Nordic Breeds WA4VZQ wrote:
"Jim Lux" wrote in message
...
Copper sulfate in water makes a nice resistor, too. It's used a lot for
"energy dump" resistors in pulse power applications.
From a theoretical standpoint, copper sulfate solutions should increase
their resistance with frequency more rapidly than the sodium and ammonium
chloride solutions used in the ARRL article. This is mainly due to ion
mobiity in solutions.
Copper sulfate is popular because it is compatible with copper
electrodes, too. Sodium chloride tends to corrode the electrodes.
There might also be some difference in solubility, which would affect
the range of resistances available.
http://home.earthlink.net/~jimlux/hv/rwater.htm has a discussion of
building water resistors for HV applications.