EXFO FVA-3150 Variable Attenuator - Manual (Page 44)

Operating Your Variable Attenuator
38 FVA-3150
Performing an Attenuation Routine
Performing an Attenuation Routine
You can program the FVA-3150 Variable Attenuator to perform an
attenuation routine. Once the routine is started, the variable attenuator will
automatically increase or decrease the inserted attenuation (by steps),
return to the initial attenuation state, and perform the routine again until
you stop it. The following parameters may be set:

delay: the beginning of the attenuation routine may be delayed by up to
999 hours, 59 minutes and 59 seconds

duration: the variable attenuator can remain up to 999 hours,
59 minutes and 59 seconds at each attenuation step

number of steps: the attenuation routine may comprise up to 99 steps

attenuation difference between two steps: the difference in
attenuation between two steps may be up to 99.999 dB
Note: Once set, the routine parameters remain in memory until new ones are
entered.
The following example shows how parameters are set up, as well as how
an attenuation routine works.
If you start an attenuation routine with the following settings:

Delay: 5 minutes

Duration: 10 seconds

Number of steps: 3

Attenuation difference between each step: –1 dB, and

Initial attenuation state: –10 dB
the Variable Attenuator will:

Wait five minutes before starting the routine

Remain at –10 dB attenuation for 10 seconds (step 0)