The laser-produced permanent electrical conductivity of the modified PATAC, poly(bis-alkylthioacetylene), lies between 10^-5 and 200 S/cm depending on the sample preparation and the laser irradiation conditions. The electrical conductivity of the modified PATAC is longtime stable without any special protection. The converted polymers are p-type semiconductors. The Hall mobility has been estimated between 0.01 to 10 cm²/Vs. The temperature coefficient of the resistance in the highly conducting state is low and lies between 10^-3 and 10^-4 K^-1. ESR in the 2-mm and 3-cm wavebands was applied for the study of the spin dynamics, the rate of the quasi-one-dimensional intrachain charge carriers motion and of the threedimensional interchain hopping. Depending on the conditions of the conversion and the applied temperature the conducting polymer shows typical properties of a semiconductor as well as of a metal.