DMM acting flaky
 

I've got a Rat Shack (micronta) 22-174B that I use for my hobby, which
is building guitar effect pedals. It's a cheap unit, but it's got the
functions that I need, such as a capacitance meter, hfe, etc.
Anyhow, I can't get good ohm resistance readings at all anymore. It is
way off. And the continuity tester beeps if I hold both a lead in each
hand.
I put in fresh batteries, the internal fuses are good, etc.
Anyone has an idea?

DMM acting flaky
 

In article om,
says...
I've got a Rat Shack (micronta) 22-174B that I use for my hobby, which
is building guitar effect pedals. It's a cheap unit, but it's got the
functions that I need, such as a capacitance meter, hfe, etc.
Anyhow, I can't get good ohm resistance readings at all anymore. It is
way off. And the continuity tester beeps if I hold both a lead in each
hand.

Not very familar with the RS products, but many DMM's use
a ratiometric configuration with the reference resistor in
series with the unknown. You may have blown the reference
resistor.

DMM acting flaky
 

Peobably some of its referencing resistors are blown. Maybe someone put
aome voltage through the meter while it was in the ohms mode. You will
most likely need the service manual for the meter in order to service
it. You will also need the parts source for the meter's parts. These
resistors are generaly precision resistors. Using regular off the shelf
ones would not be accurate.

Jerry G.

DMM acting flaky
 

Thanks for the reply, I'm trying to find a schematic and parts source
for it, wouldn't you know, the Rat Shack is of little help.