Ultra Low Frequency Observatory (ULFO)
Very Low Frequency Observatory (VLFO)
Live data from NORTHERN CROSS RADIOTELESCOPE
Medicina (Bologna) Maintained by Jader Monari

Google map click here http://goo.gl/maps/kYQRK (Lat. 44°31'27.70"N - Long. 11° 38'41.97"E)




The ULFO receiver (Ultra Low Frequency Observatory) is a ultra low frequency receiver (0.1Hz-35Hz) installed near Medicina (BO) close to the Northern Cross Radiotelescope (INAF institute).
The project started by the work followed respectively by Andrea Ghedi and Carla Cirolli has been supervised by Jader Monari during their thesis.
The system now is working by the support of ICPH and Renato Romero, and all the data are available.
The preliminary high sensitive lock-in receiver developed inside the INAF laboratory has been replaced with  a low noise amplifier ICS101 in order to simplify the design of the entire system and getting used of ULF reception.

A short article about the work of  Andrea Ghedi and Carla Cirolli can be found ICPH
Instead a description of the Renato Romero's receiver ICS101


ULFO: INDUCTION COIL

The induction coil is made by a silicon iron (FeSi4 μr = 4500) composite core of 75 mm diameter,  where has wound a enamelled copper wire 0.5 mm. a. The total length is 17 km for  100000 turns and the weight of the coil  is 35 Kg



Induction coil
 ICS101 preamplifier

ULF MAGNETIC FIELD
Here the live spectrogram, updated every 15 minutes. It shows the last 8 hours ULF activity,
from 0.1 to 35Hz.
    

Bottom part zooms on the 0.1 to 4 Hz range. FFT resolution 21 mHz, scroll time 40 seconds.


Spectrogram in 1 hour strips, from 0.1 to 35 Hz. Picture updated every 15 minutes.
  

   
FFT resolution 84 mHz, scroll time 4.6 seconds.

 
Multistreap spectrogram in 1 day strips, from 0.1 to 10 Hz. Picture updated every 15 minutes.
   

   
FFT resolution 21 mHz, scroll time 109 seconds.



Five days monitoring interaction in the same spectrogram, from 0.1 to 35 Hz.
FFT resolution 42 mHz, scroll time 8.35 minutes.


ELF-VLF ELECTRIC FIELD



 VLF receiver with 8 meter T antenna
 		 LNVA 24-20 VLF receiver


Last 8 hours ULF activity, from 0.1 to 100Hz. Picture updated every 15 minutes.
    

FFT resolution 21 mHz, scroll time 40 seconds.


Spectrogram in 1 hour strips, from 0.1 to 100 Hz. Picture updated every 15 minutes.
  

   
FFT resolution 84 mHz, scroll time 4.6 seconds.

 
Multistreap spectrogram in 1 day strips, from 0.1 to 100 Hz. Picture updated every 15 minutes.
   

   
FFT resolution 21 mHz, scroll time 109 seconds.



Five days monitoring interaction in the same spectrogram, from 0.1 to 100 Hz.


FFT resolution 10 mHz, scroll time 8.35 minutes.



Last 8 hours VLF activity, from 100 to 22000Hz. Picture updated every 15 minutes.
FFT resolution 732 mHz, scroll time 40 seconds.



Here below the real time situation about lighting strikes in Europe.
Courtesy of http://www.blitzortung.org/

Unattended operations, signal conditioning, spectrograms and RDF functions are performed with
SpectrumLab: http://www.qsl.net/dl4yhf/spectra1.html .
Many thanks to Wolfgang Buscher for his support.
Automatic FTP process is realized with Dropbox https://www.dropbox.com/


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