A browse through his collected works will tell you that [El Kentaro] loves to build electronics into interesting enclosures, so when he realized there’s enough room inside a 150 ml plastic syringe to mount an ESP8266, a battery, and a copious amount of RGB LEDs, the “Packet Injector” was the inescapable result.
Granted, the current incarnation of this device doesn’t literally inject packets. But [El Kentaro] wasn’t actually looking to do anything malicious, either. The Injector is intended to be a fun gag for him to bring along to the various hacker cons he finds himself at, like his DEAUTH “bling” necklace we saw at DEF CON 26, so having any practical function is really more icing on the cake than a strict requirement.
In the end, the code he came up with for the Adafruit Feather HUZZAH that uses the FakeBeaconESP8266 library to push out fictitious networks on demand. This is a trick we’ve seen used in the past, and makes for a relatively harmless prank as long as you’re not pumping out any particularly unpleasant SSIDs. In this case, [El Kentaro] punctuates his technicolor resplendency with beacons pronouncing “The WiFi Doctor is Here.”
But the real hack here is how [El Kentaro] controls the device. Everything is contained within the syringe chamber, and he uses a MPL3115A2 I2C barometric pressure sensor to detect when it’s being compressed. If the sensor reads a pressure high enough over the established baseline, the NeoPixel Ring fires up and the fake beacon frames start going out. Ease up on the plunger, and the code detects the drop in pressure and turns everything back off.
If this build has piqued your interest, [El Kentaro] gave a fascinating talk about his hardware design philosophy during the WOPR Summit that included how he designed and built some of his “greatest hits”; including a Raspberry Pi Zero enclosure that was, regrettably, not limited to external use.
Sometimes the best projects are the simple, quick hits. Easily designed, fast to build, and bonus points for working right the first time. Such projects very often lead to bigger and better things, which appears to be where this low-power temperature beacon is heading.
In the world of ham radio, beacon stations are transmitters that generally operate unattended from a known location, usually at limited power (QRP). Intended for use by other hams to determine propagation conditions, most beacons just transmit the operator’s call sign, sometimes at varying power levels. Any ham that can receive the signal will know there’s a propagation path between the beacon and the receiver, which helps in making contacts. The beacon that [Dave Richards (AA7EE)] built is not a ham beacon, at least not yet; operating at 13.56 MHz, it takes advantage of FCC Part 15 regulations regarding low-power transmissions rather than the Part 97 rules for amateur radio. The circuit is very simple — a one-transistor Colpitts oscillator with no power amplifier, and thus very limited range. But as an added twist, the oscillator is keyed by an ATtiny13 hooked to an LM335 temperature sensor, sending out the Celsius and Fahrenheit temperature in Morse every 30 seconds or so. The circuit is executed in Manhattan style, which looks great and leaves plenty of room for expansion. [Dave] mentions adding a power amp and a low-pass filter to get rid of harmonics and make it legal in the ham bands.
Beacons are just one of the ways for hams to get on the air without talking. Another fun way to analyze propagation is WSPR, which is little like an IoT beacon.
Continue reading “Temperature Sensor And Simple Oscillator Make A Value-Added HF Beacon”
John Perry Barlow, founding member of the Electronic Frontier Foundation and Freedom of the Press Foundation, died on February 7th, 2018. To say that he left his mark on the Internet, and by extension modern culture, is something of an understatement. He may not be a household name, but between this activism (online and off), lectures, written work, and various entrepreneurial projects, his 70 years of life were surely not wasted. Barlow was once quoted as saying “I want to be a good ancestor”, and by pretty much any metric it would seem he made good on that goal.
To mark his passing, [Moritz Metz] came up with a rather unusual memorial. Using a bit of code on an ESP8266 board, he created a device that would broadcast out Barlow’s “A Declaration of the Independence of Cyberspace” line-by-line in the form of 228 WiFi SSIDs. Perhaps not the most effective way to get Barlow’s words out to the people, but we’ll give him extra points for style.
