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)
  • https://re-ws.pl

RSS Radio for Everyone

  • FM Audio Transmitters - Portables and Car Hands-Free
    FM Audio Transmitters - Portables and Car Hands-FreeI'm using FM transmitters for years, both portables and vehicle versions, and pretty much used the majority of types on the market, so here's how they work and which ones I recommend.How FM transmitters work?Output audio from a device via FM transmission standard: you set a frequency on […]
  • Review: Nooelec Rattlesnake 3-antenna kit
    Three antennas with magnetic mount and coax for $16:Review and observations are based on over half a year's use, summary: order from manufacturer, Amazon USA, or eBay right away. Rattlesnake kit is the best value aftermarket antenna package I ever came across. Period.Direct competitor on price ($15 on Amazon) is rtl-sdr.com's antenna kit, separate review here.First impressionsHeavy, feels good when opening the envelope:M5: Screw standard referring to […]
  • 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 units 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: rtl-sdr.com 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.

RSS Run my experiment on GENI

  • An Experimental Evaluation of Low Latency Congestion Control over mmWave links
    In this experiment, we will show how to replicate some key results relating to low latency congestion control over mmWave links. To reproduce this experiment on GENI, you will need an account on the GENI Portal, and you will need to have joined a project. You should have already uploaded
  • Using AQM to manage "temporary bufferbloat" on mmWave links
    Background 5G wireless networks work on mmWave links which suffer from highly variable capacity and intermittent outages, during which a temporary "bufferbloat" condition occurs. In traditional networks, AQM (Active Queue Management) schemes are used to overcome the bufferbloat problem. However, AQMs were not necessarily designed to address bufferbloat on mmWave
  • TCP BBR for Ultra-Low Latency Networking: Challenges, Analysis, and Solutions
    In this experiment, we will show how to replicate the key result of the following published paper: Rajeev Kumar, Athanasios Koutsaftis, Fraida Fund, Gaurang Naik, Pei Liu, Yong Liu, Shivendra Panwar, "TCP BBR for Ultra-Low Latency Networking: Challenges, Analysis, and Solutions", in proceedings of IFIP Networking 2019, Warsaw, Poland. To

RSS Crazy Danish Hacker

RSS Blog – Hackaday

  • DIY Bagpipes Made From Common Household Items
    The bagpipes, most commonly seen in their Great Highland form from Scotland, are a loud and imposing musical instrument. Known for being difficult to practice quietly, they’re not the ideal thing to pick up in these times of quarantine and isolation. But, if you must, here’s how you can craft …read more
  • Maxing Out Browser Tabs With 2TB Of Memory
    Tabbed browsing was a gamechanger, allowing users to effectively browse multiple websites at once without losing context. It proved a better solution than using multiple windows, and was an efficiency boon celebrated by all. Many of us are tab fiends, opening great numbers at a time as a habitual part …read more
  • Professional Ventilator Design Open Sourced Today by Medtronic
    Medical device company Medtronic released designs for one of their ventilators to open source for use in the COVID-19 pandemic. This is a laudable action, and there is plenty to glean from the specs (notable is that the planned release is incomplete as of this writing, so more info is …read more

RSS ZeroSec – Adventures In Information Security

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
    Enjoy!  

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

  • Sending Samples to Python from GRC using ZMQ Sink
    When we need to process some data generated by an SDR device, the most convenient approach we have currently is saving the data into a file and then reading the files from Python. However, if the requirement is to process data in real-time as they are generated from the SDR device, saving to a file […]
  • Starting Viber with too large resolution
    After installing a brand new Ubuntu 18.04 LTS on my computer, I made some adjustments to the font sizes of the operating system in order to make it better suit for my perception. However, I realized that something is wrong after installing Viber on my desktop. The GUI of the Viber application appears so huge […]
  • Truly Reproducible Research Papers
    A slide from Prof. Barry Smyth's presentationIf you perform an experiment and get some interesting results which cannot be redone and get the same results by somebody else, something is wrong with your finding. This is called reproducibility of research. If it is not reproducible, it is not science. You might think that systematic research […]

