Hi,

I am a longtime ham first licensed in 1955 as KN2PAA and then K2PAA I was 13 years old, ham radio led me to a lifetime of engineering, which provided great satisfaction.

I am now a retired OG, continue to chase DX, and operate mainly on the HF bands in CW, Sideband, and Digital. I am proud to have implemented my Visual Antenna Analyzer for my shack. Here is a brief history of its development. 

As a result of hurricane damage to my Cushcraft R7 vertical antenna, I needed an instrument that could help with the rebuilding, repair, and tuning of this multi-band unit, but I could not afford the price of a commercial analyzer that could run several hundred dollars.  I decided to research and design one. The finished product worked so well that I am now pleased to offer my work with both hardware and software to our amateur community.

I chose an Analog Devices AD9850 synthesizer module and an Arduino Uno R3 microcomputer. These devices combine with my custom-designed shield to provide signal interfacing, detection, amplification, measurement, and interfacing to a advanced visual PC control and display program.

The AD9850 is a highly integrated device that uses advanced DDS technology coupled with an internal high-speed, high performance, D/A converter, and comparator, to form a complete digitally programmable frequency synthesizer. It generates a spectrally pure, frequency/ phase-programmable, analog output sine wave.

The Arduino Uno R3 is a programmable microcomputer/controller that provides the on-board control for the AD9850, extracts the data from my custom shield, and communicates with the PC display program.

The idea of using the Arduino for processing was a good choice. It is Inexpensive and powerful for its uses, and many amateurs have one already.  Using the Shield I developed,  provides a way to adapt the versatile Arduino Uno micro-computer to visually measure an antenna's Standing Wave Ratio (SWR) characteristics and efficiency. The shield is a direct plug-in to the Arduino Uno and provides plug-in mounting for the AD9850.

A PC program provides a unique display of the antenna characteristics and many options such as single frequency control of the scanner for RF output for your bench testing, printed scans, antenna length modification calculation, and signal filtering and smoothing, and antenna Effective Radiated Power. 

 I realize that most of us are very cost-aware with purchases for our hobby. I have therefore made this shield available as a low-cost kit, including the shield PC card, all shield components connectors, and sockets. . Software for Uno R3 control and the visual PC display is also included, with complete documentation, assembly instructions, microcomputer examples, and uses. However, we do produce a complete tested unit with Arduino R3 and AD9850 ready to use.

 I hope that it is useful in your shack and adjusting your antennas. I recently saw an article from MFJ Enterprises that stated their number 1 selling device was antenna tuners. A tuner works much better if the antenna is near the required resonate values. As you can see I have tweaked my antenna farm using this device for a low reflected power and low SWR. You can do the same for a little cost. For more information contact me at bill@K2PAASTUDIO.com , 73's Bill.