Liên kết hữu ích

  • MARTIN - G8JNJ - ECLECTIC AETHER - Adventures with Amateur Radio
  • Owen Duffy VK2OMD (ex VK1OD) - Good practical information relating to Electronics, Antennas, Feedlines, Baluns & just about everything else
  • Steve G3TXQ - Home of the Broadband Hexbeam and 1:1 Balun common mode impedance charts
  • Tom W8JI - Lots of practical antenna information and theoretical analysis
  • Dan N3OX - Lots of antenna practical construction information (especially verticals) and theoretical analysis
  • Adam AB4OJ/VA7OJ - Excellent information relating to Icom Radios and associated items
  • Alan K0BG - Everything you will ever need to know about mobile operation and compact antennas
  • Phil AD5X - Lots of very interesting articles and construction projects
  • Ian GM3SEK - Lots of practical design info. Especially these pages on cost effective common mode choke design
  • Jim KY9C - Loads of design and measurement information relating to common mode chokes
  • Chuck W1HIS - More notes on ferrite common mode chokes. Showing what you need to do to reduce EMI problems
  • L.B Cebik W4ML (SK) - The best resource for antenna design and modelling (free but you need to create a login account)


  • Motherboard Article: Creating an IMSI Catcher with an RTL-SDR
    Motherboard, an online technology magazine has recently run an article titled "With $20 of Gear from Amazon, Nearly Anyone Can Make This IMSI-Catcher in 30 Minutes". The article describes how an RTL-SDR together with the IMSI-Catcher Linux software can be used to collect IMSI numbers from cellphones connected to a nearby cell tower. The IMSI is […]
  • Measuring Broadcast FM Multipath Distortion with an RTL-SDR
    Over on GitHub user jj1bdx has just released a new tool called rtl_power-fm-multipath which can be used for estimating broadcast FM multipath distortion with an RTL-SDR. Broadcast FM multipath is caused when a signal is received from multiple directions due to it reflecting off and refracting through physical objects like buildings and terrain. As the reflected/refracted signals […]
  • Es’hail-2: First Geostationary Satellite with Amateur Radio Transponders Successfully Deployed
    Today SpaceX have successfully launched and deployed the Es'hail-2 satellite which is now in geostationary orbit. This launch is special for amateur radio enthusiasts because it is the first geostationary satellite that contains an amateur radio transponder on it. The satellite is positioned at 25.5°E which is over Africa. It will cover Africa, Europe, the […]

RSS Radio for Everyone

  • Portable Bluetooth Audio Signal Receivers
    Receive an audio signal up to 50 feet / 15 meters - best replacement for wires, also work as hands-free in a vehicle. Hands-on guide and five types tested and compared: cheap from China, for Hi-Fi, and midrange and expensive hands-free. Regardless of locale and prices, these four types cover most flavors on the market.What […]
  • Maximum USB cable length
    Question often comes up, Answer: 27 feet / 9 meters with RTL-SDR dongles:For testing, I tried four separate RTL-SDR dongles in image above: v3, Nooelec Mini 2, Nooelec E4000 SMArtee and regular Nooelec SMArt.USB connector cable is crucial, as mentioned in a previous post detailing stuff I'm happy with, blue 5 feet / 1.5 m […]
  • RTL-SDR Dongles Image Gallery
    Studio Photos of over 20 RTL-SDR dongles on the market:More than 200 high-resolutions PCB, case and comparison images by clicking here.
  • Nooelec Ham It Up Plus upconverter / noise source
    An upconverter lets you hear signals below the tuning range of RTL-SDR dongles, so signals less than 30MHz, that's the entire shortwave / medium wave / longwave spectrum will be audible with a suitable antenna. Works by adding 125 MHz to received signal, so a station on 3MHz will show up at 128 MHz, which falls […]
  • About Software Defined Radio and RTL-SDR
    What?Software Defined Radio: computer or smartphone does signal processing, not individual and expensive components as with traditional radios. The cheapest way into radio reception, best bang for the buck.RTL refers to chipset converting analog radio signal to digital form.RTL-SDR dongles are digital TV tuners re-purposed for radio signal reception; with a special driver and free software, […]

RSS Run my experiment on GENI

  • SSL Stripping Attack
    In this experiment, we will set up an SSL stripping attack on GENI and will demonstrate what the attack does to the encrypted communication between a client and a site. We will examine what information an “attacker” can see by using the attack and under what conditions the attack works.
  • Passive sniffing in 802.11 networks
    In this experiment, we will observe the level of confidentiality provided by three kinds of WiFi networks - an open WiFi network, a WEP network, and a WPA network. You will have to download and install Wireshark to run this experiment. You should do this before your reservation on the
  • The spanning tree protocol
    In this experiment, we will see how broadcast storms can occur in a network with bridge loops (multiple Layer 2 paths between endpoints). Then, we will see how the spanning tree protocol creates a loop-free logical topology in a network with physical loops, so that a broadcast storm cannot occur.

