Anritsu MG369 Series, Operation Manual

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Attenuator
Decoupling In MG369XBs equipped with Option 2 step
attenuators, the ALC and attenuator work in con-
junction to provide leveled output power down to
–140 dBm. In the normal (coupled) leveling mode,
when the desired power level is set, the correct com-
bination of ALC level and attenuator setting is de-
termined by the instrument firmware. In some
applications, such as receiver sensitivity testing, it
is desirable to control the ALC level and attenuator
setting separately by decoupling the step attenuator
from the ALC. The ALC mode menu lets you select
attenuator decoupling.
At the ALC Mode menu, press Attenuation > . The
Attenuation menu (below) is displayed.
This menu lets you decouple the step attenuator
from the ALC, set the power level, and set the atten-
uation in 10 dB steps.
Press Decouple [AT1] to decouple the step attenua-
tor from the ALC.
Press Edit L1 [XL1] to open the power level parame-
ter for editing. Edit the current level using the cur-
sor control keys, rotary data knob, or enter a new
value using the key pad and appropriate termina-
tion soft-key. When you have finished setting the
power level, press
Edit L1 to close the open parame-
ter or make another menu selection.
When decoupled, pressing Increase Attenuation
[ATT(xx)] or Decrease Attenuation [ATT(xx)] changes
the attenuation in 10 dB steps.
Press Decouple again [AT0] to recouple the step
attenuator.
Press < Previous to return to the ALC Mode menu.
MG369XB OM 3-67
Local (Front Panel) Operation Leveling Operations
NOTE
The set power level may not be
maintained when switching be-
tween attenuator coupling modes.