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Showing posts from 2016

My New Toy - ICOM 7300

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Pulled the trigger on this on March 26, 2016 from Ham Radio Outlet. I have not been this excited in years! REFERENCES: http://www.qrpblog.com/2016/03/icom-ic-7300-review.html

Antenna Analyzers

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This post relates to antenna analyzers useful to amateur radio operators. I will list my experiences with these in this article. Array Solutions AIM 4170 Link:  https://www.arraysolutions.com/Products/AIM4170.htm I don't recall what I paid for my AIM 4170. It is an older version and has been replaced with the AIM 4300 ($519). The AIM 4170 exceeded my expectations. It is well worth the price if you are doing any kind of antenna work or network characterization.  The software runs under Windows 7 and works very well. I have not tried to port it to Ubuntu. The following plot is from a balun I build back in '07. This plot is from an antenna feed balun I built. Here is a photo:

Driving a Balanced Antenna with an Unbalanced Coax - Why A Balun Is A Good Idea

In a recent conversation about the need for a balun on a dipole fed with coax, the comment was made that no balun is needed because the dipole radiates in a balanced manner. Well, maybe... If a dipole is positioned above uniform ground and there are no trees, hills, fences, buildings, or powerline poles, then the statement above might be. However, the real world has trees, has hills, fences, wet and uneven ground, and powerline poles. It would be rare to have one side of a dipole driving the same free-space radiation impedance as the other side. If there is an unbalance, then the outer shield of the coax will radiate RF to make up the difference. An easy way to think of it is to imagine that one side of the dipole radiates 10 amps of RF and the other side radiates 9 amps due to the imbalance. The difference of 1 amp has to get made up. It gets radiated from the outside of the shield of the coax. Stated differently, the coax center conductor carries 10 amps. The inner shield carri...

Discombobulation & Recombobulation of W7YV Shack

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Here are some photos from 2007 when I rewired a good part of my shack. See Webster's definition of  discombobulation . Discombobulation Starting Recombobulation In Process Recombobulation Complete

SDRPlay Radio Installation Notes

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Overview These notes pertain to the installation and implementation of an SDR (Software-Defined Radio) on Linux and Windows-based machines. I was able to get the SDRPlay device installed for Windows and for Linux. Windows Installation Early on, my attempts to install SDR software on a Linux Ubuntu 14.04 machine failed due to, apparently, missing modules on the workstation. So, I decided that, if I could get it to run under Windows, it would prove that the device worked and would give me confidence that it could be installed under Linux. The Windows 7 Pro installation went well and I was able to get an SDR running in that OS. Linux Ubuntu 14.04 Installation Linux was tricky. The following links were useful to get this running: http://cubicsdr.com/ http://sdrplay.com/linux.html https://github.com/cjcliffe/CubicSDR/wiki/Build-Linux http://www.sdrplay.com/linux.html The order of the steps was not correct in the Build-Linux document. In short, the support...

Another Key For My Collection

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Just pulled the trigger on my first Begali straight key.

Operating Remote Receiver and Local Transmitter with Digital Modes

Over the past few years, many SDR receivers have been put online and can be accessed over the Internet. This allows one to monitor the bands from receive locations far from the operator's local area. This is very useful to determine if your signal is getting into an area. I have used it to monitor the Wyoming Cowboy Net from an SDR receiver in Sedona, AZ ( http://w7rna.dyndns-remote.com:18901/ ). It occurred to me that one could use a remote SDR receiver to counter problems with local noise. In order to test this concept, I've installed two programs on my Ubuntu 14.04 Linux box, as follows: FLDIGI(1) - a powerful digital mode encoder/decoder program PULSE AUDIO VOLUME CONTROL(2) - a software package that allows one to direct audio from various sources to various outputs. Once these are installed, the web-based SDR receiver can be chosen from the site: websdr.org The audio produced by the web page is routed, using the Pulse Audio application, to the FLDIGI s...

Ham Radio and the Raspberry Pi

This post is an effort to collect resource links for the use of the Raspberry Pi with Amateur Radio. This post will be updated with new links as time permits. Resetting a Forgotten Password See:  https://www.perplexity.ai/search/teach-me-how-to-reset-the-pass-UheGoyMCQ4.JsA2bU34yAg I have had to do this a few times.  How to Reset a Forgotten Password on Raspberry Pi If you've forgotten your Raspberry Pi password, there are several methods to reset it, depending on whether you can still access the system or not. Below are step-by-step instructions for both scenarios. If You Can Still Log In (Auto-Login or Another User Account) If your Raspberry Pi is set to auto-login, or you can access the system with another user account that has administrative (sudo) privileges, you can easily reset the password: Open a terminal window. Type the following command, replacing <username> with your actual username (commonly pi ): text sudo passwd <username> Ent...

Directional Discontinuity Ring Radiator and Other Magnetic Loops (Part One)

I have been thinking for some time that I would like to operate on the 160 meter band. I have a loop antenna of, about 268 feet perimeter. It resonates between the 80M and 40M bands. As such, it is hard to tune in the 160M band and most of the power is used to warm up the tuner. Recently, a friend of mine, Larry Anderton,  WA7YLI , remembered an odd antenna called a Directional Discontinuity Ring Radiator. Never having heard of the antenna by that name, I researched the topic and found some useful references (see below). Another friend, Jeff, McGrath, KG7HSN , has been searching for alternatives to large, highly visible, antennas in his yard. This antenna might be a solution. A few days ago, I had a QSO with Rich, K8NDS , of Prescott, AZ on 40M. He was running about 500 watts into a magnetic loop antenna. He was S9+10dB here in Salt Lake City. His QRZ page shows aerial drone photos of his antenna farm. He has had incredible results with this kind of antenna and has written a ...

Packet Radio on Raspberry PI

This post is a placeholder awaiting more detail. I intend to setup a Raspberry PI, a Baofeng radio, and a Kamtronics KAM modem to handle NTS digital traffic. More later...