It didn’t take long after the attacks on the power substations in Moore county, North Carolina for the old Civil Defense guys in the ham radio community to start ranting about the “Shit Hitting The Fan” in their email lists. Talking about how State emergency response groups are woefully unprepared or – more to their point – disconnected from the ham radio community.
While we disagree with the statist approach to their solutions, they’re not wrong about the problems. If power, Internet, and cellphone systems all go out, that leaves people vulnerable. Elderly people, people with disabilities, people living with food insecurity, etc. You know, the working class.
Prior to 9/11, the number one threat to national security in the eyes of United States government was not from Islamic Extremists, nor “Illegal Aliens”, nor “The Chinese”, but from American white supremacists. The anti-Black racism, homophobia, xenophobia, and hatred of poor people that existed before 9/11 never went away. Instead, it was redirected towards a War on terror, a War on Drugs, and a War on “Illegal Immigration”. The hatred was focused on external perceived threats to cishet white male Christian hegemony. So now, there are power substations being attacked, likely by white supremacists.
In the case of Moore county, North Carolina there’s a possibility that the ideological target was the local LGBTQ+ community due to a drag show that was happening at exactly the same time. The physical target, however, was anyone who uses electricity. While the motivation for the attack in Moore County is yet to be confirmed, the plausibility of terrorist attacks on critical infrastructure targeted at marginalized communities in both the present and future is very real. Regardless, the effect is the same.
Due to the known fact that many police and their ilk are either fascists or simply sick bastards in their own right, it should be understood that state-based solutions to communications outages are neither tenable, nor necessarily desirable for many people.
With that said, it may be obvious to us that having a ham radio base station at the local police department monitoring for emergency traffic may not be so desirable. What may not be obvious is that police departments tend notto want people calling them over the radio either.
So what is to be done? The short, very general answer – and probably the most important – is to build dual power in the form of networks of solidarity and mutual aid. But here are a few ideas.
What already exists? NCPACKET, APRS, solar panels, batteries, flashlights, candles, heaters. What should we build? As always, build community, bases of knowledge, networks of mutual aid and solidarity. What does that look like? Queering ham radio and building Community mesh networks.
Pick up some FRS, MURS, GMRS or CB radios for your friends and neighbors. Come up with a comms plan and practice.
Following the police murder of a comrade at the Weelaunee Forest, we endorse the statement which can be found below.
As for our own words, we support the rights of people to communicate freely and to enjoy nature. We oppose mass surveillance and the Carceral State. Aside from that, we love trees. They hold our antennas.
We call on all people of good conscience to stand in solidarity with the movement to stop Cop City and defend the Weelaunee Forest in Atlanta.
On January 18, in the course of their latest militarized raid on the forest, police in Atlanta shot and killed a person. This is only the most recent of a series of violent police retaliations against the movement. The official narrative is that Cop City is necessary to make Atlanta “safe,” but this brutal killing reveals what they mean when they use that word.
Forests are the lungs of planet Earth. The destruction of forests affects all of us. So do the gentrification and police violence that the bulldozing of Weelaunee Forest would facilitate. What is happening in Atlanta is not a local issue.
Politicians who support Cop City have attempted to discredit forest defenders as “outside agitators.” This smear has a disgraceful history in the South, where authorities have used it against abolitionists, labor organizers, and the Civil Rights Movement, among others. The goal of those who spread this narrative is to discourage solidarity and isolate communities from each other while offering a pretext to bring in state and federal forces, who are the actual “outside agitators.” The consequence of that strategy is on full display in the tragedy of January 18.
Replacing a forest with a police training center will only create a more violently policed society, in which taxpayer resources enrich police and weapons companies rather than addressing social needs. Mass incarceration and police militarization have failed to bring down crime or improve conditions for poor and working-class communities.
In Atlanta and across the US, investment in police budgets comes at the expense of access to food, education, childcare, and healthcare, of affordable and stable housing, of parks and public spaces, of transit and the free movement of people, of economic stability for the many. Concentrating resources in the hands of police serves to defend the extreme accumulation of wealth and power by corporations and the very rich.
