An experimental investigation was made of the influence of the replacement of the working mixture and of the mixture composition on the output characteristics of a pulse-periodic electric-discharge chemical DF laser. The laser had an open gas-flow channel and its operation was based on chain and nonchain reactions. The investigation was carried out at pulse repetition frequencies from 10 to 50 Hz.

A multichannel system for determining the time parameters of pulsed laser radiation, based on a fast streak camera with fibre-optic communication lines, is described. It is shown that the tautochronism of laser beams can be determined simultaneously in all the channels of the facility and the maximum error does not exceed 25 ps.