You’d think copying files between two different machines would be a relatively simple task, but it’s fraught with all sorts of subtlety and wastefulness. The rsync tool changed everything—fast, efficient, accurate file copies, right down to preserving file permissions, compressed transfer, and differential transfer—transferring only changed data. Tom will provide an introduction to command‐line rsync and a treatment of a couple of applications using it: the Grsync GUI, and the Dirvish backup system.
Topic 2/2: Quasar
Speaker: William Bell
Azuracast is an open source Internet radio automation solution deployable via Docker or Ansible. Nick will explain how he has used it to stream his own content over the Internet to enjoy on the run anywhere there is a mobile data connection.
Topic 2/2: AV1 Part Deux – Developments and VMAF
Speaker: Nick Skarott
Just over one year ago Nick demonstrated at PLUG the beginnings of the next generation open source video codec, AV1. A lot has changed in that time in the AV1 space and it’s fitting to look at the developments, and in particular, the work NetFlix has done (and then open sourced) with the University of Southern California and the Laboratory for Image and Video Engineering at University of Texas’ Austin campus, called VMAF.
As the internet grows into every corner of our lives, so too does pervasive surveillance within it. Your activity can be intercepted, analysed, and abused by many interested parties, from credit card thieves to abusive nation-states. The privacy implications of everything being networked in this way are enormous, and in most cases very poorly understood by the general public. Worse, unscrupulous and incompetent vendors take advantage of this confusion, and peddle white-labelled security snake-oil that gives users a false sense of security.
A better option for defending yourself from such surveillance is the use of the Tor network, which routes your internet traffic through multiple computers on the internet in such a way that your privacy is protected. Tom will explain the basics of how Tor works, and list some of the benefits and caveats in using it.
Joseph will talk about why Git is useful for version control. How it compares with SVN and how to use it.
The Intersection of Amateur Radio and Computing
Speaker: Giovanni Moretti – ZL2GX and Graeme – ZL2GZ
Amateur radio is a hobby of exploring the limits of radio, electronics and digital technologies. Once licensed, you’re allocated a worldwide-unique callsign and can operate (and build) radio equipment capable of international and space-based communication.
Being an interest centred on electronic communication, there’s naturally a strong overlap with computing, with Arduino and Raspberry Pi and Linux being widely used. There are many facets to the hobby ranging from the seriously technical through to providing communications support for search-and-rescue (SAR), Civil Defence and Amateur Radio Emergency Communications (AREC).
In this talk, we’ll will give an overview, including how you can:
communicate internationally from your backyard (without the Internet or cell phones)
use both voice and digital modes on-air
design and build radio transceivers and antennas
send signals 2000km using just a Raspberry Pi and a micro-transmitter.
use Linux to link into international Internet-linked DMR and DStar (digital mode radio) networks
become involved in the ongoing efforts to build a regional radio-linked TCP mesh network
Should any of these pique your interest, we’ll finish by outlining how you can become licensed.
As the world slouches slowly back towards normalcy in the wake of COVID-19, the PLUG is looking forward to resuming in-person meetings at our usual venue, hopefully sometime next month—both the lockdown and renovation work have complicated our access to the Milson Community Centre, so we won’t be able to meet there this month.
However, club President Nick Skarott has set up video conferencing software for our usage, and we are planning on holding a virtual meeting for anyone interested on Thursday the 11th of June, at 7:00pm. We’re unlikely to have a specific agenda, but the software (Jitsi Meet) supports screen sharing, which seems to work well, so if there’s something you’d like to demonstrate for the club, you’d be most welcome to do so—or, just come along to say hello to some familiar faces.
There are a few ways to connect to Jitsi; Nick has produced a helpful PDF. It works from either a mobile phone and a laptop. If you don’t have a working camera and/or microphone, that’s OK; you’re most welcome to come along and observe anyway. There’s also a text chat in the window, if need be.