On Fri, 30 Nov 2012 17:10:41 +1100, Franc Zabkar
put finger to keyboard and composed:

I'm wondering if there may be a series capacitor whose function it is
to losslessly reduce the supply voltage ...

C2
bridge 1uF
rectifier 250VAC
______ | | Vin
AC1 o--|~ +|----| |----o-- R --+----+---o Vout
| | | | | |
||| | ZD1 C
| | | |
AC2 o--|~ -|-----------o-------+----+---o
|----| 0V


Sorry, C2 should be on the AC side of the bridge, not the DC side.

- Franc Zabkar
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