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CALLISTO. C ompound A stronomical L ow frequency L ow cost I nstrument for S pectroscopy and T ransportable O bservatory. Double - Heterodyne - Frequency Agile - Radio - Spectrometer. EuroSETI Symposium Heppenheim March 26…28th 2004 Christian Monstein ETH Zürich. Directory.
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CALLISTO Compound Astronomical Low frequency Low cost Instrument for Spectroscopy and Transportable Observatory Double - Heterodyne - Frequency Agile - Radio - Spectrometer EuroSETI Symposium Heppenheim March 26…28th 2004 Christian Monstein ETH Zürich
Directory • Instrument comparison • Usage sites • Basic schematic diagram • Focal plane unit FPU • Double heterodyne receiver • Receiver control unit RCU • First solar radio noise • Overall bandwidth • Overall dynamic range • Philips tuner noise figure • Allen variance, measuring rate • First results • Field test at HB9XM`s QTH • Team members • Material costs & production time • URL`s
Instrument comparison Parameter ARGOS PHOENIX-2CALLISTO Receivertype FFTFrequency agileFrequency agile Frequency range 1290-1570 MHz100-4000 MHz47-862 MHz Obs.-bandwidth 250 MHz3900 MHz815 MHz Resolution (FD) 250 MHz {i}1, 3, 10 MHz65 KHz Resolution (TD) > 66 msec500 µs...1sec {i}2 msec Polarization linear (vertical)L, R, I, VL, R, I, V Sampletime/pixel 2 nsec0.5 msec2 msec Channels 1...50`0001...2`0001...13`120 [500] System temp. 250/530 K {iii}950 K TBD RMS noise 300/800 Jansky1000 JanskyTBD Dynamic range ~ 50 dB> 40 dB> 50 dB {i} depending on number of channels {iii} without/including calibration unit
Usage sites 5m antenna Bleien 300 MHz - 3 GHz + 80 cm-SAT 10 GHz - 12 GHz 5m antenna Zürich 1 GHz-2.6 GHz (system tests only) Planned: Green Bank Observatory West Virginia 7m antenna Bleien 100 MHz - 4 GHz
Antenna feed (s) Basic schematic diagram FPU focal plane unit Low noise preamplifiers Optional: calibration unit Twin channel receiver for two polarizations Callisto-frame Synthesizer Tuner 1 I2C-bus Down converter 37,7MHz 10,7MHz Logarithmic Detector 1 Synthesizer Tuner 2 I2C-bus Down converter 37,7MHz 10,7MHz Logarithmic Detector 2 Optional: FPU controller + Power- supply Standard PC Control+ data Integration units (low pass filters) Data aquisition unit Drivers, Buffers I2C-interfacing PSU Power source FPU control out Control path Signal path Control- data link Callisto/Host-controller Frequencyrange: 45MHz...870MHz Frequency resolution: 62,5KHz Bandwidth: ~300KHz
Focal plane unit FPU Relay-switch SPDT K1...K7 K1 A1 A1 1 2 K3 2 To 90°-Hybrid 1 Preamp Rf out-L Left Isol -10dB K6 K7 K5 1 1 1 -3dB Noise Source 2 ENR=35dB 2 2 1 Right Inp Preamp Rf out-R To 2 K4 2 Main features: + dual feed (circular L and R no linear) + very low noise + low cost + 3 point calibration - reduced bandwidth due to 1 hybrid A2 1 K2 Power supply: +15V, +28V, +5V, -15V Surveillance electronics Peltier cooler/heater Humidity/thermal sensors
First solar radio noise 5m parabola at Bleien observatory With linear vertically polarized feed HL-040 Rohde&Schwarz 400MHz…3GHz Sun is 500mV ~ 10dB ‘hotter’ than background level.
Overall bandwidth at 150.000MHz BW( -3dB) = 299KHz, BW(-10dB) = 378KHz
Overall dynamic range Detector = AD8307; dynamic range > 50dB
Callisto as a backend Callisto as a backend to a commercial S-band LNB Callisto as a backend to a commercial Ku-band LNB misused as an X-band downconverter
First results #1 Short, intensive event Long, intensive event Sun passage on 7m T0 applied +22dB ENR applied +32dB ENR applied
Fieldtest at HB9XM`s QTH `Passage` through the sun in azimuth Note the counter balance (petrol can) on the left side of antenna/FPU
Team members Responsible budget & requirements Prof. Arnold Benz Mechanical design & manufacturing Frieder Aebersold Software RISC processor (C) Hansueli Meyer Software preprocessing (C++) Christian Monstein Software postprocessing (Pearl/IDL) Peter Messmer Manufacturing focal plane unit FPU Pascal Behm Manufacturing receiver RX Pascal Behm Manufacturing receiver control unit RCU Pascal Behm Conceptual & hardware design Christian Monstein
Material costs & production time Don’t forget an appropriate antenna, a focal plane unit, a power supply and some cables
Callisto related URL`s • http://www.astro.phys.ethz.ch/rapp/ • http://www.astro.phys.ethz.ch/instrument/callisto/callisto_nf.html ETH Astronomical Institute Christian Monstein Scheuchzerstrasse 7 CH-8092 Zürich monstein@astro.phys.ethz.ch