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6.6 Setting the reference level (Reference Level)
Narda IDA - 3106
97
3.
Use the rotary control knob to select the desired setting and press the
OK
key.

The selected value is applied. The selected T-RMS is shown in the
lower status bar.
6.6 Setting the reference level
(Reference Level)
All operating modes
To set the reference level:
 Press the
Reference Level
softkey.
You can now select the reference level as follows:
•
Manual reference level selection
•
Automatic reference level search (RL Search)
Background information:
The sensitivity of the system depends on the input attenuator setting.
This setting is determined by the
Reference Level (RL)
parameter. High
measurement sensitivity avoids falsification of the results due to noise
generated internally by the device. On the other hand, it is important that
the device is not overloaded (saturated). Saturation can also be caused
by signals outside the frequency band, e.g. high power radio transmitters
when measuring mobile telephone signals.
The reference level setting covers up to 50 dB depending on the attached
components (handle, type of antenna, etc.) and is coupled to the setting
of the input attenuator (Attenuator, Atten). The input attenuator can be
matched ideally to the measurement signal by means of its fine
adjustment in steps of 1 dB. At the highest reference level setting,
Atten = 50 dB; at the most sensitive reference level, Atten = 0 dB. The
actual value of the input attenuator setting is shown in brackets after the
reference level.
It is possible to decouple the reference level and the input attenuator
indirectly using the
Y-Scale Ref
parameter in the
Display
menu.