What do cops do with their increased budgets and their carte blanche from politicians? They kill people, every single day. They incarcerate and traumatize schoolchildren, parents, loved ones who are simply struggling to survive. We must not settle for a society organized recklessly upon the values of violence, racism, greed, and careless indifference to life.
The struggle that is playing out in Atlanta is a contest for the future. As the catastrophic effects of climate change hammer our communities with hurricanes, heat waves, and forest fires, the stakes of this contest are clearer than ever. It will determine whether those who come after us inherit an inhabitable Earth or a police state nightmare. It is up to us to create a peaceful society that does not treat human life as expendable.
The forest defenders are trying to create a better world for all of us. We owe it to the people of Atlanta and to future generations everywhere to support them.
Here are some ways to support the defense of the forest in Atlanta:
The Narrow Band Emergency Messaging System is probably one of the easier digital systems to implement. In its simplest form, all you need is your radio and an Android device running AndFLmsg. Simply type your message in the app, hold your radio up to the phone speaker and press the PTT button while the encoded message plays over the speaker. This method is called “audio coupling”.
The downside of audio coupling is that it makes a lot of audible noise in your local environment. The sound is pretty annoying, too. It’s also possible for environmental noise to interfere with a good copy, although some of the modes used with NBEMS are fairly robust against noisy environments.
There are a few ways to solve this, but they all involve either more equipment, more capable radios, or both.
If you’re using a Baofeng UV-5R or similar HT, you could use an audio interface cable such as the BTECH APRS-K1. This cable is usually used for APRS, but it does work for AndFLmsg. One end plugs into the Kenwood connector socket on the radio, and the other connects into your phone with a 3.5mm TRRS connector. If your phone does not have a 3.5mm audio jack, it may be possible to use a USB-C to 3.5mm adapter, but it seems like a lot of people have trouble with this. Besides, that’s a lot of cables and connectors at that point.
Speaking of a lot of cables, you could also use a sound card interface such as the Digirig Mobile, the Wolphi Link, or possibly the EasyDigi if you want a more DIY option. It’s similar to the APRS cable, except that it’s more modular and can be used between various devices and radios, provided you have the right cables to go between them.
The downside to the BTECH APRS K-1 cable is that you either still have to manually push the PTT button, or you have to put the radio into VOX mode. This means that the PTT is triggered by audio rather than by pressing the button. This can cause the beginnings of messages to be cut off, or (in my experience) cause the radio to overheat and kill the battery, or it may completely fail to trigger the PTT at all. The other issue – and Baofeng radios are notorious for this – is that the VOX circuit may be quite laggy, which might cause the first part of a message to be cut off. To overcome this, it may be a good idea to start a message with some junk data, such as a bunch of zeros or just jumbled letters, in order to give the VOX circuit the split second it needs to activate the PTT.
Audio interfaces such as the Digirig shouldn’t give you this problem, as they are able to send the RTS signal to the radio, which activates the PTT much like a radio with built-in CAT control would be able to do.
As of this writing, it seems that the Mobilinkd TNC3 does not work with AndFLmsg.
AndFLmsg is based on a more feature rich suite of free and open source programs called FLdigi. AndFLmsg basically consists of FLmsg and FLwrap. The full desktop version can be a little more complicated to set up, but FLmsg and AndFLmsg are capable of talking to each other.
The first thing AndFlmsg shows you is a simple screen that looks like a chat interface. A mostly empty screen with a text field at the bottom where you type the message to be sent. For quick, informal messages that need to be sent from one person to another, this is perfectly acceptable.
However, AndFlmsg also supports forms. These are pre-formatted XML files, often made for particular organizational purposes. The most common form is the ICS-213 “General Message” form. (It is also possible to create custom forms, but that’s beyond the scope of this post.)
It takes about 3 minutes to send the text of John Brown’s last speech using a mode called MT63-2000L. With the BPSK31 mode, it takes almost 11 minutes to send the same text. AndFlmsg supports dozens of different modes that have varying levels of robustness, and transmit at various speeds. You’ll want to research the different modes and decide which is most appropriate for your group in any given situation. Take into consideration the length of the messages you’re likely to be sending back and forth, how long you can sit in one place waiting for a message to be transmitted, as well as both audible and RF interference in your local environment that you’ll have to deal with.
