The Very Small Array

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The Very Small Array Project: VSA PI: Dr. H. Paul Shuch, Exec. Dir., The SETI League, Inc. ([email protected]) Description and Objectives: A test platform for future research-grade radio telescopes, the Very Small Array is a low-cost effort to combine the collecting area of multiple off-the-shelf backyard satellite TV dishes into a highly capable L-band observing instrument. A volunteer effort of the grassroots nonprofit SETI League, the VSA is being built in the Principal Investigator’s backyard, with member donations and modest grant funding. A US patent has been issued for our technique of employing combined analog and digital circuitry for simultaneous total power radiometry, spectroscopy, and aperture synthesis interferometry. Key Features of Instrument: Schedule Milestones: Phase 0: Paper design, single-dish test bed; § 8 ea. 1.8 meter reflectors in Mills Cross array US patent #6,593,876 (issued 2003) § Offset feeds for non-blocked aperture Phase 1: Physical Structures – (completed 2004) (masts, az/el mounts, dishes, feeds, § Meridian transit mode w/ elevation rotation conduit, junction boxes cables) § Dual Orthogonal Circular Polarizations Phase 2: Front-end electronics (in process 2005) Phase 3: Back-end electronics + DSP (planned for 2007) § Full ‘water-hole’ coverage, 1.2 – 1.7 GHz Applications: § Simultaneous total power radiometry, spec- § Meridian transit all-sky SETI survey troscopy, and interferometry in real time § Parasitic Astrophysical Survey § Targeted SETI in direction of known exoplanets Partners: § Quick-response verification of candidate SETI signals American Astronomical Society, ARRL TRL = 3 Foundation, Microcomm Consulting Revised: 12 May 2005 Keywords: Radio Telescope, Phased Array, Mills Cross, Radiometry, Spectroscopy, Interferometry, SETI.

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Radio and Millimeter Continuum Surveys and Their Astrophysical Implications
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