Wild_Bill wrote in message
...
I've never needed to repair that type of meter movement, but it sounds as
though what has been described is likely to be the Taut-Band type of meter
movement.

--
Cheers,
WB
.............


"N_Cook" wrote in message
...
Anyone any experience? Coil is fine. This is almost hair-fine
phosphor-bronze ribbon suspension , not hairspring and jewels. A ribbon,
top
and bottom, holds the coil frame and passes current. Each ribbon is
soldered
to the frame then passes through a hole in the offset-rotatable anchor ,
passes over the rounded edge of an open end of a U-shape of manageable
size
phosphor bronze spring , and soldered along the arm of that spring. The
solder point to the frame has failed from a jar / knock. So both U
springs
are now opened to a V in comparison. I have tried solder to the end of
the
fine ribbon and the stub on the frame, both take solder fine but not
joined
up yet. There is enough length of fine ribbon on the broken side to
resolder
to the coil frame , pass thru the hole and anchor off , on its u-spring
anchor farther along than originally.
But how to bring the open-U springs back to proper U before soldering
the
anchor point. A matter of making a jig to compress or some sort of
external
spring over them ? And of course I've not seen a functioning movement.
I'm
assuming setting up as U and then opening out a bit with the jigs
removed,
or would the jig need to compress to more than U and then open out to U
with
jigs removed, normal use.
Pushing down on the spring of the good end and letting the coil frame
drop,
with gravity, it seems to be centrally aligned over the pole piece,
when
the spring is a proper U viewed on side.
Where would one find , even robbing, short lengths of such rbbon if it
was
required?





I never looked inside one but all those broken Pye/Cambridge? moving spot
galvanometers presumably had that system. While at it anyone know what the
suspension is in Megger insulation tester? that dead springless movement,
jewelled without hairspring? - I've never looked insiside the meter movement
of one