The Stanford VLF station on Crete



The VLF receiver was installed in Heraklion, Crete, Greece in the framework of the CAL project in collaboration with Stanford University. It started its routine operation on 18 July 2003.


Stanford VLF receiver
The VLF receiver


VLF data aquisition panel
Data aquisition is underway


Stanford VLF receiver
Close-up: HUB, GPS, receiver,
power supply, filter box

Magnetic loop antenna
The magnetic loop antenna


The Crete VLF receiver (35.1 N, 25.08 E) uses a north-south oriented 1.7m x 1.7m magnetic loop antenna. The detected wideband signal is bandpass filtered to the range of 9–45 kHz and sampled at 100 kHz with 16-bit resolution using triggers provided by GPS timing. The wideband signal is digitally down-converted into narrow bands, centred around pre-selected frequencies of VLF transmitters.

During EuroSprite 2003 the demodulated amplitude and phase time series of the narrowband signals were recorded with 20 msec resolution, from 17:00 to 05:00 UTC. The great circle paths from the transmitters to the Crete receiver used during the EuroSprite 2003 campaign to Crete (click on the image to magnify it):
Links 2003

During the Eurosprite 2005 campaign broadband VLF data was also recorded, with 100 kHz sampling frequency, from 17 to 05 UTC. Currently, narrowband data is recorded daily from 15 to 11 UTC for 14 transmitter signals (see the sketch below for the GCP-s). Broadband recordings are made synoptically.

Links 2005



[The OmniPAL VLF receiver]

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