[SENSe:]FREQuency:APERture

34980A

[SENSe:]FREQuency:APERture

Syntax

[SENSe:]FREQuency:APERture {<seconds>|MIN|MAX|DEF} [, (@<ch_list>)]

[SENSe:]FREQuency:APERture? [{(@<ch_list>)|MIN|MAX}]

Description

This command selects the aperture time (also called gate time) for frequency measurements on the specified channels. If you omit the optional <ch_list> parameter, this command applies to the internal DMM, independent of any channels or a scan list.

Used With:

  • 34921A through 34925A Multiplexer Modules

Parameters

Name

Type

Range of Values

Default Value

<seconds>

Discrete

Desired gate time in seconds:

10 ms (4½ digits, MIN)
100 ms (5
½ digits)
1 second (6
½ digits, MAX)

100 ms

<ch_list>

Numeric

One or more channels in the form (@sccc).

If <ch_list> is omitted, this command applies to the internal DMM.

Remarks

  • For the <seconds> parameter, you can substitute MIN or MAX for a numeric value. MIN selects the smallest value accepted, which gives the lowest accuracy; MAX selects the largest value accepted, which gives the highest accuracy.

  • If you omit the optional <ch_list> parameter, the configuration applies to the internal DMM, independent of any channels or a scan list (any existing scan list is not redefined). An error is generated if the internal DMM is not installed or is disabled.

  • Since frequency and period are related functions, changing a measurement parameter for one function will also change the corresponding parameter for the other function (see [SENSe:]PERiod:APERture command).

  • The instrument sets the aperture time to 100 ms after a Factory Reset (*RST command). An Instrument Preset (SYSTem:PRESet command) or Card Reset (SYSTem:CPON command) does not change the setting.

Return Format

The query command returns the aperture time in the form "+1.00000000E-01" for each channel specified. Multiple responses are separated by commas.

Examples

The following command sets the gate time to 10 ms on channels 3 and 13 in slot 1.

FREQ:APER 10E-03,(@1003,1013)

The following query returns the gate time selected on channels 3 and 13 in slot 1.

FREQ:APER? (@1003,1013)

Typical Response:  +1.00000000E-02,+1.00000000E-02

See Also

CONFigure:FREQuency