To send and image in AndFlmsg, go to the Compose View and scroll down to select the “picture.html” form. Fill out the form, and attach your picture. Tap “save to outbox” and it will take you to the Outbox view. Select your message, and then tap “TX OVER RADIO”. The encoded message will begin to transmit.
When sending images which contain text using AndFlmsg, we have observed that rotating the image 90° so that the text is vertical makes the decoded transmission 100% more legible. However, sending images with text should probably not be your primary purpose for using this system. It could be useful to send images of injuries, an area affected by flood or fire, the face of a missing person, maps, or aerial photographs for instance – in other words, things which can only be effectively expressed through images. It took more than 3 minutes to send the black and white images above.
Sending text is bound to be faster, more efficient, and less prone to error than sending images, at least in most cases we can think of.
Edit: another application has become available, quite similar in concept and usage to AndFlmsg, called Rattlegram (on Google Play Store or wherever you get your APKs). It uses a method called Coded Orthogonal Frequency Division Multiplexing (OFDM), which makes it quite fast. However, as far as we can tell, it is only possible to send text (and emojis!) not forms, images, or files.
You ever email someone about something really important? Why? You know they’re not going to read that, right? The signal to noise ratio of email is so unbelievably low that the vast majority of people rarely if ever check their inbox. Text messaging is how you generally get a hold of someone quickly.
But if you’re in a situation in which, as we’ve proposed before, your local area is cut off from cell phone and internet access – and worse yet, you are out of range of an APRS digipeater, meaning SMSGTE is inaccessible- there is yet another way for you to send an SMS text message using ham radio, this time using HF and Winlink.
It’s possible that you have stumbled across a feature provided by your cell carrier accidentally. Your phone number has an email address associated with it.
It may go without saying that you need to know the recipient’s cell carrier ahead of time in order for the message to be sent. It is necessary to plan ahead a little.
When you send an email to an address like this, the email shows up as an SMS message for the recipient. The recipient can then reply to the message as if it was a normal SMS text message.
But there may be a hitch. When you *receive* a message from a phone number, it may not be a plaintext message. Some cell providers format the messages with HTML and attach a few images and logos just to be jerks. When you’re using a 1200 Baud connection over VHF, or even 300 Baud over HF, it is difficult to overstate how LONG it takes to download these unnecessary attachments, not to mention the poorly formatted HTML message. It can take so long to receive these messages that the connection to the RMS gateway being used may time out to relieve congestion. This system is for emergency use, after all.
For this reason, it would be best to primarily use this as a one-way communication technique, e.g. to notify your loved ones, affinity groups, journalists or lawyers of what’s happening.
It would be a good idea to append such a message with something like “Due to low bandwidth conditions, please do not reply via SMS. Send an email from [known, accepted email address] instead.”
The email address must be in the “accept” list.
To add an email address to your Winlink “accept” list, send an email message to that address via Winlink ahead of time, or send your message to the contact’s known email address at the same time. Keep in mind that it may take several minutes to send an email. Sending the same email to 2 addresses doubles that time because you’re sending the same message twice.
If you need to send a message to several people, it may be possible to set up an email list. This saves your radio from sending the same message several times over at 300 or 1200 Baud. Riseup.net runs a good email listserv. You do not need a riseup.net account to use it.
We know that police and the State can shut down cell towers at any time, basically by asking the telecom companies nicely to “pretty please turn the tower off because there’s an emergency”. We also know that not every protest takes place in an urban setting with cell and Internet service on every block. At pipeline protests, railway blockades, and forest occupations, cell service can be anywhere from spotty to non-existent.
With ham radio and APRS, it is possible to get a message out to people who need to know what’s happening when you’re in the digital dark. The best part about this technique is that the people you contact basically don’t need to know *anything* about ham radio.
1. a valid call sign (sorry pirates, sometimes that’s just how it goes.) (UPDATE: I actually tried setting up APRSdroid with a fake call sign, and NOT entering an APRS-IS password, and it seems to have worked fine. I did not transmit over RF. Tired old reminder that illegal things are illegal, own risk, etc.)
