trackers

2 Articles

Tracking Boats And Ships In Real Time At The Same Time

October 22, 2020 by 15 Comments

Software-defined radio came on the hacker scene in a big way less than a decade ago thanks to the discovery that a small USB-based TV tuner dongle could be used for receiving all kinds of radio transmissions. Two popular projects from that era are tracking nearby airplanes and boats in real time. Of course, these projects rely on different frequencies and protocols, but if you live in a major port city like [Ian] then his project that combines both into a single user interface might be of interest.

This project uses an RTL-SDR dongle for the marine traffic portion of the project, but steps up to a FlightAware Pro dongle for receiving telemetry from airplanes. Two separate antennas are needed for this, and all of the information is gathered and handled by a pair of Raspberry Pis. The Pis communicate with various marine and air traffic databases as well as handles the custom user interface that knits both sets of information together. This interface was custom-built from a previous project of his and was repurposed slightly to fit the needs of this one.

This is a great project that goes into a lot of interesting detail about how the web traffic moves and how the UI works, so even if you’re not into software-defined radio it might be worth a look. However, it’s also worth noting that it hasn’t been easier to set up a system like this thanks to the abundance and low price of RTL-SDR dongles and the software tools that make setting them up a breeze.

APRS Repeaters Get The Signal Out Of Mammoth Cave

November 25, 2015 by 55 Comments

APRS Cave-Link uses the amateur radio’s Automatic Packet Reporting System (APRS) inside caves to get their position data (and other messages) out.

Imagine that you’re coordinating a large scale search-and-rescue mission in a cave. You need to know where all your groups are, and whether or not they’ve found anything. But how do they all communicate to the command center?

You’d guess radio, but you’d guess wrong. Radio doesn’t propagate well at all in a maze of twisty passages, all alike; rocks absorb radio waves, especially in the VHF/UHF range that’s best suited for most small radios. In the past, you’d run wire and transmit along it. This article runs through the options in detail. But adding miles of wire to your already heavy caving and climbing gear is a nuisance or worse.

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