Satisfactory performance of a TEA CO₂ laser of active length 30 cm is reported when self-switched by its own preioniser comprising two mutually coupled parallel spark channels or even one spark channel. A comparison of the performance of the laser with respect to the maximum extractable energy and electro-optic efficiency as a function of number of preionising spark channels is presented. With reduced number of mutually coupled parallel spark channels, the operation approaches the near ballast-free regime, resulting thereby, in an improved performance of the laser.