Starting High School Part 15 & Internet Station

There have been many similar requests over the years here at Part 15 (one just a week or so ago).  It's not an easy answer - much depends on your particular location (both installation and listeners).

First, I'd suggest searching this site for something like 'start radio station'.

But to give some scratching the surface answers, while Part 15 FM will give you the best sound, you're going to get a range of 100-200 feet to ordinary consumer radios, perhaps 600-800 feet to car radios (which are much more sensitive).  And that's line of sight, with nothing between your antenna and the receiving antenna.  It's possible to get anywhere between 1/4 mile to a mile of useable range with AM.

There are pros and cons to available Part 15 transmitters.  You can build one from a kit - it would be Part 15 compliant if it's built and installed properly - or you can buy an FCC certified prebuilt one, but even then, you need to ensure that it's installed correctly (you'll need to understand the Part 15 rules).

Streaming is a whole other can of worms.  There's plenty of free and paid for software available.  Some considerations - the speed of your internet or local area network (which, along with the bitrate you stream at, will determine the number of users you can support), what formats to stream (i.e., wma, mp3, aac, etc.) and perhaps most importantly, security (particularly if you're running your own server)- preventing malicious attacks on your computer and network.

Whether you're broadcasting or streaming, you also have to consider copyright licensing issues, which are different for both formats.  If you limit yourself to public domain material, or material for which you have permission to broadcast (such as independently produced music, talk shows, etc.), then you won't have to worry about that issue.

Hopefully that will get you started as to what to research.

My station (in Canada): For AM I use a ChezRadio Procaster, which is pretty much 'plug and play' in terms of installation, and FCC/Industry Canada certified.  I also use a Decade MS-100 for FM, but our rules are more lenient here (we're allowed 4 times the field strength, which translates to 4 times the range, which makes FM useable to some extent).

I use ZaraRadio for radio automation, Standalone OddCast to encode into MP3, and IceCast to distribute the stream to listeners.  Currently I only broadcast public domain music and Old Time Radio (copyright rules are different here in Canada - again, much more lenient) but prior to that we were licensed by SOCAN (Canada's only regulatory body, you have to deal with BMI, ASCAP and others separately in the U.S.).

Audio processing is done by VSTHost (software) with compression and conversion to mono - we stream and broadcast in mono, due in part to the type of material (vintage jazz, OTR) and also because broadcasting in FM mono gives you more range than FM stereo.

The computers are running Windows 2000 Advanced Server, partially because I have the licenses, but also because it is very stable, and runs very fast (unlike some of the bloatware that was released after it).  I've found that there is much more software available for the Microsoft platform than other platforms (such as Linux), but to each his own.

We stream MP3 at 40Kbps mono - my internet connection supported 5Mbps uploading, so we could theoretically handle 125 listeners.  In practice we had over 100 with no issues.  40Kbps was chosen by ear - 32Kbps (mono) was audibly worse, and I could detect little difference at, say 64Kbps (it was better, but not that much better).  40 gave me the biggest bang for the buck, so to speak.

And I think you'll find that like choosing the streaming speed for your particular station and content by trial and error, setting up that station will be much the same.  Trial and error.  That's why you need to get as much experiential information as possible before throwing yourself in, and doing what YOU need to do to satisfy your requirements.

Good luck.

Teaching radio can mean many different things, ranging from the technical side, board operation, various types of hosting and announcing, journalism and management, to name a few.

Since building a part 15 station is new to you, the teacher, perhaps you could share the project with students, put them to work gathering information and seeking advice, then you'll have a large pool of input to utilize in a laboratory stage when you all construct and test something.

It may not be perfect, but you and the class can learn from that and move into the upgrade stage.

Atisan Radio gave a good presentation on things to think about.

Two free streaming solutions I've used are Shoutcast and Icecast.

There are many free programs linked on this website, and a few more at

http://thealpb.com

We hope to hear from you again with physical details of the facility where the station will be located.

To engage the students, each student can build a very simple AM transmitter for a few dollars.

A 1 mHz crystal ocillator connected to a short wire can be received several feet away with a radio.  A simple microphone can be connected along with the battery to allow them to speak over the radio.

HERE IS A LINK to the instructions to build this project.  It includes the schematic and a nice explanation of how the radio signal carries the audio.

Carl, 

Thank you for the information!