DaveM wrote:

Well, since you've already had the cover off, try this.
Open the meter again and gently try to move the needle back toward zero with a
fingertip or a toothpick. If it doesn't move freely, or moves but stays in the
position it was moved to, your meter is damaged. Most likely cause is a broken
hairspring or pivot. In either case, the meter is unrepairable by most. The
only course of action is to buy a new tester.
You can, of course, get some small tools and gingerly disassemble the meter to
get at the innards, but if the meter is damaged as I described, you're just
chasing a rainbow.

If the meter needle does move freely but just returns to mid scale, you might be
able to remedy that. Open the meter and remove the screws that hold the meter's
mechanism in the housing. You might have to fiddle with the wires that connect
the meter mechanism to the terminals on the rear of the housing. Keep them out
of the way, or at least keep the strain off those wires because they attach to a
delicate mechanism. On the rear of the movement is another pivot adjustment,
normally where one of the connecting wires is soldered. Gently move this pivot
arm and see if the needle responds. If so, see if there is enough range in
movement to return the needle to normal zero position. If so, you're home free.
If not, you're back to square one, looking for a new tester.




Before you change the rear spring setting you should inspect the spiral
springs. I have seen cases
where the spiral turns got tangled (probably by too much current). I
used a tooth pick or small
wire to untangle the loops of the spring. Also look at the pivots. If
your meter coil and pointer
are supported by a "taught band" then all of the advice I gave doesn't
apply.

Bill K7NOM