GMRS Radio (SHTF text messaging?) and Faraday Cages (EMP protection?)

Diversifying, Reinforcing, and Protecting Your Comms

(Am writing this to contain info that I think is genuinely helpful to the Patriot community, so am hoping it will get pinned by the mods.)

I shouldn't need to belabor the point that the Internet has gotten progressively more and more hostile for Patriots to maintain a presence - the site Gab.com is a Poster Child for what happens to those that take a stance for free speech on the Internet. Methinks it prudent to presume that things will only get worse.

Well, I want to try and take some concrete measures to do something. I may have some even worse case scenarios in mind of where this could go than others, just bear with me and then decide.

I have two basic topics:

• GMRS Radio (enhancing it with text messaging and then DNS server list discovery)
• Homemade Faraday Cages for protecting electronic gear (from EMP)

Let's tackle General Mobile Radio Service (GMRS) first:

The FCC has set aside frequencies for family use, emergency related use (think search and rescue kinds of things, disasters), and other uses such as running events. It's line of sight communication and the the FCC allows up to 50 watt transmission, which is not too shabby. A handheld radio might be good for 1 to 3 miles and the beefier transmitters up to 10 to 30 miles - but all dependent on terrain and conditions, of course.

Obviously this is not the kind of band that is good for bouncing off the ionosphere and communicating very long distances. However, there are GMRS repeaters and those are fairly widespread across the continental 48 states. There are relatively inexpensive GMRS handheld radios that are capable of interacting with GMRS repeaters, and once you get onto a repeater, well, given how these are sometimes networked, you can conceivably talk with someone off in another state entirely - more about networked GMRS repeaters later.

So GMRS radio has this special blend to where the repeater capability makes it more useful, interesting, and potentially capable than mere CB or FRS radios. The radio units are generally cheaper to get into than Short Wave HAM radio gear. Now the FCC does require users of GMRS frequencies to have a license. The individual user license for GMRS cost $70, is good for ten years, it covers the applicant's household, does not require taking a test, the form can be filled out online, and the turn around for approval may be same day to next day. You will be issued a call sign with this kind of license (and when talking on GMRS, the FCC requires making one's call sign known about every 15 minutes).

Okay, the license requirement is a little bit more barrier to entry than CB or FRS, but the repeater capability makes it all worth it, and as licenses go it's not exactly onerous. Here are some relevant FCC links:

FCC Info - General Mobile Radio Service (GMRS)
FCC forms - form 605 for GMRS
FCC License Manager site

For those that want to go a bit deeper on the subject, here's a good video that explains what a repeater is:

Repeater 101 for new Amateur Radio Operators

Now here's the other part that makes GMRS more interesting than CB or FRS radio, here's an excerpt from the above FCC info link about GMRS:

In 2017, the FCC expanded GMRS to also allow short data messaging applications including text messaging and GPS location information.

Now that's the good and exciting news about GMRS, the bad news is it doesn't seem like anyone in the GMRS community has implemented such features yet. But that's okay, because for something like async text messaging, I don't think the barrier to getting that operational will be so tough.

And in a GMRS repeater network organization conversation that I listened in on, the topic of discussion on a particular Sunday evening is what new capabilities would GMRS users like to see, where the top request was text messaging. If someone can get it implemented, getting the community to uptake it shouldn't be too much of a hurdle (the barrier will be getting the organizations that operate repeaters to agree to letting their repeater be used for text messaging purpose).

Why is text messaging such a big deal as a form of comms? Because when implemented properly, the sender party and receiver party do not have to be in real-time communication with each other. The text message could be posted to a server, where the receiver is eventually notified or checks in on the server and sees the message. If you are in the outback where your cell phone connectivity is dead, but your GMRS radio can hit a repeater, and you need to communicate with family members back at home, then sending a text message to them would be a great way to keep them informed as to your status.

Garmin makes a plus $400 device that enables text messaging over Iridium satellites, but the satellite service cost $11 to $15 per month:

Garmin inReach Explorer+, Handheld Satellite Communicator

Doing the same thing with GMRS radios and repeaters would be much cheaper. Here is a handheld GMRS radio capable of communicating over repeater channels that is less than $60:

BTECH GMRS-V1 GMRS Two-Way Radio, GMRS Repeater Capable, with Dual Band Scanning Receiver

And here is a $200 50 watt GMRS radio that might be even better for excursions into the outback:

BTECH Mobile GMRS-50X1 50 Watt GMRS Two-Way Radio, GMRS Repeater Capable, with Dual Band Scanning Receiver

Now one can see that these GMRS radios are not featuring any ability to do text messaging, and as I mentioned above, it doesn't look like the GMRS community has that up and going yet.

The Short Wave HAM enthusiast have had a packet radio and various services built on top of that, text messaging and SMS gateways being one of them, for literally decades. With the advent of the Internet and cell phone SMS text messaging, the packet radio scene waned for a long stretch, but in recent years interest among HAM enthusiast has come back around to packet radio. Here's a video that goes into HAM packet radio:

Packet Radio (Post Apocalyptic Internet?)

There's an entire layered communication stack involved in the implementation of packet radio - and I don't want to take any of that on at all. All I care about are:

• async text messaging
• 9-11 like service for summoning emergency assistance in the outback based on text messaging capability
• GPS location info posting (if one is equipped with a GPS receiver device) and based on text messaging capability
• DNS servers list retrieval - as based on text messaging capability

All of these, relying on a text messaging substrate, can be implemented on top of dirt simple analog Morse Code with some framing around it for sake of automated computer processing - where a Raspberry Pi single board computer implements the encoding/decoding, a FE Pi Audio V2 hat connected to the Pi, as well as the modulation of the radio with a bit of custom circuitry - the Pi Zero and FE Pi hat combo will connect to the radio in place of a mike. Here's a YouTube video where a HAM enthusiast implemented this combo in conjunction to a VHF radio (but the approach can be duplicated and applied to a GMRS radio):

Packet Radio Raspberry Pi build and demo

That would amount to the necessary hardware solution - what remains is writing the software. There would be a client-side implementation and a server-side implementation. Assuming one is doing text messaging by connecting to a repeater that is within range, a computer server will be configured to listen to the repeater - waiting for and filtering the traffic for text message transmissions.