RSS Crazy Danish Hacker

RSS Blog – Hackaday

  • It Might Be Possible To Build A Stingray With A Raspberry Pi
    If there’s one thing that’s making you insecure, it’s your smartphone. Your smartphone is constantly pinging the cell towers, giving out your location and potentially leaking your private information to anyone with a radio. This is the idea behind an IMSI catcher, or Stingray in common parlance, and now you too can build one with […]
  • Flywire Circuits at the Next Level
    The technique of assembling circuits without substrate goes by many names; you may know it as flywiring, deadbugging, point to point wiring, or freeform circuits. Sometimes this technique is used for practical purposes like fixing design errors post-production or escaping tiny BGA components (ok, that one might be more cool than practical). Perhaps our favorite use […]
  • Fail Of The Week: When the Epoxy-Coated Chip Is Conductive
    Every once in a while, you’ll find some weirdness that will send your head spinning. Most of the time you’ll chalk it up to a bad solder joint, some bad code, or just your own failings. This time it’s different. This is a story of weirdness that’s due entirely to a pin that shouldn’t be […]

RSS ZeroSec – Adventures In Information Security

  • Taking a Step Back
    Not an overly verbose or detailed post, more a note or place marker to say I'll be taking a step back from writing and blogging for a few months. I need to take some time out from writing, researching and assisting to try and find myself(as cheesy or weird
  • ZTH-CH3: Troubleshooting?
    A skillset that many people look at when you work in IT or have some form of interest in technology is the ability to 'fix' things.
  • ZTH-CH2: - Security For Everyone
    I will explain the importance of using strong passwords, what multi-factor/two-factor authentication is and why it is important and also explain some more security tips.

RSS Genesys Guru Blog

  • Genesys Integration on The Wire (IOTW)
    Following on from a previous post on Genesys Management 2.0 here I’ve been doing some additional work on integrating Genesys environments with Elasticsearch. The result is what I call Genesys Integration on The Wire (IOTW).     Integration on The Wire (IOTW) is a technology which enables system level integration based on a “zero touch” […]
  • Genesys Management 2.0
    Hi – I’m back! Unfortunately, due to client confidentiality I’ve not been able to blog about Genesys work projects for a few years. Let’s change that .. This post is about something I have been looking at for several years in the form of a shelved project which gets events from Genesys components via the […]
  • 2016 Xmas Light show using Raspberry Pi Controller

RSS fetch( ); decode( ); execute( );

  • Saving Selected GNURadio Data using an External Trigger
    When using GNURadio Companion (GRC) software package with a software defined radio (SDR) to capture radio signals, the usual approach is to save the incoming data stream into a file so that they can be processed later other other tools. However, the fast sample rate of SDR devices such as HackRF causes GRC script to […]
  • 3.5 inch LCD Display on Raspberry Pi
    I received a 3.5 inch LCD display which can be attached to the Raspberry Pi B+ device. It can be attached to the GPIO port of the RPi and use it as a display and as a touch screen for input. Installing drivers for the device was straightforward. Following are the steps I took to […]
  • A Signature Image for Documents
    While filling forms and preparing documents on the computer, I come across needs to put my handwritten signature on the document. In such cases, the printing of the document, signing it by hand and then scanning it to produce the soft copy is too much. It is useful to have an image of the signature […]


  • ESEO ready for launch
    ESA have released a video of the European Student Earth Orbiter ESEO satellite which carries an amateur radio payload. ESEO is expected to launch as part of Spaceflight’s SSO-A SmallSat Express mission, on a SpaceX Falcon 9 from Vandenberg Air … Continue reading →
  • Es’hail-2 / P4-A positioning and IOT phase started
    Following the successful launch on November 15 of Es’hail-2 on board the SpaceX Falcon 9 launch vehicle, Mitsubishi (MELCO) and Es’hailSat will begin the In Orbit Testing (IOT) program once the satellite has been positioned in a test orbital slot … Continue reading →
  • JY1SAT Launch Information and Dashboard
    JY1Sat is an enhanced 1U FUNcube. It has been developed for the Crown Prince Foundation in Jordan. The spacecraft has been named in honour of the Crown Prince’s grandfather, King Hussein, who operated using his personal amateur radio callsign which … Continue reading →

RSS Gough's Tech Zone

  • Review: Cowin HE5A SportFree Active Noise Cancelling Wireless Bluetooth Earphones
    With most new phones beginning to omit the headphone jack, most users have begun a mass migration to Bluetooth wireless audio solutions. Many of these are traditional headphones which are somewhat bulky, but there has been an increase in interest … Continue reading →
  • Random: Kogan vs Catch Connect LTE Speed, Crap CAT5e, Unboxing RPi3B+
    It’s been a while since I wrote my last “random” post, so I thought it was about time to put up another. After all, sometimes there are just some observations that don’t quite warrant their own posting but are still … Continue reading →
  • RoadTest Review: Molex 2.4Ghz/5Ghz Antenna Kit
    It’s been another busy weekend getting a few things done – one of which was this review of Molex 2.4Ghz/5Ghz antennas offered through the element14 RoadTest program. While antennas are probably not the most interesting devices to be testing, they’re … Continue reading →

