[R-390] Power supply MOD
Jim Green
jagreen3 at sbcglobal.net
Sun Apr 22 18:07:17 EDT 2012
Naturally I am not the first to have worked on this R-390. I found a
MOD (Modification) in the Power Supply.
V801 is missing from it's socket. A wire is coming out of the center
hole leading to a big 30 Ohm 18 Watt wire wound ceramic resistor. The
big 30 Ohm is in the circuit between pin 6 of V801 and pin 8 of V801.
I can see no other changes. It looks like this big resistor just drops
the 285V Pin 6 voltage down to the 240V Pin 8 voltage. All the
operational pins on the V801 socket are common to the same pins on V802.
This doesn't seem like a very good idea for some reason. Can someone
give me a clue what the tech was thinking?
Jim
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