Modifying a Laptop by Embedding an RTL-SDR and FunCube Dongle

Blogger “French Fry Cattaneo” wanted a portable laptop with built in SDR capability. To achieve this he opened up his Panasonic ToughBook CF-30 laptop and embedded an RTL-SDR FubCube dongle into the laptop using the space left by unused expansion ports.

Cattaneo connected the two SDRs to a small hub and soldered the usb hub connections directly onto a laptop USB port. He also installed an external SMA connector for the RTL-SDR and connected the FunCube’s antenna port to a cellular antenna that was built into the laptop.

He notes that there could be RF interference issues from the laptop, but has so far had no trouble receiving the strong signals he is interested in.

Laptop with built in RTL-SDR and FunCube Dongles
Laptop with built in RTL-SDR and FunCube Dongles

Micheal Ossmann’s Software Defined Radio Course

Micheal Ossmann, creator of the HackRF is starting an online video course on the topic of software defined radio (SDR). His course will cover GNU Radio and will help you to learn the fundamentals of digital signal processing. The first video has been released and in this video Micheal shows how to set up a broadcast FM receiver in GNU Radio.

To do the exercises in the course you will need a HackRF or other similar SDR radio. Most exercises involving reception only should be compatible with the RTL-SDR with some small modifications relating to things like the changing sample rate.

FlightAware Introduces PiAware for use with RTL-SDR and dump1090 on a Raspberry Pi

FlightAware is an online service providing real time flight tracking. The flights are primarily tracked by volunteers who run ADS-B decoding hardware which is networked through the internet to the FlightAware servers.

Now FlightAware have written in to RTL-SDR.com to let us know about their new PiAware software which enables a Raspberry Pi running dump1090 to contribute data to the FlightAware network. Dump1090 is a popular RTL-SDR compatible ADS-B decoder program for Linux systems.

A major perk for running their software and contributing data is that FlightAware will buy you a licensed copy of PlanePlotter.

The press release provided is quoted below.

If you are running an inexpensive Raspberry Pi ADS-B receiver with dump1090 then you can install the PiAware Package from FlightAware to freely view nearby flight traffic and transmit this data to FlightAware’s tracking network.  Most aircraft within Europe by 2017 and USA by 2020 will be required to have ADS-B transmitters onboard.
FlightAware’s user-hosted worldwide ADS-B receiver network tracks about 90,000 unique aircraft per day and feeds this live data into the FlightAware website in combination with other public/private flight tracking data sources.  FlightAware has over 500 user-hosted ADS-B sites online across 60 countries, with top contributors tracking over 10,000 aircraft per day.  To see how ADS-B data is put to use, check out the FlightAware Live Map.
The PiAware installation process takes only a few minutes.  If you don’t have PlanePlotter, you can download it and then send FlightAware your installation’s serial number and we’ll buy you a license.  FlightAware will also give users a free Enterprise Account ($90/month value) in return for installing PiAware.
flightaware
FlightAware Real Time Map Example

Roundup of Software Defined Radios

New software defined radio (SDRs) products are popping up every few months these days so we thought we'd compile a big list of available SDRs as there are a few people who were bitten by the RTL-SDR bug and are now looking to upgrade.

For each SDR we compare the cost, frequency range, ADC resolution, maximum instantaneous bandwidth, whether or not it can TX and if it has any pre selectors built in. Here is a quick guide to what some of these metrics mean.

Frequency Range: The range of frequencies the SDR can tune to.
ADC Resolution: Higher is better. More resolution means more dynamic range, less signal imaging, a lower noise floor, more sensitivity when strong signals are present and better ability to discern weak signals. Some SDR's give their resolution in ENOB which stands for effective number of bits.
Instantaneous Bandwidth: The size of the real time RF chunk available.
RX/TX: Can the radio receive and/or transmit.
Preselectors: Analogue filters on the front end to help reduce out of band interference and imaging.

* - Denotes top choice for high value

General Use Software Defined Radios

We define general use SDRs as ones with a wide frequency range and with no focus on any specific frequency band.

R820T RTL2832U a.k.a RTL-SDR*

RTLSDR_PCB

Cost: $10 - 22 USD
Frequency Range: approx. 24 MHz - 1766 MHz (below 24 MHz available on RTL-SDR.com V3 dongles)
ADC Resolution: 8 Bits
Max Bandwidth: 3.2 MHz / 2.4 or 2.8 MHz max stable.
TX/RX: RX Only
Preselectors: Uses tracking RF filters on the R820T2 chip.
Release Date: August 2016

The RTL-SDR is still the best 'bang for your buck' software defined radio out there. While it was never designed to be used as a general purpose SDR in the first place, its performance is still surprisingly good. If you're on a budget or are just starting out with SDR or radio this is the one to get. (Link)

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Using an RTL-SDR as a Cheap Entropy Source

One of the many uses of the RTL-SDR is as a random number generator for generating entropy. Entropy is needed in computing for many application such as in encryption and security.

Noel Bourke has written an article on his blog about using the RTL-SDR as an entropy source on Linux. Noel uses RTL-Entropy and shows how to set up Linux to use the RTL-SDR as the entropy source for /dev/random.

Receiving NTSC Analogue TV with GNU Radio and an RTL-SDR

Over on GitHub user kik has uploaded a tutorial and code showing how to decode NTSC analogue TV in GNU Radio and an RTL-SDR. The tutorial is in Japanese, but Google translate should be good enough to understand the text. Kik shows us what GNU radio blocks to use and provides the python code needed to display the images on a simulated scope.

If you just want to receive analogue TV signals, try TVSharp.

gnuradiontsc
GNU Radio Decoding NTSC and showing images on a Scope

HackRF Initial Review

The HackRF One is a new software defined radio that has recently been shipped out to Kickstarter funders. It is a transmit and receive capable SDR with 8-Bit ADC, 10 MHz to 6 GHz operating range and up to 20 MHz of bandwidth. It can now be preordered for $299 USD. We just received ours from backing the Kickstarter and here’s a brief review of the product. We didn’t do any quantitative testing and this is just a first impressions review. So far we’ve only tested receive on Windows SDR#.

Unboxing

Inside the box is the HackRF unit in a quality protective plastic casing, a telescopic antenna and a USB cable. We show an RTL-SDR next to the HackRF for size comparison.

HackRF + Telescopic Antenna + USB Cable + Box (RTL-SDR Dongle Shown for Size Comparison)
HackRF + Telescopic Antenna + USB Cable + Box (RTL-SDR Dongle Shown for Size Comparison)
Back of the box
Back of the box

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Reverse Engineering Wireless Wall Outlets And Automatically Cloning OOK Signals

Wireless wall outlets are electrical outlets that can be turned on or off by a wireless remote. Fabien is an experimenter who was looking for a way to control the power of his home devices from a remote location using HTTP. He thought of building his own from scratch, but quickly realized that the device would need to be certified for insurance purposes. Instead he bought a cheap commercially made certified wireless wall outlet and reverse engineered the protocol using an RTL-SDR.

To do that he used the existing OOK-Decoder software available on GitHub. From the analysis provided by OOK-Decoder, Fabien was able to successfully reimplement the transmission using an AVR microcontroller and 433 MHz transceiver circuit from Sparkfun.

After being successful with this, Fabien decided to take the project a step further and create the OOKLONE – a device that could automatically clone any 433.92 MHz OOK signal and replay it. The video below shows the OOKLONE in action.