Is it possible to make an #antenna for the difficult #VLF frequency band, where the resonant dipole length is usually much longer than the available space for a VLF antenna, in which the absorption of the desired signal is assisted by nuclear magnetic resonance?

That sounds very goofy perhaps, but it occurred to me that this is one of the very few physical processes I can think of whose RF absorption maximum can be tuned down to kHz frequencies by using a sufficiently small external magnetic field and a nucleus with a low magnetogyric ratio.

Due to the initial antenna connection problem, I missed the tuning-up, but most of today's SAQ is here. A strong, ~S7 signal today, with a clear signal from the carrier during key-up times.

Frequency control was excellent today, well within the design +/-10Hz. Given it's an electromechanically-regulated spinning metal disc, this is always pretty amazing!

https://youtu.be/E-qUdiLyUoA?si=Fy-s_2eXOdnR8-EB

#VLF #wireless #radio #heritage

24 December 2025: The Very Low Frequency (VLF) transmitter from Grimeton (Sweden) with the call sign SAQ goes on air. Is it possible to receive this transmitter with simple means in the city of Bern? Yes, it is possible.
Antenna: (DIY) three ferrite rods wound with HF litz wire.
DIY up-converter.
Degen DE1103 receiver.
The signal was weak, but it was still possible to copy it.

#SAQ #Grimeton #VLF #SWLing #CW #Morse

Cold War VLF and a Bob’s Homemade “LWL” QSL Card

https://swling.com/blog/2025/12/cold-war-vlf-and-a-bobs-homemade-lwl-qsl-card/

#BobK7ZB #LWLQSL #QSLCards #VLF

Tonight I'll play a new work, Radio Strata in Esc Gallery - Graz.

It is a journey in radio recordings I've made, from cosmic sources towards Earth, passing through satellites.

Come for the ending of the "Out of Control" exhibition! More infos here:

https://esc.mur.at/en/projekt/out-control

(Big thx to @reni )

#radioart #vlf #meteor #soundart