TECHNICAL SUPPLEMENT FOR THE SR-160 & SR-500 by WDØGOF August 2010
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This one was rescued from the loft of a barn. Restored, striped and painted.
POWER SUPPLY NOTES
When recapping power supplies there seems to be an uncontrollable erg for most people to install a three-wire
power cord. Don’t do it.
The PS-150-120 and the PS-500 power supplies do not like three wire power cords.
The system will have a 60/120 HZ hum. A keyed 2 wire cord should be used. On the PS-150 the wide pin (the
neutral wire) of the plug will connect to C202. The narrow pin connects to the fuse. Use the same format for
the PS-500. Capacitors C201 and C202 are safety capacitors. "Line-to-ground" line filter capacitors should be
replaced with Y2 or X1/Y2 safety capacitors. (Do not use X2 type). All caps should be replaced with modern
caps not NOS parts. NOS parts were made with old methods and old materials. Modern methods and modern
materials are far superior. The only good use of NOS parts is in museum radios that will never be turned on.
