maandag 27 december 2021

SAQ Grimeton Christmas Eve transmission 2021

Radiostation SAQ Grimeton

Operator Kai in action
SAQ spreads Christmas Joy on Christmas Eve morning, Dec 24th.

During last week I carefully build up my VLF antenna to listen to the Christmas Eve morning transmission of SAQ. This Swedish station was built in Grimeton, just less than 100 years ago, to send telegrams from Sweden to the U.S. on a frequency of 17.2 kHz

My Antenna
The antenna is a loop with a diameter of 1.75 meter. The loop is tuned to 17.2 kHz to receive the signals of SAQ. The loop is connected to an amplifier with feedback to pick up the signal. First I check the antenna by increasing the feedback of the loop amplifier to make the antenna oscillate. After the check I reduce the feedback.

FT-817 + converter
The signal of the loop amplifier is fed into a frequency converter with a SO42P mixer, with a 8 MHz crystal. The signal goes to the FT-817, which is tuned to 8017.2 kHz. To check the complete setup I use an Audio signal generator set to 17.2 kHz. When I can receive this signal, I know everything is all right. 

Excellent reception
When I switched on my RIG on 7:47 utc on Christmas Eve, I immediately heard the signal of SAQ.
So the tuning with use of the Audio Signal Generator was perfect. Hi.
At the right of the loop amplifier and the converter, I had enough room to put my A4 paper to write down the message of SAQ.
I did not copy all letters, though the signal was very good, but had fun in writing down the CW message.

42 wavelengths 
The wavelength of the signal is 17,4 km, so over a distance of 736 km from Grimeton to my QTH there is room for just 42 wavelengths of the signal. Hi.