[Elecraft] OT: Bird Wattmeter "meter failures"

[Ken G Kopp]

An earlier posting brings this to mind ....

There is a seemingly little-known failure that frequently occurs to Bird
meter movements ... or more correctly ... to the connector at the sensor
casting end of the length of coax used to connect the (30 ua) meter to the
sensor.

Often a sharp "whack" on the housing will cause the meter to resume
working, often for long periods of time.  The connector's internal
connection is made by inserting the (solid) center conductor of the coax
between turns of the coils of a tiny spring that's part of the center pin
assembly of the casting end's cable connector.

There's such a tiny amount of current flowing through the coax center
conductor and the spring "connection" that it seems to corrode easily, and
most assume the meter movement has failed.  The resulting tiny disturbance
to the wire/spring junction is why the "slap" on the housing often brings
the meter back to life.  Many of the expensive proprietary meters have been
needlessly replaced because of this.

73 - K0PP