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I am surprised no one has tried to home brew an EAS box using an old PC running Linux OS with a few sound cards and audio switcher.
I am surprised no one has tried to home brew an EAS box using an old PC running Linux OS with a few sound cards and audio switcher.
seems a simple program can be written for Linux to generate a EAS log (either print or electronic) and decode/encode EAS alerts and control an audio switch to switch the EAS in line and pass the EAS alerts to the main program.
seems to me this can be easily done with off the shelf hardware and there are many genius’ on here who are more than capable of writing a small program.
Total posts : 45366Putting such hardware together isnt the issue. The issue will be obtaining the software that will decode and encode properly.
Total posts : 45366EAS is soon to be a system of the past with the new CAP digital alert system to be in effect in the next several months. There has already been an extension of the deadline for conversion, so who knows how long the change over will really take. Plus the new CAP system is supposed to allow local authorities coded access directly to the radio station alert system equipment. So, now it will not only take generation and decoding of the “quack” sound, but also the CAP codes used in the system for your region and local area.
In short, designing and building a seat of the pants EAS-CAP endec might be a tall order without the proprietary knowledge and codes.
For reference purposes, here is the latest from “COMMLAWCENTER.COM”:
“Big CAP Extension Win at the FCC for Broadcasters/Cable Operators
Posted November 23, 2010
By Paul A. Cicelski
As Scott Flick reported in a previous post, our firm filed a Petition on behalf of an unlikely coalition of broadcast and cable associations and their allies, including 46 of the state broadcasters associations, the National Association of Broadcasters, the National Cable and Telecommunications Association, the Society of Broadcast Engineers, the American Cable Association, the Association for Maximum Service Television, National Public Radio, the Association of Public Television Stations, and the Public Broadcasting Service. The parties joined forces to ask the FCC to extend the deadline for all EAS Participants to acquire and install the equipment necessary to use the Common Alerting Protocol (CAP) standard for Emergency Alert System alerts. The unified effort paid off, as today the FCC released an Order waiving Part 11.56 of its Rules and extending the CAP deadline from March 29, 2011 to September 30, 2011.
Last September 30, FEMA announced the adoption of the CAP v1.2 standard, which triggered a 180-day deadline for implementation. In a post found here, I described CAP and what the CAP compliance deadline requires of EAS Participants.
The extension means that the estimated 25,000 to 30,000 EAS Participants now have more time to acquire the new and sophisticated equipment they need to become CAP-compliant, while giving FEMA more time to certify CAP-compliant EAS equipment. The six-month delay will also allow equipment manufacturers to test their CAP products and to make any changes needed to meet the certification requirements. This process, in turn, will give EAS Participants the certainty they need to make better informed decisions regarding what equipment they should obtain and install to ensure compliance with CAP. Finally, the extension will give all parties, including noncommercial broadcasters, smaller cable systems, and rural broadcasters more time to budget for the purchase of new equipment.
The FCC acknowledged that if it failed to extend the 180-day deadline, it could “lead to an unduly rushed, expensive, and likely incomplete process.”
The Order also leaves open the possibility of extending the CAP deadline beyond September 30, 2011. This is because the FCC will soon be conducting a rulemaking proceeding to incorporate CAP into its Part 11 Rules, and at this point it is unclear what specific Part 11 rule changes will be made as a result of the new CAP standard. According to the FCC, it plans to complete that rulemaking prior to September 30, 2011, but will ask for comments on “whether the extension for CAP acceptance by EAS Participants granted in this waiver order is sufficient, and reserves the right to further extend the date for CAP reception in any new rule we may adopt.” Given that the outcome of the rulemaking proceeding will likely result in a number of significant revisions to the FCC’s EAS Rules, another extension of the deadline is certainly plausible in order to give parties enough time to come into compliance with the new rules.
In other words, stay on alert, as we will definitely be hearing much more about CAP in the near future.” – COMMLAWCENTER.COM (2010)
Total posts : 45366Once things are in place with the new CAP system, assuming the Part 15 operator can obtain the required equipment, homemade or otherwise, perhaps a Part 15 station can apply for formal membership with the agency which manages the CAP. If possible, that would provide the necessary code and instruction for participation.
