Original poster: <sparks@xxxxxxxxxxxxxx> > However, a very clever idea. I have never seen > anyone taking the control winding out on 2 separate cores. See "Electronic Transformers and Circuits" by Reuben Lee (ed. 1955) Page 260, where the same circuit is shown. 73, Ralph W5JGV - WC2XSR/13 - WD2XSH/7 http://w5jgv.com http://500kc.com http://spectrotek.com http://kc5cah.com