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Weather Alert for repeaters?


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So, the other day I was listening to the W2NJR ham radio network and heard an alert go out with an electronic statement "Thunder Storm Warning."


Basically, the W2NJR system uses the NOAA SAME code for the area to get weather alert and warnings. It then re-transmits the information following the coded signal, which is how the system knows what warning it is giving. This is legal on ham radio but what about GMRS? I am not planning on adding this feature to my repeater but if its legal I would think other systems could make use of it. The idea has just made me curious.

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Very good question.  I would like to know the legal part of this as well.  If for some reason it is NOT legal, then I need to take the EAS box off from my own GMRS system.


I use an older Sage ENDEC emergency alert system box, programmed with my call sign, to re-transmit weather warnings to my family's radios.  I have it programmed to ignore watches, tests, and other non-critical events, but it will forward any weather warnings for my area, as well as any local, state, or national level emergencies, and AMBER alerts.


It certainly does catch ones attention when an otherwise silent radio kicks on with the EAS tones, followed by "The National Weather Service in Hastings has issued..."


This is a fully legal use of the EAS, and it is accepted on CFR 47 Part 73, Part 74, part 76, part 90, and many other other radio services.  It is option on many radio services, but a mandatory requirement on others.  Of course it isn't required on Part 95, but is it allowed?  Very good question.

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Sounds good Jones. I believe a re-transmit would be unlawful, however, W2NJR simply uses its own voice to say "Thunder storm warning" or whatever major weather events are going on. I would think that it would be ok as long as it is in this format, but would likely require the repeater to transmit an ID.  I also believe that the "Broadcasting" clause may play a factor as well.

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Since weather warnings within the repeater's coverage areas are easily considered road condition alerts or emergency messages, they are authorized as one-way transmissions by 95.1731(b ). Synthesized voice doesn't appear to be an explicit violation of the rules. Since synthesized voice is still plain-language voice communications, attaching a synthesized-voice weather alert announcement system to an otherwise compliant GMRS radio wouldn't violate 95.339. Any violation I would imagine would be from the legality of that type of automatic control, but the purpose of the messages as emergency notification may override this.

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This is a very interesting topic.  I have disabled my EAS relay system until I get an answer.


As for the laws on use of EAS, it doesn't violate any of them.  It isn't a misuse of EAS tones, since these are real alerts, issued by authorities, broadcast for public consumption, and are simply being relayed as-is, without editing or modification.  I am not an authority, nor a PEP broadcaster, just an EAS participant; so I do not generate any of my own local alerts, just relay.


Obviously, if I were sending out EAS tones to tell the boys it's time for dinner, or sending zombie apocalypse messages, that would be a gross violation... but I do think weather warnings and AMBER alerts are important public information, and many times, the EAS relay message comes 5-20 minutes sooner than the same message from our cell phone providers.  Here in tornado alley, sooner is better.  We could get this same information using a NOAA weather alert radio, but that would be one more device for everyone to carry around.


Alerts from the National Weather Service are considered to be re-transmittable for public service.  All broadcast stations and cable systems are allowed to re-transmit NOAA weather radio audio, but many don't since it sounds bad on the air.... they have their own announcers/DJs read the weather.


As for identification: My call sign is embedded in the EAS tones as a participating relay, as required by the rules of EAS.  Immediately after an alert has been relayed, (and after ANY transmission has been over for 10 minutes) my controller has a synth voice that gives my station ID in English. (For those familiar, I run a CAT-400.)

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Strange this topic came up because I was wandering the same thing about a year ago and was never used. I have my Arcom programmed with DVR preprogrammed severe weather alert messages to seek shelter for incoming weather.. Through personal experience and Emergencies I would think they would turn a check as it is An emergency Alert (Grave Danger esp in the Tornado alley) As mentioned Rules are Rules, but I don’t think a DVR message is considered illegal broadcasting so long as you stay in Talk Guidlines parameters! Interesting!! I would think that allot and most alerts are long winded, and in most cases I believe over 2 minutes.. Either way, I would practice Good Judgement and flick the switch, it’s Not a live broadcast I do however have Garmin Rino radios with weather alert built right in, and came handy several times out and about. Especially in remote areas where cell coverage is NOT AVAILABLE!