The code itself is based on FakeBeaconESP8266, which as the name implies, allows the user to create fake WiFi networks. to broadcast the manifesto of your choosing, you need only add in the appropriate
sendBeacon() lines at the bottom of the code. It would appear that prefixing each line with a number is required to make devices scanning for networks show the lines of text in proper sequence. At least on the devices demoed, anyway.
Just to be clear: you should definitely not do this. Jamming up the local environment with a bunch of fake networks is a pretty terrible idea. But as a memorial for a man who occasionally claimed to be an anarchist, you could do worse. Plus we have to admit “Giants of Flesh and Steel” is an awesome name for a network.
Continue reading “ESP8266 Broadcasts Memorial WiFi Spam”
An ultrasonic beacon is an inaudible sound with encoded data that can be used by a listening device to receive information on just about anything. Beacons can be used, for example, inside a shop to highlight a particular promotion or on a museum for guided tours where the ultrasonic beacons can encode the location. Or they can be used to track
people consumers. Imagine if Google find outs… oh, wait… they already did, some years ago. As with almost any technology, it can be used to ‘do no harm’ or to serve other purposes.
Researchers from the Technische Universitat Braunschweig in Germany presented a paper about Ultrasonic Side Channels on Mobile Devices and how can they be abused in a variety of scenarios , ranging from simple consumer tracking to deanonymization. These types of ultrasonic beacons work in the 18 kHz – 20 kHz range, which the human being doesn’t have the ability to hear, unless you are under twenty years old, due to presbycusis. Yes, presbycusis. This frequency range can played via almost any speaker and can be picked up easily by most mobile device microphones, so no special hardware is needed. Speakers and mics are almost ubiquitous nowadays, so there is a real appeal to the technology.
Continue reading “Ultrasonic Tracking Beacons Rising”
While faking BLE advertising beacons using an nRF24L01+ module is nothing new, it’s become a heck of a lot easier now that [Pranav Gulati] has written some library code and a few examples for it.
[Pranav]’s work is based on [Dmitry Grinberg]’s epic bit-banging BLE research that we featured way back in 2013. And while the advertisement channel in BLE is limited in the amount of data it can send, a $1 nRF24 module and a power-thrifty microcontroller would be great for a battery-powered device that needs to send small amount of data infrequently for a really long time.
We’re not 100% sure where [Pranav] is going to take this project. Honestly, the library looks like it’s ready to use right now. If you’ve been holding off on making your own BLE-enabled flock of birds, or even if you just want to mess around with the protocol, your life has gotten a lot easier.
It is reasonably easy to make a microcontroller spit out some Morse code. What makes [pavlin’s] take on this project interesting is that it resides on a tiny USB board with an ARM processor. The design for the board is available with single-sided artwork suitable for production using simple methods like toner transfer.
The STM device has a built-in USB bootloader. It can also act as a serial port, which makes the project very simple. The only external parts are a speaker and an optoisolator. The program provides a command line interface over the serial port that you can use to program the message and set other options like speed and the delay between messages. The code is available on GitHub.
You might argue that a beacon shouldn’t need a USB port, and we’ve seen an alternative that fits the bill. If you want a much larger Arduino-based keyer, we’ve seen those, too.
[m0xpd] got his hands on an inexpensive AD9850 DDS Module from eBay but needed a way to control it. He took inspiration from the projects that used a PIC microcontroller, but decided to add his own twist by using a Raspberry Pi to build a multi-mode beacon transmitter.
At the center of this breadboarded circuit lies the green AD9850 module. To its left is a level converter he built to get the 3.3V levels from the RPi board to work with the rest of the 5V hardware. The signal then feeds into a QRP amplifier and a low pass filter.
He didn’t start from square one when it came time to write the code for the RPi. Instead he grabbed an Arduino sketch for the very same DDS and ported it over to Python. The first test signal was his call sign sent in Morse code at QRSS speeds. But he also managed to get Hellschreiber messages working, making it a multiple-mode device.
[via Solder Smoke]