DL0AO VLF-Grabber near Amberg, JN59VK

Antenna comparison: Two 150 m long earth dipoles (underground loops): EW = east-west 265°, NS = north-south 355°, and V = active E-field probe
(updated 2017-12-01)


Colour-DF with the two earth loops (180° ambiguous)


Alpha Colour-DF, 3.9 Hz FFT, two 3.6 s cycles every half hour (green: Krasnodar, red: Novosibirsk, purple: Khabarovsk)


VLF wideband, 1.95 Hz FFT resolution, 2 minute scrolling, upload every 10 minutes (noise blanker and autonotch disabled)
Top: EW, middle: NS, bottom: Vertical


Opposite cardioids (top: west, bottom: east)


17.47 kHz "QRSS-60", 22.8 mHz FFT resolution, 10 second scroll (W cardioid)


17.47 kHz phase-colour spectrogram, 424 µHz FFT resolution, 10 minute scroll (W cardioid)


17.4701 kHz amplitude and phase plot





8.27 and 5.17 kHz, 424 µHz FFT resolution, 10 minute scroll (top: EW, 2nd: NS, 3rd: V omni, bottom: W cardioid)



8.27 kHz, 20.93 µHz FFT resolution, 2 hour scroll, EbNaut data export 13.23 h (top: W cardioid, bottom: NW / SE)



5.17 kHz, 20.93 µHz FFT resolution, 2 hour scroll, EbNaut data export 13.23 h (top: W cardioid, bottom: EW)


970 Hz, 424 µHz FFT, 10 minute scroll (top: EW earth loop, bottom: E-field)


ZEVS phase vs GPS (retarding R-B-G-R, carrier frequency seems to be 0.11 ppm below 82 Hz), 424 uHz FFT, 10 minute scroll (E-field)


Snapshot of opposite cardioid patterns (top: west 265°, bottom: east 85°)


European lightning map from Blitzortung.org

VLF grabbers:   DF6NM   DK7FC (tree)   Paul Nicholson   IK1QFK   SQ5BPF