National Instruments 782358-01 PXI Transfer Switch Module 

The National Instruments 782358-01 is also known as the PXI-2798 module. It is a top-notch Dual-Transfer Switch Module that is designed for routing RF and microwave signals in automated test applications. It offers the maximum scan rate of 5 cycles per second. The module operates with an insertion loss of less than 1 dB up to 40 GHz that makes it nearly transparent to signals at lower frequencies. This NI 782358-01 module is designed for both basic signal routing and complex tasks such as inserting and removing components in a signal path. It offers nominal characteristic impedance of 50 Ω, and low insertion loss from <0.3 dB to <0.8 dB across 6 GHz to 40 GHz frequencies. The part features open channel isolation of more than 70 dB up to 6 GHz that decreases slightly at higher frequencies but still maintain substantial isolation.

The module can handle a maximum RF carry power of 18 W up to 26.5 GHz and 10 W up to 40 GHz. The maximum current requirement per channel is 0.6 Arms. The required input switching voltage for this unit is 30 Vrms. It is important to note that the 782358-01 should not switch active RF signals to prevent potential damage from reflections. The NI 782358-01 module includes electromechanical, latching relays with an expected mechanical life of 2.5 million cycles.

The relays are manufactured by Radiall (R578 series) and feature gold-plated beryllium copper contacts. The module's I/O connector consists of 8 x SMA 2.9 jacks. The trigger input sources of this unit include PXI trigger lines <0...7> with a minimum pulse width of 150 ns. For output triggers, the pulse width is programmable from 1 µs to 62 µs. The physical characteristics of the transfer switch module include dimensions of 21.6 cm x 4.1 cm x 13.0 cm and a weight of 279 grams. It requires 2.5 W of power at 3.3 V, 1 W at 5 V, and 4 W at 12 V from the PXI power supply. It operates within a temperature range of 0 °C to 55 °C and the maximum allowable installation altitude is 2000 MSL.