Channel A
Sensitivity adjustment
Channel A (and thereby also Channel C, as it shares the same
input) has an adjustment control which allows lowering the
input's sensitivity.
This may be necessary if the input signal is noisy or is
superimposed by another signal that has a greater amplitude
than the sensitivity of the input.
The input has a hysteresis of about 10 mV, so noise lower than
this has no effect. However, increased immunity to noise
always lowers the sensitivity for small useful signals, so a
compromise has to be made here. In addition, it is required that
the adjustment of the input amplifier has been done accurately
(see the appropriate chapter for details).
In the first example on the next page, the superimposed
sawtooth wave would lead to false counts, if the sensitivity
were set to max, since its amplitude is greater than the
hysteresis.
If the sensitivity is lowered, this signal is below the threshold
and ignored, while the sine wave is measured.
The second example shows the same behavior with one signal
superimposed on another, when only the fundamental should
be measured.
30
Summary of Contents for AE20401
Page 23: ...Finished Component Side Finished Solder Side without the LCD LCD Mounting 17 ...
Page 31: ...Operation Functions Menu Structure 25 ...
Page 37: ...31 Example 1 noise Example 2 one signal superimposed on another ...
Page 50: ...Circuit Diagram Part 1 2 44 ...
Page 51: ...Part 2 2 45 ...
Page 63: ... Nr of valid counts depends on range 57 ...
Page 64: ...ASCEL ELECTRONIC www ascel electronic de 2015 ...