Today was my first tentative to receive the Grimeton signal here in Switzerland. I’ve been visiting the radio station a few weeks ago, therefore very interested to listen to the signal once back at home!
My equipment is a home-brew active E-field antenna based on the design published by DL1DBC (with a TL082 instead of TL07, because that’s what I had in the drawer…) and an Airspy+Spyverter connected to a PC running SDR#
The QTH was in a large public park right in the middle of the city of Lausanne, JN36HM. By chance the QRM was not as high as I could have expected.
This RX tentative was for me a “quick and dirty” project. I built the antenna only a few days ago and have not tested it properly. Today I had no time to prepare myself in advance during the “tune” phase, and could only listen for a few minutes to the transmission at 12h45 local swiss summer time (10h45 UTC). I was very surprised to catch a visible CW signal on the waterfall display right at power on! My CW knowledge is not good enough to have decoded the transmission (read “was to fast for me!”). I got only a few letters but I am almost sure that this was the wanted signal. In the VLF band, QRM looks and hear differently than CW.
I lost the signal after maybe 1-2 minutes. I don’t know how long the transmission duration was planned. Maybe this was simply the end of the transmission.
I was unfortunately not available for the 2 other transmissions of the day.
Now that I know my setup is working, I’ll give me a chance to listen to one of the next transmissions in the coming month, from my home QTH in Neuchâtel JN36LX.
Thanks to all the team for this interesting event.
Yves / HB9DTX