* Ball bearing mounted shaft
* Gear drive vernier
* 1/4" flatted shaft
* Body is 1-1/4" high x 1-1/8" wide by 1-7/8" long.
* 15 plate section @ 200 pf with trimmer
* 5 plate section @ 30 pf with trimmer
* 13 plate section @ 85 pf with trimmer
* 5 plate section @ 25 pf (no trimmer)

They're priced right ($6 each), but I'm brand new to this, so I want to
verify that I can use these. The schematic calls for a 30pF cap. For
multi-section caps like these, are the sections isolated from each other
to effectively be their own component?

Typically they have one set of plates in common (usually the ones
attached to the rotating stator). Each section has a second set of
plates, insulated from the frame and from the other sections.

In other words, can I just hook up
the 30pF 5-plate section and leave the rest alone?

Yes - use the (common) stator connection, and the connection
for that one section's isolated plates. There may be a very small
amount of parasitic capacitance between the section you're using and
other sections - it's probably not enough to matter in any way.

(And for future
reference, could I hook multiple sections in parallel to create additional
capacity possibilities?)

Yes.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
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