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APRS becomes a more useful expedition messaging service with the addition of SMS and email gateways.

These gateways bypass the traditional APRS messaging requirement that both parties be online at the same time. With the SMS Gateway and Email Gateway, I can send a message to someone back in the world, and the message will arrive on their computing device as normal SMS or email. Critically, both gateways store messages for 24 hours and allow receivers to request unacknowledged messages be resent. This means that someone can reply to my SMS or email at any time, even when my radio is off. I just have to turn on my radio at least once per day and instruct both gateways to send me any new messages.

The Civilized Way to SOTA

I’m interacting with both gateways directly from my Yaesu VX-8DR but this thread on the Expedition Portal forums provides a good introduction of using them via APRSdroid.

APRS gateways also exist for weather reports, WhatsApp messaging, and requesting the nearest repeaters.

A Better Clipboard

One of the things I learned over the years at 2 Meter Critical Mass and other radio events is the value of a good clipboard. The Field Message Pad or Field Memo Pad or even the Field Notebook are great for my own notes, but when responding with a radio on behalf of an agency, said agency will probably have official log and message forms, and those forms will probably be on 8.5” x 11” paper. A clipboard is an important tool for making those forms usable in the field.

Many people end up with a Gibson approved Saunders Storage Clipboard. They’re nice, but too bulky for my tastes. I use a WhiteCoat Clipboard.

These clipboards are hinged, allowing them to fold in half. They are intended to be folded so that they fit in the pocket of a lab coat and protect patient information from shoulder surfing. But when folded they also fit well into a decent sized cargo pocket, or larger jacket pockets. Folding the clipboard also provides some protection to the paper itself. Even if you’re just putting it in a pack, it’s nice to be able to fold the board and not worry about the paper becoming wrinkled.

The WhiteCoat Clipboard is available with different quick reference medical stickers. None of these are extremely useful to me. I went with the EMT Edition because it has a scale for estimating pupil size, which is something I have struggled with in the past. I’ve considered printing my own stickers to put on the board – perhaps with some kind of radio reference material – but I haven’t decided what information would be useful to include.

A simple rubber band is available to secure the bottom edge of the paper. This is critical to one’s sanity in windy conditions. A pen clip to keep your Fisher Space Pen M4B close to hand completes the package.

The system is overpriced, but I am very happy with its functionality.

2 Meter Critical Mass

2 Meter Critical Mass is a monthly radio practice event at Spreckels Lake in Golden Gate Park. The practice grew out of the NERT community and sought to help people keep current with their handheld radios. I started attending on a fairly regular basis a couple years ago. We’d jump around to different frequencies on the 2 meter band and practice sending and receiving traffic.

Changing frequencies was sometimes the most difficult part of the practice. Most people, myself included, program their radios with software like CHIRP. When it comes time to do something like change to a frequency that is normally used for repeaters, and then remove the offset because you need to use it for simplex, it can be a struggle to remember the correct sequence of steps. But simple skills like that are critical in the field during an emergency.

After the struggle of getting everyone onto the correct frequency, some people would start sending traffic while others would copy it down onto standardized message forms. This is the primary role of radio operators during an emergency, but is not often practiced. The messages were often lists of medicines, the Latin names of plants, or some other gibberish that would require use of the phonetic alphabet to transmit. Somebody in the group would be picked to be the net control operator, which brought with it an entirely different set of skills to practice. Somehow I always got “volunteered” for that – rain or shine (often offering an example of why you fill your field message pad with waterproof paper).

2 Meter Critical Mass

2 Meter Crical Mass was the child of Peter McElmury, AA6SF. In November there was no practice, which I thought was odd. I had never known Peter to miss a month. But he was a Marine and it was his birthday that weekend, so I figured he was just busy celebrating. The December practice was four days ago. It turns out Peter was absent in November due to a medical emergency. At this month’s event he was walking with a cane and having trouble with motor skills, like writing, but he was in a good mood and happy to be radioing, as always. Yesterday he died.

A Brief Survey in Marin

This past Sunday I rode to Mount Tam.

The electrical grid was down throughout Marin county, and for some reason that meant the state had closed some of the roads in the park to motorized traffic. Fortunately my vehicle runs on man-power and works just fine when the power is out. I figured the closure would make the ride more pleasant and I would just slip around any gates.

As I was riding in the general direction of fire I decided it would be prudent to throw a radio in my handlebar bag. From past experience I know that my cell phone reception can be spotty at the best of times in the hills and valleys up there. I assumed that the power outages and strong winds wouldn’t do me any favors. (It turns out I was right.)

