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Re: SAQ 17.2 kHz QRV today
I think it would be easier and much more fun for all if I just put some recordings up, then you can spend as much time as you want going through them and identifying the signals (naval, time, navigation, grid sync, mysterious, etc.) for yourselves. I've created a Dropbox folder here: https://www.dropbox.com/sh/t1pqcqvs93vqjle/AAAMm9XIH8FyAE4Fx9kmA8wOa?dl=0 which has some more SAQ pics, a recording of the second transmission (I also have the first, if you want it), and a midday VLF recording from today, covering 10 - 200kHz. The signals you can pick up don't change much throughout the day, except that the clusters of carriers at 16, 32, 48kHz from my solar panel microinverters won't be there after sunset, but there will be a lot more storm noise instead. Thunderstorms over Europe are very active at the moment, but if they quieten down I'll do another nighttime recording for you. By chance, the LORAN transmitter about 70mi from me is down at the moment, so the spectrum between 90 and 120kHz is open, instead of being a wall of solid white (the signals visible around 110kHz are probably down to low power testing of equipment at the transmitter). There are no Russian Alpha transmissions on at present, unfortunately!
The recording today was made on an HF+ (with R3 shorted) and a Wellbrook LFL1010 loop turned E-W.
If you want to post a recording or two, I'd be very interested to see what it's like on your side of the Pond!