  The dark rate of single-electrons emitted from a cathode of a multi-cathode
counter may be interpreted as the effect from Hidden Photons (HPs) of Cold Dark
Matter (CDM). As a tentative approach the measurements have been performed at
different temperatures of the counter. Preliminary results of measurements by
using a counter with a copper cathode are presented. An upper limit of
4.3x10-23 for parameter ksi^2 at 2 sigma has been obtained for hypothetical
conversion of hidden photon to real photon at the metallic surface with the
resulting emission of single electron. The work is considered as a pure
illustration of the method and the perspectives are discussed for future search
of HPs by a multi-cathode counter.