Total posts : 45366how do you think trunking police scanners came about. it was from out in the field hobbyists decoding and analyzing the data and writing scanner controller programs.
EAS/CAP is no different. Hard at first as far as obtaining data yes, but once the data is gathered there can be a program written that will run on a p1 desktop run dsl linux and some sound cards.
it will take a collaboration of several hobbyists to get it done but come on we are a resourceful bunch here. lol
Total posts : 45366Emergency Services post-9/11 are all under the direction of the Department of Homeland Security (DHS) with several Federal and State agencies doing the foot work. Statewide and local EAS network structure won’t change with CAP. In fact, it will make the LP-1 stations more responsible than ever for dissemination of tests and alerts.
Even if it were possible, applying for formal membership in the EAS network would put the Part 15 station under the jurisdiction of the FCC and State Emergency Management. Federal law and the current rules for a declaration of an emergency puts membership in EAS outside the legal parameters of Part 15 operationally (hobby radio). In other words, the feds can’t make an unlicensed radio entity do the required weekly or monthly tests, keep records of the tests or demand that Part 15 stations be required to send an alert. There is no legal authority to do such a thing.
Under a Presidential Declaration, as an example, Part 15 radio stations would be REQUIRED to go off the air. Many licensed stations are now required to do the same.
My emergency communications training, over the years since 2001, indicates DHS does NOT want everybody included in the system regardless of whether they have a heartfelt wish to participate. To be a part of the system post-declaration requires training and registration with the government. I would recommend a visit to the office of the local emergency manager in your area to learn the specifics, if you are interested. Each county EM agency is required to have an emergency plan. Find out where they need help and fill the need. Don’t be disappointed when they tell you your 100 milliwatt power house is not part of the plan.
If you happen to live in the middle of “no-where” and there are no radio stations, TV stations, cable TV, WiFi, internet, telephone, Amateur Radio, CB, Public-Address System or tin cans and string, then your Part 15 stations may qualify for membership in the EAS network. Then, be ready to fill out a lot of paper work and go back to school. Been there, done that. I have been a part of the local EM communications network with licensed broadcasting and amateur radio (ARES-RACES). Good luck.
Total posts : 45366Just a thought: Suppose you get the equipment together and it contains the necessary codes (which are constantly changing). You decide to run an on-air test of your system, the test is picked up (received/decoded) by a licensed station’s equipment and logged. What kind of confusion do you think this will create? What would be the reaction of the FCC to this situation? What kind of credibility issues will this raise with the local emergency management folks and local broadcasters?
My opinion: With the seriousness the FCC is giving to EAS compliance presently, this situation would bring the full weight of the Commission down on the Part 15 operator. This would not be an NOUO. It would be a violation of federal law with a visit by FCC inspectors and federal marshals. I am all for technical innovation, but not for the sake of showing off. This might not be the venue for this discussion. I’m just sayin….
Total posts : 45366I seriously doubt the government would come after you for re-transmitting EAS. In the end, as long as you are part15 compliant, you are legally considered background noise which can be ignored.
As far as supporting EAS on your part15 rig, this was my plan (if I ever get my station back on the air). I picked up a Midland weather radio and was going to use an Arduino to read the status from it. It has an LED that indicates if it has picked up an alert. I could use that as an input into the Arduino and have it change the audio source with a relay to come from the weather radio. Then, after about 5 minutes or so, it could clear the alert from the weather radio and change the audio source back to the playout system. You could certainly get fancy and have a serial interface to the playout PC so it could be aware of the switch, but that seems like overkill. You could also scale this back to just use an ATTiny13 or other small microcontroller.
This is the radio I intend to use for this:
http://www.midlandradio.com/Desktops-Weather.OCS/WR-100
Total posts : 45366Also, it’s worth noting that CAP is supposed to be backwards compatible with EAS as far as the protocol EAS uses (SAME – Specific Area Message Encoding). In theory this may mean existing weather radios that support SAME decoding should also support CAP.
