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The Technology of “Influence” – Part 5 VHF Radio Modems

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Introduction

In my novel “Influence”, the lead character J@ck Tr@de performs various hacking tasks. In the book he spends a lot of time securing his connections, hiding his identity and hiding his location. In this series of blog posts, I’m going to talk about the various technologies mentioned in the book like VPN, the Onion Browser, Kali Linux and using VHF radios. I’ve talked about HTTPS,  VPNs, the Onion Browser and Kali Linux so far, now we’re going to discuss VHF Radio Modems.

Very High Frequency (VHF) is a radio band used by both commercial and amateur radio operators (on different frequencies). Often if you see people using small handheld radios then chances are they are using VHF. This frequency band works line of sight and doesn’t require a very large antenna to work quite well. Like any radio frequency you can transmit and receive digital data over the air, just like a cell phone does. You can buy fairly inexpensive VHF radio modems which can be used to connect a computer to the Internet via a VHF radio.

In this article we’ll look at these in a bit more detail and discuss why J@ck finds these useful.

For anyone interested, my book is available either as a paperback or as a Kindle download on Amazon.com:

Paperback – https://www.amazon.com/dp/1730927661
Kindle – https://www.amazon.com/dp/B07L477CF6

Why Does J@ck Use These?

In the previous articles we have J@ck accessing the Internet from a coffee shop Wifi using HTTPS, a VPN and the Onion Browser. With all this security, why doesn’t J@ck feel secure? As we mentioned before you want to consider security as an Onion where the more layers you have protecting you, the more secure you can feel. However the good hackers always feel paranoid and worry about being traced. In this case J@ck is worried, what if the NSA, FBI or some other agency can track his Internet usage back to the coffee shop’s wifi?

J@ck doesn’t know if anyone can do this or if anyone is actually looking for him. By having a homeless person plant a Raspberry Pi with a VHF radio outside the coffee shop and then J@ck accesses that via a VHF radio modem attached to his laptop, J@ck can be upto 2 km away from the coffee shop, as long as he has line of sight.

This way if the people in the black SUVs show up, J@ck can see them, be warned and escape. Most importantly then he will know someone is looking for him.

The downside for J@ck is that each layer of the security onion adds overhead and latency that slows down his Internet access. With all this security in place J@ck can only access the Internet very slowly.

Strictly speaking to use these frequencies you should have either a Ham or Commercial Radio license. But then if you follow the license rules, you need to identify yourself every 30 minutes, and J@ck is certainly not going to do that. In the scheme of things, J@ck considers the penalties for illegally operating a radio, the least of his problems. There are radio modems for UHF and 900 MHz as well, J@ck could use these as well. As long as the radio is cheap enough to be disposable.

Can the NSA Catch J@ck?

If the NSA can trace J@ck’s Internet traffic back to the coffee shop. Perhaps via a compromised Tor exit node and a compromised VPN, then what can they do?

If the NSA suspect J@ck is using a VHF modem, then rather than sending the SWAT team into the coffee shop, they could have three vehicles with radio direction finding equipment move into the area quietly and then they could triangulate J@ck’s true location from the emissions from the VHF radio attached to his laptop.

J@ck’s hope is that they wouldn’t do this the first time, so if the G-men do show up at the coffee shop then he would assume they would either find his Raspberry Pi/Radio Modem or guess that he was doing this and then use the radio vans the second time.

J@ck also limits his time at each coffee shop, so that the Feds have less time to set this all up and trap him.

Summary

Catching hackers is a game of cat and mouse. Since J@ck is the mouse he wants to be as elusive as possible. VHF modems are just another tool to make it harder to trace back to J@ck’s location and catch him.

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Written by smist08

January 24, 2019 at 9:12 pm

Getting My Amateur Radio License

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Introduction

I recently passed the exam to get my amateur (ham) radio license. This article is a bit on my experience with taking the course and writing the exam, as well some thoughts on ham radio. People spend a lot of money on cell phones, but most of what they do is done routinely for free by dedicated radio hobbyists. After all a cell phone is just a radio running on frequencies bought up by the cell phone providers.

Why?

There is a perception that amateur radio is an old obsolete dying hobby. That is consists of people using old tube radios trying talk to people far away with lots of interference and poor sound quality.

