Ivan Makarov wrote:
Thanks, Roy,

and multiturn conductive plastic/cermet pots still have the same flat
element, say , 340 degree, but incude a vernier dial that changes turns
ratio?

I've seen pots of both types, but I think the only ones I've seen with a
multi-turn helical element were wirewound. I'd say look at the shape of
the pot -- if it's a flattened cylinder like a conventional pot, it's
probably got a single flat element. On ones I have like that, the
planetary vernier drive is obvious. But if it's shaped more like a tin
can, I'd suspect a multi-turn element.

Roy Lewallen, W7EL