National Instruments 781036-01

The National Instruments 781036-01 is a dual-channel RF attenuator, also known as PXI-5695, designed for a frequency range of 50 MHz to 8.0 GHz. Featuring one fixed channel (Channel 0) and one programmable channel (Channel 1), the device is versatile for various RF attenuation needs. Channel 0 provides a fixed attenuation level with a calibration accuracy of ±0.7 dB, capable of handling a maximum input power of +33 dBm, ensuring robust performance while safeguarding against damage at the same threshold. This channel supports DC coupling with an input voltage tolerance of ±10 V and maintains its accuracy and power capacity with a relay switch time limited to 5 ms. Channel 1, on the other hand, offers a programmable attenuation resolution of +0.5 dB, with a similar calibration accuracy of ±0.7 dB and an attenuation settling time of +4 μs. The maximum operational input power for Channel 1 is +27 dBm, also adhering to a strict limit to prevent damage.

The 781036-01 requires a +3.3 VDC rail with a maximum current draw of 660 mA, typically operating at 250 mA, resulting in a maximum power consumption of 2.2 W. The device also draws power from +12 VDC rail with a maximum current of 528 mA (up to 7.0 W power draw) and -12 VDC rail requiring 508 mA (6.1 W). All input and output ports utilize SMA female connectors to ensure a 50 Ω impedance. While Channel 0 employs DC coupling, Channel 1 is configured for AC coupling. The module has a compact design, measuring 21.6 cm × 2.0 cm × 13.0 cm and weighing 263 g, designed for indoor applications. It meets IEC 61010-1, EN 61010-1, UL 61010-1, and CSA C22.2 No. 61010-1 safety standards, operating efficiently within an ambient temperature range of 0 to 55 °C and supportive of storage temperatures between -40 to 71 °C. Additionally, it functions within relative humidity levels of 10% to 90% during operation and 5% to 95% during storage, both non-condensing.