2. a device with Internet access, and a device capable of sending and receiving SMS text messages.
3. Important phone numbers. National Lawyers Guild, outside support team, a friendly reporter, your mom, etc. You’ll be adding these as “aliases” later on.
4. a VHF radio with APRS capability. This can be:
-A Baofeng or other basic HT, an Android phone or tablet with APRSdroid installed, and an APRS cable.
-A Baofeng or other basic HT, Android phone with APRSdroid installed, and a Modem/TNC such as the Mobilinkd. (There are options for iOS, but I don’t know what they are)
-A VHF transceiver with APRS built in, such as the Yaesu FT-3DR, the Yaesu FTM-400, or the Radioddity GD-AT10G.
How to get set up
1. Get APRS working. You can start with APRSdroid using the APRS-IS service in order to avoid transmitting your phone number on the air for no reason, and for the sake of using a stable Internet connection rather than RF. It’s up to you. However, once this process is all done, MAKE SURE you can actually send and receive packets VIA YOUR RADIO (not the Internet. [I made this mistake.])
2. Send a message (any message) to the “SMS gateway” service by entering in the callsign SMSGTE. The message format should be “@5551611312 some message”. Use your phone number, or a number you don’t mind being associated with you for a while. You have to do this at least once.
(Note that you can actually stop here and use the SMSGTE service without registering, but the following steps will add a little tiny bit of privacy, at least against anyone within RF range listening to APRS traffic, or watching a site like https://aprs.fi. And by itself, this is still useful. If a comrade really needs to get a message to their partner or family member for example, you could let them borrow your device, type in the phone number and message and hit ‘send’. They do have to know the number, or be able to find it in their contacts.)
3. Go to https://SMSGTE.org and create an account. Follow their instructions, as part of the registration process involves sending at least one APRS message.
4. At the top of the page, go to ‘User Tools’ and ‘Alias Manager’. You should see an empty list with “Name, Number, SSID” at the top. SSID isn’t necessary, but will make it easier to manage multiple conversations in your chosen APRS interface.
Doing all this allows you to save contacts and conversations as distinct message threads. So when you want to send a message to the NLG phone number, you can send it in one of two ways:
With just the Alias,
Message: @NLG My name is X, we're at Y, some of my friends have been arrested. Please send help.
or with the SSID
Message: My name is X, we're at Y, some of my friends have been arrested. Please send help.
Receiving SMS messages via APRS.
When someone receives a text message from the SMSGTE service, it will look like
If the person you sent the message to wants to reply, they *must* begin the message with your callsign and SSID such as “@[CALLSIGN-7]” otherwise it will just go straight to the SMSGTE number and never be transmitted back to you.
Pros and Cons
1. APRS is basically GPS. Even though the “P” stands for “Packet”, it’s often referred to as the “Automated Position Reporting System”. As such, most APRS devices periodically beacon out your GPS location while it’s running. This includes APRSdroid. Radios with APRS built in may be set up differently and have different options. To mitigate privacy concerns, APRSdroid has a GPS ambiguity setting, which in my experience has abstracted my position by as much as 34 miles from my actual location. so that’s…something.
2. APRS would be good for coordinating logistics that are legal, like water, food, first aid, legal observers, and media. It is extremely important to understand that these messages are sent in the clear, and over the airwaves, AND over the Internet, AND through unencrypted SMS messages. So this is very much a technique to use when the grid is down and you have an emergency.
3. APRS being useful is still reliant on beacons that are run by volunteers. There is no guarantee that wherever you go, there will be an APRS Igate that’s running and within RF range. Remember that getting your antenna as high up as possible will help you get out farther. Raise your radio up over your head, stand on top of a car, climb a tree. Do whatever you have to to get the signal out.
4. If you are within RF range of an APRS beacon, it’s possible that you will be able to *send* SMS messages, but not receive them. Unfortunately some Igates only *receive* and do not transmit.