RSS Compass Security Blog

  • Substitutable Message Service
    Have you ever said something and later regretted it? Or written an email to someone and then wished it had not happened? Or sent an SMS message but afterward desired to change its content? Well, replacing the content of previously sent SMSs is actually possible. SMS messages can be constructed in one of two modes: […]
  • Hidden Inbox Rules in Microsoft Exchange
    Contents Introduction Attack Overview Step-by-Step Detection Email Clients Administration Tools Exchange Compliance Features MAPI Editor Eradication Microsoft Security Response Center Swiss Cyber Storm 2018 Conclusion References Introduction In recent investigations, Compass recognized a raise in popularity for attackers to compromise Microsoft Exchange credentials. As one of the first steps after having obtained the credentials (most […]
  • Area41 2018 Wrap Up
    Introduction Last Friday and Saturday (15./16. June 2018), the 6th edition of the security conference Area41 (formerly Hashdays, organized by DEFCON Switzerland (, took place in Zürich. Every Compass security analyst can attend two conferences every year supported by Compass. So most of the analysts decided to go to the Area41 this year […]

RSS 0xicf

  • ClearEnergy ransomware can destroy process automation logics in critical infrastructure, SCADA and industrial control systems.
    Schneider Electric, Allen-Bradley, General Electric (GE) and more vendors are vulnerable to ClearEnergy ransomware. Researchers at CRITIFENCE® Critical Infrastructure and SCADA/ICS Cyber Threats Research Group have demonstrated this week a new proof of concept ransomware attack aiming to erase (clear) the ladder logic diagram in Programmable Logic Controllers (PLCs). The ransomware a.k.a ClearEnergy affects a massive […]
  • Flaws in Samsung’s ‘Smart’ Home Let Hackers Unlock Doors and Set Off Fire Alarms
      A smoke detector that sends you a text alert when your house is on fire seems like a good idea. An internet-connected door lock with a PIN that can be programmed from your smartphone sounds convenient, too. But when a piece of malware can trigger that fire alarm at four in the morning or […]
  • Waze | Another way to track your moves
    Millions of drivers use Waze, a Google-owned navigation app, to find the best, fastest route from point A to point B. And according to a new study, all of those people run the risk of having their movements tracked by hackers. Researchers at the University of California-Santa Barbara recently discovered a Waze vulnerability that allowed […]

RSS Nick Whyte

  • 100 Warm Tunas has a new home!
    100 Warm Tunas has found a new home this year! This year’s results, along with the past 2 years can now be found at The existing domain ( will simply perform a 301 permanent redirect to the new domain, so all existing inbound links should be unaffected.
  • 100 Warm Tunas 2017 Prediction Analysis
    🔥💯 🔥💯 Over the space of 6 weeks, 100 Warm Tunas collected a large sum of data and chugged away at it to make some predictions about what the Hottest 100 of 2017 would look like. Along the way we encountered a bug in the collection process, however data was backfilled and showed that I […]
  • 100 Warm Tunas 2017 Update 🔥💯
    100 Warm Tunas has been happily chugging away for the last month or so. I’ve obtained a fair amount of media coverage too. A couple of days back, I posted the site to the triplej subreddit. Someone replied to the post telling me my vote count was significantly less than what they had been counting […]


  • Automated Forward Gain Measurement
    This article is going to take you into the world of automation. Using MATLAB and commercial off-the-shelf bits and pieces, this article will show how to measure the forward gain of a RF device. For a long time now I had a bunch of Mini Circuits portable test equipment bits and pieces sitting around. S […]
  • Thermal Design Basics | Practical Example
    Thermal design is one of those things engineers don’t really learn in school and hobbyists often don’t even think about. This article is going to show some basic math with a practical example. One of my portable police scanners has an external 6V jack. To use it in my car I used my standard linear […]
  • AT&T go Phone Service for GSM Modules
    When playing with GSM/GPRS modules for Arduino and other platforms, one is faced with the selection of a cell phone carrier that supports such devices. This article is going to show how to use AT&T’s go phone service for GSM modules. For my SIM900 powered GPRS Shield V2.0 from seed [1] I needed to find […]


  • Co-phased collinear for 2m – discussion of phasing devices
    An exploration of a cophased collinear array with coax phasing stubs explored various structures for encouraging co-phase operation of a 3/4λ vertical over perfectly conducting earth (PCE). This article expands that set with NEC-4.2 models of some variations on the traditional Franklin form of the antenna. Let’s start with review of the traditional Franklin form […]
  • A second test of the FA-VA5 antenna analyser
    I recently acquired a FA-VA5 antenna analyser. Whilst preparing A first test of the FA-VA5 antenna analyser, issues were noticed with the user interface design / implementation. This article started off as a video demonstration of measuring the Matched Line Loss (MLL) of a 6m length of old / budget grade RG58CU for comparison with […]
  • A first test of the FA-VA5 antenna analyser
    I recently acquired a FA-VA5 antenna analyser. The analyser is a low cost kit (~A$265 including high accuracy cal kit and postage), the SM components are already fitted to the PCB, but the other components like switches, display connector etc need to be fitted. Whilst these parts are hand soldered, some pins are quite close […]