The EAS SAME protocol is documented quite well: http://en.wikipedia.org/wiki/Specific_Area_Message_Encoding
Someone now has a website that will encode and decode EAS/SAME messages to/from audio:
http://www.drewkirkman.com/projects/noaa-same/Looks like someone has already made a SAME encoder based on an ATTiny45:
http://www.circuitcellar.com/avr2006/winners/AT3249.htmI used to know of a kit for decoding SAME messages for use on Ham radio repeaters, but I can’t seem to find it. I’m sure it’s out there still.
Total posts : 45366i was wondering if a Weather Radio equipped with SAME and and audio relay would do just as good. i was just thinking of the software end to add logging capabilities to the system.
just something simple. decode, log date/time and pass emergency or test message. no actually encoder for another station to pickup and relay.
i was thinking of this because a lot of us have part 15 networks and internet streams in addition to single site transmitters.
Total posts : 45366What I do is I have a scanner plugged into my board tuned to the strongest NOAA station. In event of a weather emergency I will listen to another scanner (I have 3) to listen for the tones or important information. The second those tones start to sound All it takes is a flip of a switch on my board to interrupt programming and put the message on.
It might not be automatic, but it does work.
Total posts : 45366I must be lazy but here’s what I’m doin’.
I use Weather Watcher to import wx data into ZaraRadio. Weather Watcher provides an audio alert whenever NOAA puts out a warning.
So, I made my own audio clip that is played by Weather Watcher and it simply tells listeners that a Special Alert has been issued by NOAA Weather and they should listen to their Weather Radio assuming they have one. Otherwise tune to another local radio or TV station for info.
The audio clip plays louder than the Zara program so the audio compressor adjusts and puts it up front.
Total posts : 45366If I hear thunder, see lightning or the trees bend over, I shut off, because an electrical surge can cause major damage.
If there’s an earthquake I just keep operating, because by the time Windows Operating System shuts down the quake is past history by 1-minute and it’s time to start the long re-boot.
Thing is my main concern goes to the computer equipment and online audience, while the part 15 listener is me, and I already don’t know what’s going on, so there’s no reason alerting myself any further.
Total posts : 45366I have run this setup on my ham repeaters and part15 stations for about 30 years now. I have a weather alert reciever modified with a timer and keying interface that listens for the old 1050hz tone and autoplays for 2.5 minutes and resets. I am working on a new SAME receiver to update it for selected alerts.
Total posts : 45366Amateur Radio Emergency Service —
I think this is a better option for Part 15’er types who want to participate in emergency services. The go packs here on San Juan Island allow access to the internet by using a network of repeaters to reach out of the disaster area. This kind of response allows all kinds of organizations, including local Sheriff and Fire/Rescue units to stay in touch with the outside, in this case off-island, resources and mobilization, because it’s possible that their radio communications online gear could get toasted. Such participation is actually encouraged by the NTS with Homeland Security.
I haven’t taken the tests yet, but that’s where I’m headed with emergency communications. THe ARRL has a number of publications on various aspects of the ARES and NTS. It’s actually fascinating stuff. NHS wants this sort of help, but mainly because they figure hams who take the time to get licensed and qualified will be more knowledgeable and trustworthy, at least enough to recognize when they’re needed as opposed to getting in the way.
EAS/CAP has plenty of coverage … It’s nice to want to help, but I don’t think a Part 15 AM or FM BCB station is the way to go in any scenario I can think of. I’d probably make an on-air plea to turn on legitimate EAS/CAP participating stations and get the heck off the air.
However, broadcasting updated information about local temporary power outages, weather alerts, road conditions during winter storms, ground fog, stuff like that, is a good thing …. I do it all the time. Sometimes I even broadcast info about excessive deer sightings on portions of the roadways (two Augusts ago, we were having 3 road kills per day for a couple of weeks on the island). As a taxi driver, I’m often on point with road conditions. I was out one night wishing I had a resource to tell me how bad the conditions were … when it dawned on me … I AM that resource, because I’m the first (or one of the first) driver to encounter it!
So how would I set up a system where I could get a 2-meter rig to switch my Part 15 station to receive broadcasts from a hand-held or mobile rig in my taxi when in range. It could save someone from getting themselves into a driving situation they can’t handle.
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