radio, electronics, security, silly hacks
In 2014 i have released the first publicly available software that could monitor unencrypted voice calls on a TETRA network (and also some data: SDS, status etc). This software was called telive. Previously the network operators intentionally did bother with encryption. This pushed network operators to use it. The world got more secure. While better Continue reading "Listening to TETRA encrypted…
Youpot is a novel proxy-back honeypot for catching worms, that uses the attacker IP as a pure honeypot. No need to implement any service emulation, we just redirect the connection back to the attacker s IP on the same port he connected to us, sit back and enjoy the show 🙂 More info here: Youpot https://github.com/sq5bpf/youpot
LoRA mesh networking is gaining a lot of popularity, especially Meshtastic. The available modules have very lax bandpass filtering. This can be fixed by a simple filter from a tinned still can and some semirigid coax. The construction is based upon the W1GHZ Altoids Tin Filters publication for 901MHz, but tuned a bit lower. Construction Continue reading "Altoids tin bandpass filter for 868MHz…
The uSDX+ is a nice little transceiver from china based on the uSDX project. It is cheap, works on 8 bands, is based on opensource software, and has enough place inside the case to do some modifications. And if it breaks, it is easy to fix (probably easier than many analog radios). So let s see Continue reading "uSDX+ simple modifications"
The (tr)uSDX has hardware to measure the power amplifier voltage/current/input power. Since the output power is also measured, it can calculate and show efficiency. This is very useful for tuning the class-E output stage, and is also useful in the field to see battery voltage and other parameters. I have an uSDX+ transceiver from China. Continue reading "Adding an INA219 power monitor to a chinese…
The (tr)uSDX transceiver has a builtin SWR meter. It will measure SWR and forward/reflected power. This is very useful in the field, because there is one less device to carry. I have an uSDX+ transceiver from China. Let s add the SWR meter to it too. To make this mod you need some manual and soldering Continue reading "Adding an SWR meter to a chinese uSDX+ transceiver"
This is a demo of a working replica of the Great Seal Bug. As far as i know this is the only attempt to make a working replica, not only a nicely looking prop. I am a licensed radio amateur (callsign SQ5BPF), therefore the device dimensions were scaled to make it operate on the amateur Continue reading "Demo of a working replica of the Great Seal Bug on the 23cm band"
This is the third part of articles about the Great Seal Bug (also called “The Thing”). These articles will cover: history, theory of operation and a practical reconstruction of this device. This part is about building a working copy of the Great Seal Bug To my knowledge this is the only publication about making a Continue reading "The Great Seal Bug. Part 3: Building a working copy of The Thing"
This is the second part of articles about the Great Seal Bug (also called “The Thing”). These articles will cover: history, theory of operation and a practical reconstruction of this device. This part is a short explanation the theory of operation. The FBI has unclassified the initial report about the Great Seal Bug [3]. It Continue reading "The Great Seal Bug. Part 2: theory of operation"
This is the first part of articles about the Great Seal Bug (also called The Thing ). These articles will cover: history, theory of operation , a practical reconstruction of this device and a working demo. This device, even 75 years later, is still often mentioned at security publications and conferences. On 4 August 1945, at Continue reading "The Great Seal Bug. Part 1: history"