Ham Radio Maker

EU1KY Antenna Analyzer

EU1KY Antenna Analyzer (1)

Wednesday, 03 April 2019 19:00

Building an EU1KY Antenna Analyzer

Written by

So I got my Technician license April 2018 and wanted to get started in the amateur radio 2M band. Knowing that I would want to make a good antenna, I figured that I would need an antenna analyzer. I looked at the costs of analyzers on the market and decided to DIY. That’s when I found the EU1KY.

Assembled EU1KY Antenna Analyzer
My assembled EU1KY Antenna Analyzer

I assembled the analyzer using the required instructions for the EU1KY open source project (EU1KY wiki page) after ordering boards for the RF unit (I have extra boards for sale on my Ebay Site).

Under the hood
Under the hood

Note: The RF front end board mounts onto an
STM32F746G-DISCO Development Board (available from Digikey.com for about $60). Under the connectors for the RF board there are some surface mounted jumpers. The board comes with them soldered onto SB3/SB5. Move them to SB1/SB4 and then check them for continuity. Check that SB3/SB5 are non-continuous.

Jumpers on stm32f7-discovery board
Move jumpers on stm32f7-discovery board

Connect I, V and Gnd from RF board to blue audio on Discovery board like this.

For calibration, an Open/Short/Load (OSL) test kit is needed. I built mine from some spare SMA PCB board components. The 50 Ohm load has two 100 Ohm resistors in parallel and can be made more attractive by using 0805 SMD resistors. You could even do three 150 Ohm resistors in parallel to achieve the 50 Ohm target value.

OSL

Afterwards, I built a 2 meter ground plane antenna. 

2m Antenna
2 meter ground plane antenna

Measurment

Used analyzer to scan 144Mhz – 148 Mhz …

The results:

S11 Graph
S11 graph
SWR graph
SWR graph

I welcome any discussion on this project. Just add comments below or email me at my arrl.net address (callsign ke0rje).

BITX20@groups.io Feed

Feed not found.
 

Buy RF Front End Board Kit for EU1KY Antenna Analyzer


David Richards Blog

Dave Richards AA7EE

  • The GM3OXX “Oxo” Transmitter
    As well as the small stash of finished projects that grace my living space, I also have two small boxes containing various boards. Some of them are boards from part-finished projects that didn’t work. For whatever reason, I ran out of steam and, instead of troubleshooting them, put them carefully into a small box along […]
  • Ugly Construction!
    Here’s a little project I put together on a whim about 18 months ago. It was my tribute to the unlicensed (i.e. pirate) beacon cluster around 4096 KHz. There were several of them operating in full force, with powers ranging from around 100mW to a watt or so a few years ago. Their heyday was […]
  • Modifying the Tut 80 for Varactor Tuning and More Power
    Back in 2009/2010 the Arizona QRP Scorpions released a little kit designed by Dan N7VE, called the Fort Tuthill 80. It was a QRP CW transceiver, with a direct conversion receiver and a transmitter capable of putting out about 3W. It caught my imagination, and I just had to build it. I have never had […]

Frequency VFO synthesizer Microb v.4

Frequency synthesizer Microb v.4 (Microb v.4S)

This looks pretty awesome. Might have to get one.

Manhatten Construction si5351 VFO by AA7EE

si5351 VFO by AA7EE

This si5351 Manhatten style constructed VFO is really slick

uBitx v5 Un-boxing