Keysight Technologies 8163A/B, Programming Manual

Page: 148 / 306

148 8163A/B, 8164A/B & 8166A/B Mainframes Programming Guide
4 Measurement Operations & Settings
command: [:SOURce[ n ]][:CHANnel[ m ]]:POWer:ATTenuation[ l ]:DARK?
syntax: [:SOURce[ n ]][:CHANnel[ m ]]:POWer:ATTenuation[ l ]:DARK?
description: Queries whether the attenuator is set to ‘dark’ position (where all light is blocked by the laser).
parameters: none
response: 0:
1: dark position not set
dark position set
example: sour0:pow:att:dark? -> 1<END>
affects: All tunable laser modules with a built-in optical attenuator.
command: [:SOURce[ n ]][:CHANnel[ m ]]:POWer[:LEVel][:IMMediate][:AMPLitude[ l ]]
syntax: [:SOURce[ n ]][:CHANnel[ m ]]:POWer[:LEVel][:IMMediate][:AMPLitude[ l ]]<wsp><value>
[PW|NW|UW|MW|Watt|DBM]
description: Sets the power of the laser output.
If an optical attenuator is installed, the power value returned is dependent on whether you are using power or attenuation
mode (see
[:SOURce[n]][:CHANnel[m]]:POWer:ATTenuation[l]:AUTO
on page 146).
If you are using power mode, the value returned is the output power.
If you are using attenuation mode, the value returned is the laser output power, and you must also use the attenuation value
to calculate the output power (see
[:SOURce[n]][:CHANnel[m]]:POWer:ATTenuation[l]
on page 145).
The values for the output power that you set in the Power Mode, and the laser output power that you set in the Attenuation
Mode, are stored and used independently.
The instrument may not be able to output a signal with the maximum programmable power, it will output a signal with the
maximum power. Use the
[:SOURce[n]][:CHANnel[m]]:POWer[:LEVel][:IMMediate][:AMPLitude[l]]?
on page 149 to query the power being output.
The default units are
DBM
or
W
, depending on the unit selected using the following command:
[:SOURce[n]][:CHANnel[m]]:POWer:UNIT
on page 151.
parameters: Any value in the specified range (see the appropriate User’s Guide ).
Also allowed are: MIN: minimum programmable value
MAX: maximum programmable value
DEF: This is not the preset (*RST) default value, but is the maximum programmable level
Use [ l ] to set the amplitude level of the output power of the upper or lower wavelength laser source of a dual-wavelength
laser source or a return loss module with an internal dual-wavelength laser source. The default value of [ l ] is 1 , the lower
wavelength source. The upper wavelength source is denoted by 2 .
response: none
example: sour2:pow 23uW
affects: All tunable laser including 81950A and DFB source modules