Who Knows, May Save Lives, including AMBER ALERTS just an FYI, I am of Sound mind and use judgement when others FAIL TOO Someone has to, Good or Bad it’s called Responsible for Your own Actions.. Good Day!!

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... I would think that allot and most alerts are long winded, and in most cases I believe over 2 minutes..

The EAS rules state that watches and warnings activating EAS, including AMBER alerts, will be less than 2 minutes.  2 minutes is the default timeout of EAS relay boxes, so even if one doesn't hear the incoming EOM (end of message) tones, and gets "stuck", it will send its own EOM tones, and auto-reset after 120 seconds.


To the best of my knowledge, (I am a radio broadcast engineer) the only EAS message that is allowed to go over the 2 minute limit is a national emergency activation notification (EAN).  Those messages can be as long as the POTUS wishes them to be.


This has indeed been an issue in my state, as the highway patrol got very long winded and overly descriptive with the first few AMBER alerts they issued, and they were abruptly cut-off by all of the broadcast stations at 120 seconds.  They are now aware of this limitation, and use brevity, stating basic information one time, and telling listeners to go to the state website for more detailed information.


The average thunderstorm or tornado warning runs about 0:45 to 1:30 around here.  The weather radio will repeat these warnings every few minutes, but the EAS will only pass them one time, and log all the repeats of the same warning as dupes.  A new warning will have a different header code, sort of a message serial number, and will pass as a new alert.  That triple-blast of noise you hear as an EAS alert tone is actually FSK digital data, the header code, containing all of that automated message information.


For more information on EAS, see the Wiki:


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PB30X, I cant say I have ever heard a message go over 30 seconds where I am. I believe the W2NJR system will even reset if the message is over 45 as a default because it ties up repeaters across the state of NJ. I did laugh at the use of judgement comment lol. Seems like the world is lacking in common sense and logic. Quite scary when one thinks about it.


Jones, thanks for the added info, and I hope my post didn't scare you about using EAS on the repeater, I was more curious and I cant think of any repeaters or systems that use them locally for GMRS. Now that I learned the EAS alert tone is FSK data I am curious what info FLDigi would spit out when decoding it. Off I go to do more research!

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WRAK968 - FYI, in case you want to do some heavy reading, the EAS protocol is found in CFR47, Part 11.31




The digital header code is repeated 3 times.



See the text for what all of those variables mean - but it contains all of the information about the alert, including what it is, who sent it, who forwarded it, start time, expiration time and areas affected.

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  • 1 year later...

95.1731 Permissible GMRS uses.


The operator of a GMRS station may use that station for two-way plain language voice communications with other GMRS stations and with FRS units concerning personal or business activities.

(a) Emergency communications. Any GMRS channel may be used for emergency communications or for traveler assistance. Operators of GMRS stations must, at all times and on all channels, give priority to emergency communications

B: One-way communications. The operator of a GMRS station may use that station to transmit one-way communications:

(1) To call for help or transmit other emergency communications;

(2) To provide warnings of hazardous road conditions to travelers; or,

(3) To make brief test transmissions.

© Travelers assistance. The operator of a GMRS station may transmit communications necessary to assist a traveler to reach a destination or to receive necessary services.

(d) Digital data. GMRS hand-held portable units may transmit digital data containing location information, or requesting location information from one or more other GMRS or FRS units, or containing a brief text message to another specific GMRS or FRS unit.


If I understand this witch I may not. Weather alerts are ok because they are classified as emergency communications.

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Rebroadcast of NOAA Weather Radio is not considered as emergency communications except for the broadcast of watch and warning messages. These are very specific as warnings and alerts all start with a specific SAME burst. Alerts and warnings are also only in affect for a maximum of four hours or other period specified in the message. While it is fairly easy to detect the SAME burst to start he retransmission, it is not as easy to detect when the alert ends and that's the primary issue.

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