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1. #LONG RANGE BLUETOOTH MODULE FOR RASPBERRY PI CODE#
2. #LONG RANGE BLUETOOTH MODULE FOR RASPBERRY PI LICENSE#

Posted in Radio Hacks Tagged antenna, kilometer, lan, long range, networking, radio, rooftop, trango, video conferencing, wifi If you need more range than a kilometer, though, it’s not too much more difficult to do once you have all the right hardware.

#LONG RANGE BLUETOOTH MODULE FOR RASPBERRY PI LICENSE#

Some of the comments in the linked Reddit post suggest that with an amateur radio license this system could be pushed much further, too. And, before anyone jumps to conclusions, apparently this is well within FCC rules as well.

#LONG RANGE BLUETOOTH MODULE FOR RASPBERRY PI CODE#

is planning on releasing a whitepaper about this build shortly, but for now you can access the source code for the video conferencing system at his GitHub page. The WiFi setup in this build is effectively just a bonus to make the conferencing system more effective. ’s employer needed a teleconferencing solution for their building, and he also created a fully open-source video conferencing solution called trango that can run on any LAN and doesn’t require an Internet connection. This setup doesn’t actually broadcast an open Internet connection, though. The antenna is placed at the top of a building which certainly helps with the extreme range as well. The build uses a 10 dBi antenna from TP-Link that’s rated for outdoor use and a single-board computer which acts as a sort of router. While most would reach for a range extender or other hardware bridge, was able to roll out a better solution for his workplace by using a high-gain antenna and a single-board computer which gets him an amazing kilometer-wide WiFi network. This of course leads to frustration where a WiFi signal can be seen, but the connection is unreliable or slow. WiFi is an ubiquitous feature of the modern landscape, but due to power restrictions on most hardware alongside the high-frequency signal it’s typically fairly limited in range. But if you merely want to replicate an existing transmitter’s signals, it might be easier to simply spoof a few button presses.Ĭontinue reading “Reverse Engineering A 900 MHz RC Transmitter And Receiver” → Posted in Wireless Hacks Tagged channel hopping, drone, long range, remote control, TBS Crossfire If you’re into decoding RF protocols, you might also want to try using a logic analyzer. Of course, that’s perfectly fine for most RC applications, as long as the user is aware of this fact. The eventual conclusion is that while the protocol is efficient and robust, it provides no security against eavesdropping or deliberate interference. ’s blog post goes into intricate detail on both the Crossfire’s protocol as well as the reverse engineering process needed to obtain this information. Luckily, brute-forcing it was not hard the checksum is most likely used to keep receivers from picking up signals that come from a different transmitter than their own. The data packets appeared to be built up in a straightforward way, but they included an unknown CRC checksum. Once that was out of the way, the next step was to figure out what data was flowing through those channels. The Crossfire uses channel hopping, and by simply looking at the register settings it was easy to figure out the hopping sequence. First, he built his own SPI sniffer using a CYC1000 FPGA board to reveal the exact register settings that the PIC32 sent to the SX1272. As it turns out, it was not trivial, but not impossible either.

This led him to ponder if the RF protocol would be easy to decode. When bought a Crossfire set for his drone, he discovered that the receiver module consisted of not much more than a PIC32 microcontroller and an SX1272 LoRa modem. The TBS Crossfire is one such transmitter, and it’s become a popular model thanks to its long-range performance. Many transmitters are available in the 2.4 GHz band, but some operate at different frequencies, like the 868/915 MHz band. For those building their own remote controlled devices like RC boats and quadcopter drones, having a good transmitter-receiver setup is a significant factor in the eventual usability of their build.