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More on Barnraisings!Sample Schedules and Schematics from Our Radio Barnraisings Below! Technical Information on Our Radio Stations!
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What Is a Barnraising?
Prometheus Barn Raising
How the SACReD Station will work
What's Missing?
Not shown is the uninterruptible power supply which is connected to critical components, like all the computers, the mixing console and the transmitter.
Also not shown is the grounding system for the audio components, all of which are connected by bare, braided copper wire to a grounding bus, and then connected to a good earth ground at the studio and transmitter site.
This chart shows only the main studio, and does not show a "pre-production" studio, for taping shows to be broadcast later.
How it Works
Audio will start either with one of the sources: the microphones, (a, b and c), the cd players (d &e) , the turntables (f&g), tape decks (I&j), cart machines (k&l), the phone patch (m), the computer (n), or whatever (h). It its good to have a few free spaces on your mixer or patchbay in so that people with their own audio sources (like minidisc players) can plug directly into the mixing board.
Audio sources plug into the mixing console (o). It comes out all mixed together at the appropriate levels, and goes to several outputs, including the headphones (p), recording deck (q), the audio processor, and the monitor amplifier (r ). Some stations use a "distribution amplifier" for this, but you can also use a regular home stereo amplifier, if you do not have too many places to go or too much distance to cover.
The monitor will power the studio speakers (s) and speakers in other rooms in the building, it can either have a radio receiver (t) built into the same unit as most home stereos do, or you can plug one into it in order to compare the sound coming out of the mixer to what is actually being heard by the listeners. With all receivers, it is important to remember that they should have a good antenna (v) in order to be able to pick up the station.
The audio processor's job is to make sure that the audio is not too loud or too soft before it goes to the transmitter. Then the signal goes into the soundcard of the studio side link computer (x). This computer is programmed in the Linux operating system, which is a free, open source system that is very stable and customizable because its code is open for anyone to see and change, while windows code is hidden, hard to customize and troubleshoot. Free custom software has been written to make sure the stream works and so that it automatically restarts itself if there are problems on the line. This computer encodes the audio digitally into 1s and 0s and sends it to the router (y) , which allows several computers to be connected to the same cable internet connection.
From the router, it goes into the cable modem (z) to a server (aa) on the internet. This is a company with a really big computer, so that anyone who wants to listen to you over the internet can hear a copy of the stream as it goes out.
Click on the image to view a jpeg of the entire schematic for SACReD's new station.
