NIRFSA_ATTR_RF_ATTENUATION_STEP_SIZE

NIRFSA_ATTR_RF_ATTENUATION_STEP_SIZE

Specific Attribute

Description

Specifies the step size for the RF attenuation level. The actual RF attenuation is coerced up to the next highest multiple of this step size. You can also set this value to change the step size for the device within the supported device precision and configuration.

PXI-5600—The device configuration supports only the following attenuation step size values: 10, 20, 30, 40, and 50.

PXIe-5601—The attenuation is calculated based on the actual calibrated value closest to the desired value, so the step size varies as the actual gain values vary between consecutive attenuation settings.

PXIe-5603—The device configuration supports attenuation changes in 1 dB steps.

PXIe-5605—The available attenuation step size depends on the specified center frequency. In the high band signal path (input frequencies greater than 3.6 GHz), the only available attenuation is the step attenuator that you can change in 5 dB steps. In the low band signal path (input frequencies less than or equal to 3.6 GHz), an additional 31 dB of solid-state attenuation is available in 1 dB steps. The 5 dB default value indicates that, even when in the low band signal path, NI-RFSA changes the attenuation in 5 dB steps using only the mechanical attenuator. You can use this attribute to affect when the device changes the attenuation settings. To use the solid-state attenuation in the low band signal path, change the step size to a value other than a multiple of 5 (for example, a step size of 1 dB). If you use a value other than a multiple of 5 while in the high band of the PXIe-5605, NI-RFSA returns an error.

Units: dB

Valid Values:

PXI-5600/5661—10, 20, 30, 40, and 50

PXIe-5601/5663/5663E—0.0 to 93.0, continuous

PXIe-5603/5665 (3.6 GHz)—1.0 to 74.0, in 1 dB steps

PXIe-5605/5665 (14 GHz) (low band), PXIe-5606/5668 (low band)—1.0 to 106.0, in 1 dB steps

PXIe-5605/5665 (14 GHz) (high band), PXIe-5606/5668 (high band)—5.0 to 75.0, in 5 dB steps

PXIe-5667 (3.6 GHz) using the PXIe-5693 RF preselector low frequency bypass path—1.0 to 74.0, in 1 dB steps

PXIe-5667 (3.6 GHz) using the PXIe-5693 RF preselector filter path— 1.0

PXIe-5667 (7 GHz) using the PXIe-5693 preselector low frequency bypass path— 1.0 to 106.0 in 1 dB steps

PXIe-5667 7 GHz) using the PXIe-5693 RF preselector filter path— 1.0

Default Value:

PXI-5600/5661—10.0

PXIe-5601/5663/5663E—0.0

PXIe-5603/5665 (3.6 GHz)—1.0

PXIe-5605/5665 (14 GHz), PXIe-5606/5668—5.0

PXIe-5667—1.0

Supported Devices: PXI-5600, PXIe-5601/5603/5605/5606 (external digitizer mode), PXI-5661, PXIe-5663/5663E/5665/5667/5668