and includes much technology of the 1960's and 1970's -- all analog.
Faraday Learn about Faraday, Maxwell, Hertz and Marconi at John Henkins' SparkMuseum.  Good explanations plus clear photos of early radio technology.   On this page you'll find links to key documents related to the emergence of broadcast technology.  Start with Faraday.
Telegraphy Learn about telegraphy, the Morse Code (binary), and the transatlantic cable.

Tesla

Nikoli Tesla invented alternating current and held many early radio patents.  This site from PBS offers a biography, a profile of five inventions (including "radio"), a tour of his Niagra power station, and an explanation of the fundamentals of electricity.
Marconi

You can learn about Marconi, read Titanic telegrams, and see footage from Marconi's life here.

In-band/on-channel

From Wikipedia
BBC studios Roger Beckwith's extensive site
 

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