Steve,
WELCOME to ham radio!
Sticking meters usually have picked up a metal chip or dirt in between
the moving pivoted coil and needle and the magnet core that surrounds
the moving parts.
It could also be dirt in the needle bearing pivot points.
Use a strong light, like a bright LED flashlight, or Halogen light to
inspect the area between the moving coil/pointer and the core.
You may be able to blow out obvious dust and cobwebs with a camera
squeeze brush/ rubber bulb device, with gently puffs.
Or you may be able to take a sheet of printer paper, very smooth type
and cut a ribbon of that to pass into the space between the coil and
magnet core. But, first try to figure out what is binding the pointer.
You can puff gently with your breath to drive the pointer up scale off
rest point, and see if it only hangs up as it passes one spot.
If you have a piece of metal or chip in the core of the magnet, you have
to use the corner of a strip of printer paper to nudge it out.
Only use tweezers when you can get at it on the outer magnet area, NOT
close to the fragile coil.
To do all this, you need to have the meter out of the rig, where you can
rotate it around in your hands. Use photo cloth thin gloves to keep
sweat and skin cells off the interior of the meter. Some meter cases
are glued if plastic, others have screws and the plastic can be removed
to gain access.
The ideal meters to work on are the old round ones in metal cans where
you can get the whole meter guts out with removal of three screws around
the can.
Hopefully, you can get into the meter and puff or blow out the foreign
debris. Don't try an air hose nozzle! It will destroy the meter.
If it is a very well glued plastic cased meter, you may have to find a
similar meter to replace it, or one from a junked rig of the same model.
73,
Stuart Rohre
K5KVH
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