I picked a cheap SW-4A that had a messed up PTO. There appears to be
a spring loaded plunger that forms a 'dial stop' as it drops into a
hole on the brass gear. If the pin in the tuning shaft was little
longer, this would stop it. Is that the way it is suppose to be?

I found several websites that show rebuilding of the PTO, one says
"the worst thing you can do is turn past the stop," but haven't found
one that answers this question.

TIA,

Steve.
--
Steven D. Swift, , http://www.novatech-instr.com
NOVATECH INSTRUMENTS, INC. P.O. Box 55997
206.301.8986, fax 206.363.4367 Seattle, Washington 98155 USA