The Answer

The FCC originally thought that it would save some money for LPFMs by allowing them to buy "decoder only" EAS machines. But when manufacturers released these, they charged basically the same price or a bit less for them, and the FCC required stations to have them anyway! There was a period where you were allowed to apply for a waiver because of economic hardship, but that is now over and all LPFMs are required to have an EAS system.

Again, there are just decoders, but they are not a lot cheaper. Broadcast Richardson -- http://www.rell.com -- and http://bswusa.com have them -- as does engineer and ally Michael Brown -- http://www.brownbroadcast.com.

With an EAS, you basically need to accomplish four functions --

 1) receiving of the alerts, often on a normal FM or TV receiver from the central station. You will be assigned two channels to monitor for the alerts.

 2) The decoder unit, which hears those bleeps on the reciever and goes into action!

3) An automatic relay that seizes control of your audio from the station, cutting it off and putting in place the emergency message.

4) A printer, which you use to record the alerts you receive and document that your EAS system is working properly.

Buying these things is complicated because some are cheaper than others, but they leave out certain parts of the process. For instance, you can buy a stripped down model and provide your own FM receiver and printer and relay switch, and save considerable money. However, you would then have to figure out how to patch all that stuff together. Or, you could buy it all in one box, set it and watch it work.