Category Archives: Station Equipment

Articles about Radios, Amplifiers, Tuners and related Ham Station Equipment. Fixed, Portable and Mobile Station Equipment Articles are included.

Homebrew an Antenna Analyzer

If you’re like me, then you try to be judicious with your $$$. Ideally, it would be great to spend $ and get the highest quality in return. But, the world does not work this way. So, if I am going to spend $$$ (on a scale of $, $$, and $$$), I want to make sure not only am I obtaining quality, but also multi-functionality. In other words, it’s easier for me to spend more money when I feel like my purchase is not exactly a swiss-army knife but also not a one-trick pony.

I could be wrong, but antenna analyzers kind of feel like a one-trick pony to me. When I first strung up my Buckmaster 7-band OCF dipole, I borrowed the RigExpert AA-30 from Greg W1TEN, in order to measure the VSWR,  since I wasn’t thrilled about spending $200 for the analyzer. Especially because I would rather put that money towards a Heil headset and foot pedal (to be ordered for Xmas 2017).

At the October Board of Directors (BoD) meeting, Fred AB1OC mentioned that in the Nov 2017 issue of QST, there was an article entitled “Build Your Own Arduino-Based Antenna Analyzer” by Jack Purdum W8EEE and Farrukh Zia K2ZIA. The attractive thing about this design is the authors quote a price point of $50. The major components are comprised of an Arduino, AD9850 Direct-Digital Synthesizer (DDS) board, and TFT display. Additionally, on the main website, one can also download the associated software to load on the Arduino. So, this leaves the user with the experience and satisfaction of homebrewing a really useful component for the shack. There seems to be a lot of documentation on the assembly, parts, etc. so this makes it relatively easy for the user.

Homebrew Antenna Analyzer
Completed assembly of analyzer
Homebrew Antenna Analyzer
View of Arduino, PCB, and components for analyzer

A downside is that the number of components required seems to be somewhat large as seen from Farrukh’s website which could potentially be overwhelming if you are just beginning. The authors also quote that one helpful component is purchasing their own custom PCB for the job itself. Though this is not essential, it may aid in the build.

Having not built this yet, I would say this would be an intriguing build for someone. I would certainly like to tackle it and have added it near the top of my to-do list since it seems like it can be accomplished within a weekend.

A Cheaper Alternative?

After I read the article, I emailed Mike AB1YK to let him know about it. He replied with yet another option in the form of a PDF by K6BEZ who claims to accomplish the same feat in < $50. Definitely attractive! It’s built on the same premise: AD9850 DDS board, Arduino, etc., but seems to use fewer components. Instructions also seem to be located here. 

Some pitfalls of the build from the PDF link provided above:

  • I located some Yahoo forums discussing that the analyzer as spec’d out did not seem to work for some builders. It’s unclear if the schematics were incomplete or if it’s due to another reason entirely.
  • The build does not seem to be that much cheaper. For instance, the PDF lists the AD9850 DDS as being $4 on eBay. Having looked there myself, as well as on Amazon, the going rate seems to be in the neighborhood of $18-$19. Given this, along with looking up some of the other items in the bill of materials, the price point seems to approach $50 pretty quickly.

If I endeavor upon this, I will be sure to document and write another article about it. If someone attempts the “cheaper option”, I would be interested to hear how well it works.

Happy building!

Brian AB1ZO

Portable Satellite Station 3.0 Plans

We’ve made about 250 contacts with our Portable Satellite Station 2.0 and we have worked 106 grids which should be enough to earn a Satellite VUCC. We are working on a set of upgrades to create our Portable Satellite Station 3.0 which will support ISS Crew Contacts and be a 90th percentile satellite ground station. You can read more about our 3.0 upgrade plans via the link below.

Fred, AB1OC

Portable Satellite Station 3.0 Plans
Portable Satellite Station 3.0 Plans

Source: A Portable Satellite Station Part 5 – Plans for Our 3.0 Station

Raspberry Pi Satellite Rotator Interface

We’ve been using our Portable Satellite Station 2.0 for some time now and it works great. One area that can be improved is the interface between the MacDoppler Satellite Tracking program we use and the GHTracker application which controls the Green Heron Engineering RT-21 Az/El Rotator Controller in our setup…

Source: Raspberry Pi Satellite Rotator Interface | Our HAM Station

The Raspberry Pi is an inexpensive computer and control platform for many Ham Radio projects. We recently used a Raspberry Pi 3 to build an interface between the MacDoppler Satellite Tracking Software in our Portable Satellite Station and the Rotator Control System points the ground station antennas during satellite tracking. We put together an article about how we went about this project and some details of the hardware and software we used to put a Raspberry Pi 3 computer together for our project.

Fred, AB1OC

Remote Control Ham Station Enhancements

As explained in a previous article, we have been working on enhancing our Remote Control Ham Station system. The upgrades include additional remote client options, better remote networking via the Internet, and better integration with our microHAM system.

Source: Remote Operating Enhancements | Our HAM Station

As part of the fall upgrade plans at our station, we have completed quite a few enhancements to the Remote Operating Gateway and associated client devices in our station. The upgrades include:

You can read more on our Stationproject Blog about our Remote Control Ham Station Enhancements.

We try to do some station upgrades in the fall of each year to maximize our operating fun during the winter months. We always welcome members who want to join in on our projects as a means to learn about station building. More to come as we make progress with our planned projects.

Special thanks to Dave, K1DLM who has helped us with ideas for several aspects of this project.

Fred, AB1OC