The server software can be imagined to be something kind of like Twitter - one can post brief text messages to the server, which it retains. The server can be connected to the Internet and could use an SMS gateway to relay the text message on to some family member's cell phone. And/or family members could "ping" the server over GMRS too, where the server would text message back any recent message received. This could all be fashioned to work like the POP3 protocol or some such (heck, could just wrap existing Linux email services to serve in this role).

Keep in mind, to keep the implementation absolutely dirt simple, the bottom layer transport is analog Morse Code, so the band width of all this will not be anything to write home about. But it should be able to accomplish the goal, and thus be something to GMRS text home about.

One can also imagine that a GPS hat could be added to the Raspberry Pi stack so that a text message could include GPS location info, so there's that.

(A GMRS radio manufacturer could get slick with this and roll the entire solution into an integrated radio product.)

So what is the DNS server list retrieval all about?

Well, this is where am anticipating an Internet that becomes so hostile to Patriots that it's no longer feasible to count on a Patriot web site DNS being listed in any of the approved (allowed) DNS servers. And in fact, Patriot web sites might find they frequently have to keep changing out their IP (i.e., shifting around and squatting on any IP they can find available for use for as long as they can).

In such a scenario the problem becomes: how do end-users find out the IP addresses of Patriot web sites?

Well, Patriots could start using text messaging servers operating on GMRS text messaging as repositories of DNS server list - servers that will provide DNS resolution for Patriot websites. Patriots equipped with the relatively low cost GMRS radio gear would have their computer connect to these GMRS text messaging servers on a daily basis to download the latest DNS server list. Augmented into their computer's DNS server list, they would then be able to resolve the DNS of Patriot web sites.

In short, this GMRS text messaging substrate becomes a supplemental augmentation for patriots to still remain on and use the Internet even in a context where they've been effectively prohibited from doing so by various autocrat authorities.

We're not entirely to this point of hostility on the Internet yet, but we're really not that far away either - again, look what they did to Gab.com.

Once again considering SW radio program broadcasting?

Also, Patriots need to start thinking (and prepping) for the eventuality of having to go back to broadcasting programs on Short Wave radio - the way William Cooper did with his famous Hour Of The Time broadcast. (BTW, the FCC does not permit radio program broadcast on GMRS frequencies, so will have to go to SW to do that.)

MILTON WILLIAM COOPER 1943-2001 RIP

You may find it hard to believe, but there was indeed a patriot movement that preceded the advent of the Internet era of podcasting, and SW broadcasting was one of the staples.

Homemade Faraday Cages

What and why a Faraday Cage? It's a metal clad enclosure that deflects radio frequency energy transmission. A Faraday Cage can be used to protect electronics devices (e.g., radios, computers, cell phones, etc.) from intense electro-magnetic burst of energy, e.g., such as an intense solar flare or an artificially detonated Electro-Magnetic-Pulse (EMP) device. (Surge protectors can be used to protect electronic equipment from intense power spikes as caused by lightening strikes.)

Are very intense solar flares or EMP burst really something to prepare for? Will leave that to the reader to decide.

To make a Faraday Cage, take an electrically insulating box, say a cardboard box or styrofoam ice chest, and wrap it sufficiently in aluminum foil (completely). Use aluminum foil tape purchased at the hardware store to tape down the wrapping and its seams. Or could buy a metal ammo can and line it with electrical non-conducting material. Making one out of cardboard boxes can tend to be cheaper and perhaps one might want to use an ammo can to store ammo.

The thickness of the aluminum foil can be a factor. If using supermarket aluminum foil, it may be necessary to wrap the enclosure up to 4 times. Consequently, one might prefer to order aluminum foil of greater thickness so that only one wrapping layer of the box is necessary - saving the tediousness of multiple wrappings.

Now special care needs to be applied on the sealing of the lid - because the microwave frequencies of cell phones are such that it can make it through the lid seam. If using a cardboard box, then I recommend getting one that has a lid with overlapping flanges around the box edges. If you put your cell phone in the enclosure with lid on and its still able to receive signal, then take the aluminum tape and tape over the lid seam. That should make your enclosure 100% sealed and the signal transmission should stop, and if it does, that points out that you need to work more on tightening up your lid seal. If a signal is still getting through to the cell phone, try applying more wrapping layers of aluminum foil.

BTW, am not speaking from just theory on any of this, but from putting it into practice. The funny thing was that the process started with an FM radio, which took a bit of effort to get sufficient wrapping thickness and a carefully closed lid seam, but the cell phone required extra effort still. So I've clued you into the factors to concentrate on - am confident you'll be successful too.

Now once you achieve the ability to make your own cheap Faraday Cages for your gear, you're going to realize that you need two of everything. One unit that you use every day, and the other like unit that you put into a Faraday Cage to keep it protected (e.g., an EMP event). Because if your gear is not in the Faraday Cage when an EMP event happens, then it could very likely get rendered inoperable - and an EMP event may be something that no one sees coming.

The good news is that effective Faraday Cages can be made cheaply - the bad news is that you'll need to double down on your electronics gear if you want to be serious in your prep for this. But stocking away extra radios and cell phones, and some working computer(s) is not so bad as it doesn't have to be top shelf gear - just reasonably functional, afford