This site is my personal blog and project repository.

If you are looking for the old Cowichan Valley Linux Users Group, check the side navigation. This site contains links to various projects that I either created or contribute to.

You will also find my Github page and Youtube channel here. Contact: cwg@cowlug.org


Latest News

EU1KY Antenna Analyzer

Posted on: September 1, 2018, in AllHam Radio - SDR

This page is a description of the modifications made to the EU1KY antenna analyzer project.
The FAA-450 Antenna Analyzer is an open source project built from STM32-F7 Discovery board. It has the following features:
  • Colour TFT LCD with capacitive touch.
  • HF/VHF(UHF) frequency coverage (500KHz-500MHz.
  • Built-in TDR function.
  • Multiple scanning curves including SWR.

The analyzer uses DSP technology to analyze the sampled signal and derive the their magnitude ratio and phase difference.

Full open source software is available at bitbucket.org/kuchura/eu1ky_aa_v3.

Development is done by cross compiling for the STM32F746 board on windows (Embitz IDE) or linux (makefile with arm-none-eabi-gcc). The generated F7Discovery.bin file is uploaded to the device using ST-Link loader.

ST-Link loader is available from STMicroelectronics. For windows, you will also need to get the STSW-LINK004 utility and STSW-LINK007 drivers.

List of Custom Software Modifications by VE7IT

Modify splash screen to display QSL card.

TDR chart
Splash screen


To replace the splash screen, create a BMP file exactly 480x272 pixels in size.
Place it in the Src/analyzer/lcd/bitmaps folder.
Make sure it is the only BMP file in the folder, then run the bmp2h.py python script.
This will create a logo.h file which will be included in the project when it compiles.

Modify the signal generator screen.
The analyzer can function as a continuous wave signal generator over a frequency range of 500kHz to 450MHz. Signals above 150MHz are actually using the 3rd harmonic of the internal source.

Generator Screen
Reformated Signal Generator screen

The signal levels are low (0.1 to 0.2vpp), but do radiate when attached to an antenna!. Using the generator mode and a frequency counter, one can adjust the internal crystal calibration factor to get the generator accurate within a PPM or so.

Tapping on the frequency display opens an onscreen keypad where a new frequency in kHz may be entered. Steps of plus and minus 500kHz, 100kHz or 5kHz may be activated by pressing the onscreen row of 6 keys under the frequency display.
Several lines of diagnostic information are displayed that can be used to troubleshoot the hardware receivers, the OSL calibration and the VSWR calculation code. One can also perform a screen save to aid in debugging.

Modify the TDR screen to display coax length in metric and imperial units.

TDR chart
TDR scan showing both metric and imperial lengths

Modify the highlighted ham bands to represent the North American frequency ranges available.
See panvswr2.c. Also, modify the SWR panoramic display to position the cursor bar on the point of lowest SWR on the displayed graph.

SWR chart
SWR scan of 6M vertical

Files / Downloads / Links

Free windows IDE for ARM: https://www.embitz.org/.
STMicroelectronics ST-Link software: https://www.st.com/en/development-tools/st-link-v2.html.
Modified project source files: eu1ky_aa_v3.zip (10.0Mb).
You can download John Coppens ON6JC/LW3HAZ excellent Linsmith program from http://jcoppens.com/soft/linsmith/index.en.php
VE7IT linsmith remote control patch: linsmith-remote.patch for linsmith-0.99.28 (19.2kB).
Analyzer kit/assembled supplier: www.elekitsorparts.com



QRP Labs LimeSDR Enclosure.

Posted on: March 27, 2018, in AllHam Radio - SDR

I recently got a LimeSDR board and also bought a QRP Labs case for it. The QRP Labs case brings all the RF connectors out to the front and rear panels and also includes heatsinks for the chips and a case fan.
Assembly instructions are here.

.
Parts list:
    1. 12pcs SMA to U.FL pigtails
    2. aluminium shell bottom (4 holes)
    3. aluminium shell top (fan cutout, 2 holes)
    4. 4 rubber pads
    5. 4 plastic screws
    6. 8 plastic nuts
    7. fan 30x30 5v with mesh
    8. pinheader
    9. heatpad (1pcs, cut later into more pcs)
    10. 6pcs heatsinks (1x + 2x + 3x)
    11. PCB panel (front, rear)
    12. 8 panel screws
    13. 4 bicolor LEDs
    14. 2 LED holders

Software: There are four software packages that I use with the LimeSDR as well as the LimeSuite from Myraid RF.

Users especially Hams should consider the HF mod https://wiki.myriadrf.org/LimeSDR_HF_Performance