Abstract: The invention is a radiation hardened bistable logic circuit employing two pairs of parallelly connected transistors, cross coupled through diode "OR" circuits, with back-to-back diodes between the gates or bases of the two FETs or bipolar transistors comprising each pair.

Abstract: Apparatus for providing alternating current electrical energy to a load wherein an alternating current energy source includes one or more direct current energy sources coupled to one or more inverters each having at least one switching element therein. Switching elements are controlled to provide alternating current waveforms having a relatively low harmonic content. A preferred embodiment has two alternating current sources. The two alternating current sources are coupled to the load in a manner which causes their output voltages to be summed vectorially across the load. The phase difference between the output voltages of the two sources is controlled to regulate the resultant load voltage by controlling the operation of the switching elements in the inverters.