Toby Stensland wrote:

<snip>
> It consists only of a potentiometer (100k, to select voltage), a red disc capa
citor marked V130LA10A,<snip>

The V130LA10A is a MOV (Metal Oxide Varistor).  It is a transient voltage surge
supressor and is
usually used across an AC power line.  It has a nominal breakdown voltage of 130
 AC (RMS) or 175VDC.
It handles about 38 joules of energy.  The 10A at the end is supposed to be an a
mperage rating, but I
could never make it fit the specs.  Anyway, a 10A handles approximately half the
 current of a 20A, etc.

Michael

*************************************************************************
When the way of the Tao is forgotten, kindness and ethics must be taught.
Men must learn to pretend to be wise and good.  --  Lao Tzu
*************************************************************************