The only drawback with this circuit is that it might latch in the conducting state if the load is too heavy or if there is a short at the output, this requires some kind of protection, on the input line, in the form of a fuse or similar. The transformer used is a 10W mains type with 6V+6V windings on the SCR side and a 110V+110V windings, in series, at the output. Efficiency is 50% and the ideal load is equivalent to a 22k resistor, 5W. The output waveform is vaguely sinusoidal at a frequency of 400Hz.
