An Amateur Radio Survival Guide for Linux Users
I have covered only some of the more-common activities that Linux users looking to venture into the world of Amateur Radio are likely to be interested in. There are many other interesting areas of activity, and in almost all cases, there is a way to participate as a Linux user. For example:
APRS (Automatic Packet Reporting System): location-aware services are starting to emerge as our mobile telephones gain the hardware, connectivity and software required to support them. As with many things, Amateur Radio operators are ahead of the curve here as well. For more than two decades, operators have been pairing radios and modems with GPS receivers to transmit their positions to others. Initially used for local-area positional awareness during public events, the system now is interfaced to the Internet, providing a way to track people from a Web browser using Google Maps. APRS is easy and inexpensive to use, and it provides features and functionality above even some so-called modern services. On a recent trip, I was more than 100 miles away from cellular coverage, but my friends were able to track my position through the APRS system.
Satellite communications: did you know that Amateur Radio operators have satellites in space for the sole purpose of facilitating communications? With an inexpensive radio and some creative antenna work, you can communicate with an amateur satellite for the purposes of digital exchange or even analog voice calls. Linux users are not excluded from this activity. If your distribution provides the gpredict package, take a moment to install and run it. You might be surprised to see an amateur satellite passing overhead as you read this (Figure 2).
SDR (Software Defined Radio): historically, radios have been complex purpose-built analog devices that depend on a lot of filters, resonant circuits and other components. Increasing performance of these devices often means adding additional filter stages and, recently, embedding Digital Signal Processors (DSPs) to cut noise and block unwanted interference. A new generation of radio technology recently has emerged that uses very simple, wideband, general-purpose radio components and relies on the high performance of a modern PC to do all the hard work. The result is what is called a Software Defined Radio or SDR. These systems have incredible sensitivity and are extremely flexible. Several projects exist that are working to push the envelope of this new technology, but the most interesting to Linux users probably is the GNU Radio Project (see Resources).
Clearly, there are many natural interactions between the Open Source community and the Amateur Radio community, and you will be amazed and surprised at how many current projects have been inspired by Amateur Radio or adopted by it.
Dan Smith, KK7DS, is a software engineer for IBM's Linux Technology Center in Beaverton, Oregon. He enjoys playing Amateur Radio on the weekends and is the author of the D-RATS software.
Practical Task Scheduling Deployment
July 20, 2016 12:00 pm CDT
One of the best things about the UNIX environment (aside from being stable and efficient) is the vast array of software tools available to help you do your job. Traditionally, a UNIX tool does only one thing, but does that one thing very well. For example, grep is very easy to use and can search vast amounts of data quickly. The find tool can find a particular file or files based on all kinds of criteria. It's pretty easy to string these tools together to build even more powerful tools, such as a tool that finds all of the .log files in the /home directory and searches each one for a particular entry. This erector-set mentality allows UNIX system administrators to seem to always have the right tool for the job.
Cron traditionally has been considered another such a tool for job scheduling, but is it enough? This webinar considers that very question. The first part builds on a previous Geek Guide, Beyond Cron, and briefly describes how to know when it might be time to consider upgrading your job scheduling infrastructure. The second part presents an actual planning and implementation framework.
Join Linux Journal's Mike Diehl and Pat Cameron of Help Systems.
Free to Linux Journal readers.Register Now!
- SUSE LLC's SUSE Manager
- My +1 Sword of Productivity
- Murat Yener and Onur Dundar's Expert Android Studio (Wrox)
- Managing Linux Using Puppet
- Non-Linux FOSS: Caffeine!
- Doing for User Space What We Did for Kernel Space
- SuperTuxKart 0.9.2 Released
- Google's SwiftShader Released
- Parsing an RSS News Feed with a Bash Script
- LiveCode Ltd.'s LiveCode
With all the industry talk about the benefits of Linux on Power and all the performance advantages offered by its open architecture, you may be considering a move in that direction. If you are thinking about analytics, big data and cloud computing, you would be right to evaluate Power. The idea of using commodity x86 hardware and replacing it every three years is an outdated cost model. It doesn’t consider the total cost of ownership, and it doesn’t consider the advantage of real processing power, high-availability and multithreading like a demon.
This ebook takes a look at some of the practical applications of the Linux on Power platform and ways you might bring all the performance power of this open architecture to bear for your organization. There are no smoke and mirrors here—just hard, cold, empirical evidence provided by independent sources. I also consider some innovative ways Linux on Power will be used in the future.Get the Guide