Vu-meter CA-3000

[Sargi]

Dear ,
I would like to know if anyone knows the full scale of the vu-meter ca3000 ?
I have the sx vu-meter open....

many thanks

 

[DougBrewster]

I presume you wish to know the magnitude of the signal required to cause full scale deflection of the meter? To calculate that we would need to know the coil resistance. In the absence of that value I can only estimate/guess that full scale deflection would require around 300 micro amps/200mV. If you need to know accurately what the FSD is you could rig up a small battery supply in series with a significant resistance and a potentiometer and measure it with a couple of multimeters.

Edit: don't try to measure that coil resistance with an ohm meter; they produce too much voltage/current which would likely damage the meter.

 

[JOMARK911]

Its a miliamperes meter.
With a standard 3aaa batteries it goes full scale . It only needs about 0,77 volts to operate .

 

[Sargi]

This morning i measure the full scale with battery 3v and 4k7 series potentiometer : 1,38 mA