In a message dated 10/28/2012 7:54:31 P.M. Eastern Daylight Time, jcbyrnes at yahoo.com writes: can I substitute 650 Volt rated capacitors (assuming the same capcitance) Yes but don't use old NOS caps. Invest in fresh ones, at least for filters in the power supply and preferably any other electrolytic caps. 73, John, W4AWM