Specifies whether the RF IN connector is AC- or DC-coupled on the downconverter.

Syntax

RFMXINSTR_ATTR_CHANNEL_COUPLING

Numeric Value

Data Type

Access

Applies To

11

int32

Read/Write

N/A

Remarks

Name (value)

Description

-

NoteFor the PXIe-5665/5668, this attribute must be set to AC Coupled when the DC block is present, and set to DC Coupled when the DC block is not present to ensure device specifications are met and proper calibration data is used. For more information about removing or attaching the DC block, refer to the PXIe-5665 Theory of Operation or the PXIe-5668 Theory of Operation topics in the NI RF Vector Signal Analyzers Help.

You do not need to use a selector string if you want to configure this attribute for all signal instances. Specify the signal name in the selector string if you want to configure or read that signal instance. Refer to the Selector String topic for information about the string syntax.

The default value is AC Coupled.

Valid values

  • PXIe-5665 (3.6 GHz): AC Coupled DC Coupled

  • PXIe-5665 (14 GHz): AC Coupled, DC Coupled

  • PXIe-5668: AC Coupled

Supported devices: PXIe-5665/5668

Name

Value

Description

RFMXINSTR_VAL_CHANNEL_COUPLING_AC_COUPLED

0 (0x0)

Specifies that the RF input channel is AC-coupled. For low frequencies (<10 MHz), accuracy decreases because RFmxInstr does not calibrate the configuration.

RFMXINSTR_VAL_CHANNEL_COUPLING_DC_COUPLED

1 (0x1)

Specifies that the RF input channel is DC-coupled. The RFmx driver enforces a minimum RF attenuation for device protection.