Compact Astronomical Low-cost Low-frequency Instrument for Spectroscopy in Transportable Observatories (CALLISTO)

The CALLISTO spectrometer is a heterodyne receiver build by ETH Zürich Radio and Plasma Physics Group. It operates between 45 and 870 MHz using a modern, commercially available broadband cable-TV tuners having frequency resolution of 62.5 KHz.

The data obtained from CALLISTO are FIT-files with up to 400 frequencies per sweep. The data are transferred via a R232 cable to a computer and saved locally. Time resolution is in the order of 0.25 sec, depending on the number of channels. The integration time is 1 msec and the radiometric bandwidth is about 300 KHz. The overall dynamic range is larger than 50 dB. For convenient data handling several IDL routines were written.

Several of the CALLISTO instruments have already been deployed, including 2 spectrometers in India (Ooty and Gauridbianur), in Badary near Irkutsk, Russian Federation, South Korea, Australia, Hawaii, Mexico, Costa Rica, Brazil, Mauritius, Ireland, Czech Republic, Mongolia, Germany and Belgium. Through the IHY/UNBSSI instrument deployment program, CALLISTO is able to continuously cover the solar radio spectrum from 45 to 870 MHz.

CALLISTO home page
CALLISTO general documents (click here) (The Project, Status Reports, Papers, talks and studies)

(1) Nicola Nosengo Global solar observatory flares into life. Home-built e-CALLISTO network provides real-time data on Sun's radio emissions. Nature, Published online 17 February 2011, DOI:10.1038/news.2011.97