homemade ballasts

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Gregory Peters by way of Terry Fritz <twftesla-at-qwest-dot-net>" <s371034-at-student.uq.edu.au>

Hello all,

I have currently been using two welders in parallel to ballast my 
PDT. However, two welders isn't exactly space efficient, so I would 
like to make my own ballast using either an EI core or tube full of 
metal rods. Is there any reason why I can't use stranded pvc 
insulated wire for this purpose? Everyone seems to use solid core 
THHN wire. Firstly, what the heck is THHN? I can't find any reference 
to this type of wire in any Australian catalogues. In any case, other 
than magnet wire, I can't find any solid core wire that is thick 
enough to handle ~50 amps.

Cheers,

Greg.