skip to main |
skip to sidebar
My first attempt at writing an Arduino sketch that transmitted a WSPR message using an AD9850 DDS Signal Generator module, whilst successful required the WSPR message to be generated using the WSPRcode.EXE and then manually edited into the Arduino Sketch before compiling the code. Ideally, I'd like to be able to read the position and time from the NMEA string from a GPS, encode the message and then transmit it automatically - OK there are niceties such as a User Interface and LCD to contend with!
Looking back at the Etherkits website, they appear to have a module available which has an SiLabs Si5351 Clock Generator mounted into a breakout, as do Adafruit, however they also supply an easily integrated Class Library. Until a recent C# online course at work, I didn't really understand what C++ classes did and how to use them, so it's time to experiment as I've got the example code to compile without error.
I've also got some building to do as I've got some QRP Labs low-pass filter modules to build for 5 and 10 MHz together with a Kanga / M0XPD Si5351 Shield for the Arduino.
Having decided to buy the Yaesu SCU-17 USB Sound Card Interface for the FT-817, which provides a dedicated USB sound card, serial port and PTT switching etc., I tuned my receiver to 10.13870 MHz and shortly afterwards received an off-air signal from IK2CMN over several minutes (as shown in the WSJT waterfall display below).
Setting my own callsign was a doddle and shortly afterwards I managed to get the OpenBeacon to transmit "G0VRM IO93QT" in QRSS into the dummy load, however it's not quite as clean as the off-air signal. Following the instructions, I uploaded a WSPR string and it worked first time!
Notice that there are two entries for G0VRM, however one is 35 dB down and is probably some oddity of the radio being so close to the transmitter, although it appears to be very stable! Looking promising, however connecting the beacon to an external antenna via a Z-match proved to be unsucessful.
Whilst wandering around the 2016 G-QRP Convention at Rishworth with Richard G0GLZ, I spotted a box on one of the stalls, and having talked to the stallholder established it was a QRSS (very slow Morse) beacon transmitter that had at one time been used in Senegal in West Africa. At this point I decided that perhaps this project wasn't for me, it was promptly bought (partly on my behalf) by Richard G0GLZ - I did consider "The one that got away" as the title of this entry...
Although the manufacturer appears to have retired the OpenBeacon kit and have removed it from their website, the documentation and driver software are still available from http://etherkit.github.io/openbeacon_landing_page.html. As the name suggests, the OpenBeacon is an open-source beacon transmitter that is capable of transmitting a variety of modes which include QRSS, DFCW, Sequential Multi-tone Hellschreiber and WSPR.
The first challenge for this project was the installation of the unsigned driver software under Windows 10 Advanced Boot Menu, which required a change to the startup settings in order to disable Driver Signature Enforcement, several reboots later with the driver successfully installed, I was then able get the settings showing the previous callsign of 6W7RV.
Looking up the locator IK14LL on http://qthlocator.free.fr/index.php, it appears to be almost as West as it is possible to be and still be in Africa; and from the QRZ.com database, the callsign once belonged to a holiday rental "shack" located in a Wildlife Reserve with its own lagoon and Baobab forest (sorry, no pictures I'm afraid).
Finally, back to my own shack, after connecting the beacon up to a 50Ω dummy load (a BNC thin-wire Ethernet terminator in its previous life) and was able to hear the beacon transmission on my FT-817.