After much climbing and much wind I reached Ground Equipment Facility J-33. This abandoned Nike missile site on the West Peak of Tamalpais is a reliable site for radioing. It has been host to a couple Field Days and was the destination of last year’s SOTA trip. And it’s a nice spot to bicycle to.

J-33

The Marin Amateur Radio Society maintains an excellent network of linked repeaters that I was able to hit immediately upon turning on my radio. Despite the distance, I was also able to reach back into San Francisco. Line of site to Sutro Tower meant I had a clear, strong signal on the San Francisco Radio Club repeater W6PW. I talked to a guy on there who told me that the Marin Radio Amateur Civil Emergency Service had been activated due to the fires. I keep some of the Marin RACES simplex frequencies programmed into my radio, just in case Godzilla walks through the bridge and we have to coordinate across the bay, so I jumped over to those channels to listen for any action. After that I was able to reach out to the East Bay, and listen to the effects of the fires that had just started that day in Contra Costa County.

Line of Sight to Sutro Tower

  • Radome
  • Tam West Peak

After completing my survey of the airwaves I flew back down to sea level at approximately Mach 3, though I had to stop once for a California Highway Patrol helicopter that decided to use the gated off road as a landing pad.

It’s impressive what you can get done on a little handheld radio with 5 watts and a small antenna, assuming you can get to a good position. A bicycle is a good way to get there.

Avian carriers achieved a message delivery rate of 95% in the first World War, and were reported to reach 99% success in an Army study published in 1944.

In an article at At War on the Rocks, Dr. Frank Blazich provides a brief overview of the military use of homing pigeons and argues for their reintroduction as a response to electronic warfare.

Considering the storage capacity of microSD memory cards, a pigeon’s organic characteristics provide front line forces a relatively clandestine mean to transport gigabytes of video, voice, or still imagery and documentation over considerable distance with zero electromagnetic emissions or obvious detectability to radar. These decidedly low-technology options prove difficult to detect and track. Pigeons cannot talk under interrogation, although they are not entirely immune to being held under suspicion of espionage. Within an urban environment, a pigeon has even greater potential to blend into the local avian population, further compounding detection. The latter presumably factored into the use of pigeons to clandestinely smuggle drugs, defeating even the most sophisticated of walls.

Furthermore, pigeons provide an asymmetric tool available for hybrid warfare purposes. The low-cost, low-technology use of pigeons to transport information or potentially small amounts of chemical agents — or even coded cyber weapons — makes them a quick and easy asset to distribute among a civilian population for wider military purposes. During World War II, the British Confidential Pigeon Service of MI14(d) dropped baskets of homing pigeons behind enemy lines for espionage purposes, gathering invaluable military intelligence in the process from a wide array of French, Dutch, and Belgian civilians. Even as a one-way means of communication, the pigeon proved an invaluable military asset.

Via Schneier, who reminds that we have an RFC.

I don't know anything about, or have much interest in, high-frequency trading.

But some of the technology behind it is fascinating. This past summer the Sniper in Mahwah blog published a four part series investigating the use of shortwave radio as a low latency link in high-frequency trading. I’d call it the best piece of hacker-tourism since Mother Earth Mother Board, but I think it’s probably the only piece of hacker-tourism since Mother Earth Mother Board. It doesn’t have much competition.

I was reminded recently of John Michael Greer's comments on distributed communications.

To wit:

What would a viable long-distance communications network in the age of peak oil look like? To begin with, it would use the airwaves rather than land lines, to minimize infrastructure, and its energy needs would be modest enough to be met by local renewable sources. It would take the form of a decentralized network of self-supporting and self-managing stations sharing common standards and operating procedures. It would use a diverse mix of communications modalities, so that operators could climb down the technological ladder as needed, from computerized data transfer all the way to equipment that could be built locally with hand tools. It would have its own subculture, of course, in which technical knowledge and practical expertise would be rewarded, encouraged, and fostered in newcomers. Finally, it would take a particular interest in emergency communications, so that operators could respond to disruptions and disasters with effective workarounds at times when having even the most basic communications net in place could save many lives.

The interesting thing, of course, is that a network that fills exactly these specifications already exists, in the form of amateur radio.

This weekend I tagged along with the SFRC on their first SOTA activation.

We took a short hike up to Ground Equipment Facility J-33 on the West Peak of Mt. Tam. This was the first time I’d been back up there since Field Day 2017. I was able to get two contacts on 2 meters with my VX-8DR, and another two on 20 meters with one of the other operator’s KX3. The club has more photos.

SF Bay

  • Radome
  • 2M Contacts

SF