User`s manual

fundamental/s. When Linearity is selected dBV or Volts will be used as Y Unit. If
the compute linearity button is pressed dB or V/V are used.
Sweep Settings
These are all settings affecting the next measure to be performed. Must be
therefore handled with care.
Start and Stop
Sets the voltage sweep range supplied to the DUT input. Start should be lower
in value than Stop. While these values can be chosen in an iterative way, having
a rough idea of the DUT gain is a good practice. Notice however that keeping the
DistLim parameter to or lower than 10% would prevent hard overload of the
DUT. Sweep range stops anyway when the maximum allowed distortion is
reached, whatever Stop value is chosen. Stop value cannot be grater than 3V,
being this the CLIO’s limit.
Step
Sets sweep resolution in logarithmic equal step.
DistLim
Sets, in percentage, the maximum allowed distortion before the sweep stop
anyway.
Imp
In Ohm, displays the impedance used by the system to calculate power (use
CLIO Options>Units Conversion to set, see 5.4.2). Should obviously be set to
the real impedance that loads the DUT. Changing this value after the
measurement has no effect on an already done measure; the value should be
correct before the measure is taken.
Att
Sets the value of an eventually used passive attenuator placed on CLIO’s input.
CLIO’s input accept up to 100VRMS, that is 1250W/8Ohm. Should you need
more, use a resistors divider on the input and set the Att value accordingly.
Advised value are 90-10 Ohm to divide by 10.
Analysis
Through this radio button control the analysis type is selected.
Linearity
Measures the output Voltage Vs input Voltage. Output level is measured through
FFT looking only at the amplitude of the generated tone. That is harmonics noise
or other is not considered in the output level.
THD
Measures Total Harmonic Distortion. Again distortion level is calculated via FFT
and therefore noise is not taken in account. These, in some limited cases, at
lower level, yields to slightly different results than those obtained via traditional
THD+noise measurements. This approach is, however, more accurate. For
setting the measurement frequency please see below.
SMPTE
Measures Intermodulation distortion using SMPTE standard. Two tones are
generated in a 4:1 ratio at 60Hz and 7000Hz. Intermodulation components up to
the 5
th
order are considered for distortion.
14 LINEARITY & DISTORTION 199