An efficient spiker-sustainer excitation scheme wherein a single source power and a single switch controls all the three discharges viz., the pre, the spiker, and the sustainer is reported. The delay between the discharges can be controlled by the usage of a simple wire wound inductance of appropriate value. The isolation element between the spiker and the sustainer discharges, an integral part of the conventional spiker-sustainer excitation scheme, is dispensed with here. The performance of this scheme has been tested in the operation of a TEA CO₂ laser, which produced energy of 2.1 J per pulse at an operating efficiency of 18%.