National Instruments SCXI-1190

The National Instruments SCXI-1190 is a Quad 4-Channel Multiplexer Module designed to facilitate signal switching from DC up to 1.3 GHz. With a maximum voltage rating of 24 V and a current rating of 1 A, this module excels in low-power switching applications. The SCXI-1190 operates under the control of NI-SWITCH within various application development environments, including C/C++, LabVIEW, Visual Basic, and LabWindows/CVI. It features a reflective switch design, meaning channels not connected to the common channel remain unterminated, which can cause the signal to reflect to the source. While this characteristic typically poses no issue for low-power applications, caution is advised when interfacing with high-power RF sources, as unterminated outputs could damage such components.

The relay contacts on the SCXI-1190 boast a mechanical lifespan of up to 5 million actuations under minimal signal conditions, though using the module with high-power loads may lead to arcing, shortening overall contact life. This multiplexer module includes five SMB male connectors for each of its four banks, providing a characteristic impedance of 50 Ohms. It supports a maximum switching power of 24 W per channel, with rise times under 300 ps, signal delay times of less than 3 ns, and relay operate and release times of 15 ms. Notably, it can handle up to 10 W of maximum RF carry power at 900 MHz per channel. While National Instruments has announced the SCXI-1190 as obsolete, it remains available for purchase and repair through Apex Waves.