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V1.0
07/01/22
Newark.com/multicomp-pro
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Reference level located at the top of axis grid. Measurement near the reference level would gain better accuracy, but input
signal amplitude should not exceed the reference level; if it exceeds, the signal will be compressed and distorted, result in
wrong measurement. Analyzer’s input attenuation is related with reference level, it can self-adjust to avoid signal
compression. Minimum reference level is -80dBm at Log scale under 0dB attenuation.
5.3.2 [Attenuation Auto Man]
Sets the front attenuator of the RF input in order to permit big signals (or small signals) to pass from the mixer with low
distortion (or low noise). It only works under internal mixer mode to adjust input attenuator insider analyzer. In Auto mode,
input attenuator is related with reference level.
Key points:
• When the preamplifier is On, the input attenuation could be set up to 40 dB. You can adjust the reference level to ensure
that the specified parameters meet the requirement.
•
Modifying the reference level may cause an automatic change in attenuation value; But the change of attenuation value
won’t influence reference level.
•
You can modify this parameter using the numeric keys, knob, or direction keys.
Attenuator adjustment is to make the maximum signal amplitude pass from mixer less than or equal to -10dBm. E.g. if the
reference level is +12dBm, the attenuator value is 22dB, then the input level in mixer is -18dBm (12-22-8=-18), its mainly
purpose is to avoid signal compression. Switch [Input Atten Auto Manual] to manual mode, adjust the attenuator manually.
The highlight under auto or manual stands for auto coupling and manual coupling. When attenuator is under manual mode,
press [Input Atten Auto Manual] will match the attenuator and reference level again.
Note:
Maximum input signal amplitude of input attenuator (10dB input attenuation at least) is +30dBm, higher power signal
will damage input attenuator or mixer.
5.3.3 [Scale/Div]
Sets the logarithmic units per vertical grid division on the display. Select 1,2,5 or 10dB log amplitude scale. It’s 10dB/div by
default. Every activated marker is with dB as unit, difference between two markers is treated as marker difference under dB
unit.
Key points:
•
By changing the scale, the displayed amplitude range is adjusted.
• The amplitude that can be displayed is from reference level minus 10 times the current scale value to the reference level.
•
You can modify this parameter using the numeric keys, knob, or direction keys.
5.3.4 [Scale Type Lin Log]
Sets the Scale Type of Y-axis to Lin or Log, the default is Log. It only works under internal mixer mode. In general, select mV
as Lin amplitude scale unit. Of course there would be other units for select.
Key points:
• In Log scale type: the Y-axis denotes the logarithmic coordinates, the value shown at top of the grid is the reference level
and the grid size is equal to the scale value. The unit of Y-axis will be automatically switched into the default “dBm” when
the scale type is changed from Lin to Log.
• In Lin scale type: the Y-axis denotes the linear coordinates, the value shown at the top of the grid is the reference level
and the bottom of the grid shows 0 V. The grid size is 10% of the Reference level and the Scale/Div is invalid. The unit of
Y-axis will be automatically switched into the default “mV” when the scale type is changed from Log to Lin.
• Other than as mentioned above, the unit of Y-axis is independent of the Scale Type.
