Suitcase SETI was a portable, high-resolution spectrometer, developed in 1981–82 by Harvard physicist Paul Horowitz and colleagues from Stanford University and NASA, with support from NASA and the Planetary Society, for use in SETI. It enabled the kind of signal processing used in the earlier Harvard-Arecibo search to be carried out in real-time. Suitcase SETI was capable of 64 K-channel spectrum analysis (0.03 Hz resolution bandwidth, 2 kHz instantaneous bandwidth) in each of two polarizations, equivalent to searching 131,000 extremely narrow-band channels. It was connected to the Arecibo radio telescope in Mar 1982 and used to search 250 candidate objects (stellar and other), mostly at the second harmonic (2.84 GHz) of the 21-centimeter line. Suitcase SETI was later reconfigured and used in Project Sentinel.
1. Horowitz, P. "A Search for Ultra-Narrowband Signals of Extraterrestrial Origin," Science, 201, 733 (1978).