If you are willing to try to undertake the repair yourself, see MR
November, 1955 page 32 for a good step by step procedure. The author
is John Page. HTH. I hope this message won't appear twice, but, an
earlier posting seems to be floating somewhere in cyberspace. Thank
If you can't get hold of this issue, what he basically did was smoke-
the driver to locate the shorted insulation. This was a literal smoke-
briefly done, with a big old tinplate transformer. Then he drilled
the ends of
the bad insulation with a thin drill, raked out the bad stuff with a
saw blade, and filled the gap with thick shellac. Nowadays you could
use epoxy, but the epoxy mines hadn't opened back then.
The type of short repaired was in tire-insulated drivers. Other types
insulation would require different repairs.
President, a legless table.