  In the present manuscript we consider the possibility of SETI by the small
size (with diameters less than 1 m) optical telescopes. Calculations are
performed for typical parameters of the mentioned type of telescopes. In
particular, we show that the techno-signatures of Type-2.x and Type-3.x
civilizations might be detected. It is demonstrated that it is possible to
detect as hot megastructures (up to 4000 K) built around main sequence stars
and pulsars as well as von Neumann extraterrestrial probes.
