YX-1000A Meter Assembly

The meter window is 4.5 cm in height and 5.7 cm in width. The top scale in green is for measuring resistance, and the next part of the scale is supposed to be a mirrored strip, but is grey in colour, and appears white in the photograph above. There are two scales for DC voltage and current, marked in black, with 250 and 50 at full-scale deflection positions. There is one scale, marked in red for AC voltage, with 10 at the full-scale deflection position. There is also a scale in red marked dB, which usually calibrates against the AC voltage scale.

The meter dial is paper card with a nice sharp print, and legible fonts. If you have learned to use analogue meters correctly, then you will rely on the mirrored strip that is along the scale, to help eliminate parallax errors. This is an important aspect of these meters if you wish to take accurate readings. The only downside is that the strip which is supposed to be mirrored is grey coloured, because the dial is printed.

Usually meter design follows the d'Arsonval movement, or a variation of it. As you can see from this meter assembly, there is a voice coil and permanent magnet. A coil spring performs the needle return function.

This meter movement does not have any kind of damping, which means that the needle bounces around before settling on a value. This can be annoying if you were taking many measurements quickly.

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