Why would anyone use ham radio when you can talk to anyone reliably on Skype or FaceTime? Didn’t ham radio only make sense back in the days when long distance calls were prohibitively expensive? Now even most phone plans are quite inexpensive and use the Internet to communicate. So why are the number of amateur radio licenses growing year over year? In the US the number of licenses issued each year is growing at a rate of about 1%, not Internet growth, but pretty steady for something that requires preparing for and writing a written exam.

Here are some of the main reasons for the continuing interest in amateur radio:

  • Disaster preparedness. Most amateur radios can operate off batteries and don’t require cell phone towers, Internet connections or even A/C power.
  • Better radios. There are a proliferation of new radios on the market, at much lower price points (under $100)  and a great many features including computer connectivity, digital channels and more efficient power.
  • Volunteer infrastructure. To use your cell phone you typically pay $75/month to someone for your ability to use their cell phone towers and such. In the amateur radio world many clubs operate repeaters (think amateur cell phone towers) and Internet connections allowing long distance communications with voice or even e-mail from low powered portable radios.
  • Cell phone coverage often isn’t as good as advertised. I do a lot of hiking and mountain biking. Most of the places I go, there is no cell phone coverage. However here on the Sunshine Coast if I get line of sight to the ocean I can probably hit one of the Nanaimo repeaters and communicate. The only other alternative is satellite phones and these make cell phones seem inexpensive.
  • Ability to build your own equipment and experiment. The world of cellphones is very locked down and DIY is not allowed at all. In the world of amateur radio if you have the correct license, you can build your own radio, you can heavily customize your equipment, you can build your own antennas and generally do a lot of experimentation and customization. If you have an interest in understanding how things work and playing with electronics, then this is a great playground.

Licensing

To get my license I took a course offered by VECTOR in Vancouver to prepare and write the basic amateur radio exam. This was a great success and I greatly enjoyed it. VECTOR is an emergency radio non-profit society for the city of Vancouver. The course was taught by a number of VECTOR members usually someone different for each section. This gave a good mix of perspective and provided a good variety over the five morning sessions. The details of this process are a bit different by country so the details here apply specifically to Canada. The basic exam is 100 multiple choice questions, you can take practice exams here. The course covers the main areas of the exam which are: Rules and Policies, Basic Electronics, Antenna Systems, Radio Wave Propagation, Interference and Suppression, Operating Procedures and Station Assembly Practices and Safety. The whole course and exam are theoretical and don’t involve touching a radio whatsoever.

I did pass the exam. If you get 70% then you get access to all frequencies above 30MHz and if you get 80% then you don’t have any frequency limitations. I got over 80% so I can use any amateur frequency band. My call sign is VA6SMI. I have to use this to identify myself in any communications.

To actually build your own radio you need the advanced certification which I might try to get next year. The other qualification you can get is Morse Code. Up till ten years ago this was part of getting a basic license but isn’t required anymore.

Future

I think a lot of the current popularity of ham radio is driven by a wish to be independent of cell phone providers and a wish for much more DIY in our communications. As recent fires, hurricanes and earthquakes have demonstrated the cell phone infrastructure is rather fragile and can take quite some time to get up and running again. During all these emergencies, ham radio was the main form of communications. With global warming, fires and hurricanes will become more common and a need for emergency communications becomes more and more important.

Separately amateurs are adding more and more functionality into ham communications with better digital protocols and speed. They are adding better volunteer infrastructure to support longer distance communications and Internet connectivity. The radio hardware market has gotten much more competitive recently with the addition of several Chinese manufacturers that have driven down prices and driven new innovation.

Will we reach a point where we have “smart” ham radios like we have “smart” phones? Will we be able to run apps like Facebook on our ham radio? Will be be able to use them as ubiquitously as we use our phones? Will we one day be able to break the hold of the cell phone providers and eliminate all those expensive subscription plans? It might take some time but we are slowly moving in that direction. Certainly the ham radio frequencies can’t handle that volume of traffic, but perhaps for those willing to pass the basic radio exam we will start to get some freedom from the current cell phone hegemony.

Summary

I enjoyed the process of getting my ham radio license. I’ve ordered a radio and look forward to getting on the air when it arrives. It was fun reviewing basic electronics and learning more about antennas and radio wave propagation. The rules and regulations part wasn’t bad, once you get the hang of what they are looking for, the questions are quite easy.

Now I’ll see if I’m better connected once I’m out in the woods. Plus I’ll be able to communicate during power outages (we had one today that also took out local cell phone coverage).

 

Written by smist08

October 21, 2017 at 12:47 am