RSS AMSAT-UK

  • Coronavirus: Initiative to popularise Amateur Radio and Satellite activities
    The West India Zone Regional Coordinator for AMSAT-INDIA, Rajesh Vagadia VU2EXP, is offering students and others the opportunity to learn about amateur radio and satellites during the coronavirus lockdown. Dear students & friends, Feel Free to Learn & Ask any … Continue reading →
  • COVID-19 – AMSAT-UK Online Shop Remains Open
    Folks, it’s everywhere, and affecting everybody. We have carefully examined our processes and determined that, given the latest ‘lock down’ in the UK, that we can pretty well carry on as normal. We have checked with our printer, and he … Continue reading →
  • Amateur radio satellite spreads Fight Coronavirus message
    Indonesia’s national amateur radio society ORARI reports the ham radio satellite LAPAN-A2 (IO-86) is being used to send a Fight Coronavirus message using APRS. A translation of the ORARI post says: The satellite spreads the text message “Stay Healthy, Stay … Continue reading →

RSS Gough's Tech Zone

RSS Compass Security Blog

  • New SMBGhost Vulnerability Affects Modern Windows Systems
    A new vulnerability (CVE-2020-0796) affecting SMBv3 has been discovered. The community has started to name this vulnerability SMBGhost because everyone knows this vulnerability is present but no additional details are available. Microsoft also released the advisory ADV200005. [1]
  • Domain-Join Computers the Proper Way
    When you add a new computer, it must first join the domain. If you use its future main user to do it, they'll become the owner and be able to hijack the computer to become a local administrator in four easy steps.
  • Invoice Fraud with Everything the Bag of Tricks Has to Offer
    Sometimes, it doesn't take much for a good scam: a good story, a little persuasion, then disappear again… and sometimes, the scammers come up with tactics that come straight out of the textbook.

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 2018 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 2018 would look like. In summary, We collected 6,234 entries (13.6% decrease since 2017 🔻). We tallied 58,463 votes across these entries (12.9% decrease since […]
  • 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 100warmtunas.com. The existing domain (100-warm-tunas.nickwhyte.com) 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 […]

RSS DB6SW (KF5OBS)

  • Quick look at the NanoVNA
    For a while now there is a very inexpensive Vector Network Analyzer (VNA) called NanoVNA available from various sources. At a price point of less than 50 USD it is very affordable for hobbyists. But is it any good? The Nano VNA covers the frequency range from 50 kHz – 900 MHz, has a small […]
  • Arduino |Automatically Save Variables to EEPROM on Power-Down
    A recurring challenge for Arduino projects is that variables are volatile and will be lost completely unless previously stored to some sort of non-volatile storage such as de inbuilt EEPROM. This article shows a minimalistic approach to detect sudden loss of power and automatically store a variable to an EEPROM adress. First I should mention […]
  • Diamex Prog-S2 | Arduino IDE
    The Diamex Prog-S2 is an universal USB ISP programmer vor various microcontrollers including Atmel AVRs. This article shows how to integrate the programmer into the Arduino IDE There are a few articles on the web that talk about the Diamex Prog-S2 and Arduino. But it seemed to me like they were either outdated or faulty. […]

RSS owenduffy.net

  • WIA 4:1 current balun – further measurements
    I mentioned in my article WIA 4:1 current balun that the use of a single toroidal core in the above graphic compromises the balun. This article presents some simple measurements and analysis that question whether the balun works as so many users think. The popularity of the balun derives from the work of VK2DQ and […]
  • 4:1 current balun – identifying bad ones
    Correspondents have informed me that the balun dealt with in article 4:1 current balun – review and fix and variants are very common. This article gives a checklist of common issues and some basic measurements using an antenna analyser that should reveal some issues without breaking into a sealed assembly. Introduction Baluns are commonly employed […]
  • 4:1 current balun – review and fix
    This article reports tests on two 4:1 current balun configurations – a collaboration between Bruce, VK4MQ, and myself. Purported current balun on a single magnetic core Above is an attempt at a 4:1 current balun on a single core. Note that this is NOT wired in the insane series opposed connection of the WIA 4:1 […]