L3Harris Narda SignalShark, Руководство пользователя

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SignalShark User Manual
122
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 25 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
0.5 dB. At the highest reference level setting, Atten = 2 dB; at the most sensitive
reference level, Atten = 0 dB.
It is possible to decouple the reference level and the input attenuator indirectly using the
Y-Scale Ref parameter in the Display menu.
Setting the reference level (Ref. Level)
You selected the desired view.
1.
Tap the
Ref. Level
button.
The settings dialog opens.
2. Enter the required value and tap the unit button.
The setting is accepted immediately and the dialog is closed.
Or use the Rotary knob to change the value.
Setting the attenuator value (Attenuator)
You selected the desired view.
1. Tap the Attenuator button.
The settings dialog opens.
2. Enter the required value and tap the unit button.
The setting is accepted immediately and the dialog is closed.
Or use the Rotary knob to change the value.
Selecting the RF input (Input)
To select the RF input:
1.
Tap the Input button and enter an input.
2. Tap the OK button to accept the setting.
The input window is closed.
3. Press the Esc key to close the context menu.
Lowering/rising the level by 5 dB (+5 dB / -5 dB)
1. Tap the +5 dB or -5 dB button.
2. Press the Esc key to close the context menu.
About the +5 dB / -5 dB buttons:
You can use the +5 dB / -5 dB buttons to check for over modulation and to rapidly change