According to Snopes there is no time limit for a national test.
Snopes is full of crap.......the EAS equipment (built to FCC regulations) only has a buffer large enough to store 55 seconds of speech at a time before another test must be initiated by the alert tones.
System capacity:Alert tones - 5 seconds (digitally encoded with the "type" of alert)
Message content - 55 seconds (unless transfered directly to NOAA's sutomated weather alert system, which provides the audio externally)
Cutoff tones - 5 seconds (resetting the equipment to a ready state)
There are four levels of "priority" that can be encoded into the alert tones:
1.) Emergency (immediate action)
2.) Warning (notification of an impending event)
3.) Watch (Notification of a "possible" event)
4.) Advisory (General event information)
A national emergency alert can refer the viewer/listener to a broadcast immediately following the test, which the feds can commandeer and air live in regular broadcast mode.
The equipment itself is
audio only, and will generate a text message (Chyron graphic file), which TV stations run as a crawl at the bottom or top of the screen. The equipment can be programmed to repeat the same message over and over for a long period of time (such as emergency weather alerts), but it is still limited to a finite quantity of information. There is NO video capability in the system.
It IS possible for the feds to use the NOAA weather system to provide an extended audio message to the equipment externally, however the code for a "National Alert" will not do that automatically, it must be placed into "manual" mode which can only be done by an operator at each and every station.
The "manual" mode is designed for emergency notifications of only local interest......"Amber Alerts" are an example of a use of the system for this purpose.
There is nothing particularly ominous about the EAS system at the individual broadcast station level.......it's simply a box in the equipment rack, measuring about three inches high, nineteen inches wide, and about (depending on manufacturer) eight inches deep. It typically contains three radio receivers.......one tuned to the "key" station (typically AM, depending on geographic area), a backup (typically FM, agan depending on area), and the third tuned to the NOAA automated weather radio transmissions (in the 110 MHz band). It also contains cheap-ass date/time clock, a microprocesser board, and less than one meg of RAM, with very simple firmware, which is designed to decode the alert tones and store the audio message, a Chyron generator, an audio amp, and a small speaker.
It is wired into the stations audio signal chain, so that when automatically activated it will "preempt", or override regular programming, and air what it is receiving from elsewhere, up to the limits of its design.
To broadcasters, they are basically a pain in the ass......primarily due to the fact that when the FCC wrote the specs, they failed to include a quartz clock, so the time has to constantly be reset to be accurate, because if the clock is wrong, the firmware is designed to interpret an alert whose time code is more than five minutes different than the built-in clock to be "expired", and will be ignored by the system. Each unit also contains a tiny thermal printer, which prints out an adding machine sized written notice of each alert, which is to be filed daily with the stations operating logs, per FCC regs. The printer is particularly annoying because here in "tornado alley", after a storny night, it is not unusual to come in in the morning to find fifteen feet of paper printouts hanging out of the device,
I know....WAY too much information, but I thought it important that the reader understand exactly what the system is......
and isn't.......
doc