5. while SMSGTE is automated, it is also a *service* that is run by *human* *volunteers* who can forget to pay the phone, server, or electric bill, or trip over a power cord, or get struck by lightning or any number of other things, just like anybody else. This service is correspondingly vulnerable. It’s pretty robust, but it’s not bulletproof. Hardly anything is. https://SMSGTE.org has a donation link near the top of the page.
Before the bombs started dropping on Ukraine, I was trying to write something about the ban on ham radio there. Now I’ll do the same thing, but not try to be clever or funny about it. I don’t know that this information will be particularly useful to the people of Ukraine *right now*, but it might come in handy for any of us later on.
There are essentially two ways a ban on ham radio can be enforced.
1. Jamming: basically, jamming is the deliberate interference of a radio signal by transmitting on the same frequency as the target signal, usually at a higher power. So, if you are transmitting at 5 watts, a 6 watt signal on the same frequency would drown you out. Or even a 1 watt transmitter if it is very close to the receiver. This is especially easy on FM due to a phenomenon called the “capture effect”.
We saw the use of jamming a few months ago when the Cuban government used powerful transmitters to block signals on the 40 meter band which is used for long distance communication.
2. RF direction finding: in movies and TV shows they often call this “triangulation” and it’s a real thing. If you’re on VHF/UHF your antenna most likely transmits in an omnidirectional radiation pattern, meaning your signal travels roughly the same distance in any direction. The signal is strongest at the source – near the antenna – and gets weaker as you get farther away. An attacker can find the source of your signal by the use of one or more *directional* antennas. These are antennas that have a more focused RF radiation pattern for both transmission and *reception*. Two common types of directional antennas are the Yagi-Uda antenna (featuring a large pole with a handful of smaller perpendicular bars) and the more well known satellite dish. The attacker would sweep an area, swinging the antenna in different directions to find out where the signal is strongest.
An attacker can, of course, jam a signal using these directional antennas. However, they may be just as likely to send someone over tofind the source of the transmissionand shut it down themselves.
If an attacker is jamming theseline-of-sight radio frequencies, you are probably a bit stuck.
Assuming the jammer is only working on a narrow portion of the spectrum, you can try switching to a different frequency. Coordinate with your affinity group beforehand to select contingency frequencies.
If the attacker is jamming on a huge chunk of frequency space, your only options are to switch to higher power, or switch to a different band.
It might be possible to get a signal out using different modes of operation such as CW (Morse Code) or weak signal digital modes such as JS8Call. The narrow-banded nature and other properties of CW make it easy for human ears to pick out of the noise and decipher. Weak signal digital modes like JS8Call can be decoded deep into the noise floor.
Neither of these options are *guaranteed* to be immune to jamming. It’ll depend on the situation. The only way to try is by experimentation.
Near Vertical Incidence Skywave propagation is a technique for HF radio comms that involves *lowering* your antenna, generally to between 1/4 and 1/10 of a wavelength off the ground.
To clarify: under normal circumstances, the ideal height of an HF antenna should be 1/2 wavelength above the ground. So if you’re on the 40 meter band (~7MHz), set it 20 meters up. 20 meter band (~14MHz), 10 meters up, etc. Antenna science is complicated, and there are many exceptions to this, but it’s a general rule of thumb. This allows your signal to radiate *outward* toward the horizon as much as possible, where it can reflect off the ionosphere once again beyond the horizon.
If you’re doing NVIS on 40 meters, you would want a *horizontal* dipole between 4 meters and 10 meters off the ground. For 20 meter NVIS, you would want your antenna to be between 2 meters and 5 meters off the ground.
By setting your antenna *lower* to the ground, you do the opposite. You are trying to make sure that as much energy as possible is directed skyward. Hence “Near Vertical Incidence Skywave”. This technique gets your signal
out farther than line-of-sight (VHF/UHF), but for shorter distances than normal HF propagation. It can also be used to get a signal over mountainous, or possibly militarized, terrain.
Direction finding is also more difficult with NVIS because in a way, you are using the earth as part of a directional antenna, which means an attacker’s *directional* antenna is going to have a tough time figuring out which direction a signal is coming from, as you no longer have an omnidirectional signal.