RF Switch

General Microwave switches cover the frequency range from 100 MHz to 40 GHz, and come in a variety of configurations. The terms pole and throw are used to describe switch contact variations. The number of “poles” is the number of separate circuits controlled by a switch, and the number of “throws” is the number of separate positions that the switch can adopt.  Here are some examples:

A single-pole, single-throw switch (abbreviated SPST) is a simple on-off switch, which can be used to control the switch the power supply to a circuit. In a SPST switch, there is a pair of contacts that can be either closed or open.

A single-pole, double-throw (abbreviated SPDT) switch can be on in both positions, switching on a separate device in each case. For example, a SPDT switch can be used to switch on a red lamp in one position and a green lamp in the other position.

General Microwave switches are available in various topologies, ranging from single-pole single-throw, to single-pole eight-throw (SP8T, in which a single switch can alternatively turn on eight separate devices).

Microwave switches can be either reflective or absorptive. In a reflective switch, the impedance of the port that is OFF will have a very high VSWR (Voltage Standing Wave Ratio), the ratio between the maximum and minimum voltages in a standing wave]. The high VSWR indicates a loss of signal power resulting from the reflection caused at a discontinuity in a transmission line. A high reflection loss, however, will indicate that there is a low loss of power upon insertion of a device (insertion loss). On the other hand, an absorptive switch will have a low VSWR on each port, regardless of the switch mode. This indicates a minimum of power loss in the transmission line.

General Microwave switches are available in both reflective and non-reflective configurations, and a non-reflective SP16T unit.

Model F192A Non-Reflective Ultra-Broadband High-Speed SPST Switch High speed 0.2 to 18 GHz frequency range 80 dB isolation Non-reflective Low VSWR and insertion loss Small size, light weight	Series 91 and 92 Miniature Broadband SPST Switches Frequency range (Series 91): 1 to 18 GHz Frequency range (Series 92): 0.2 to 4 GHz Low VSWR and insertion loss Up to 80 dB isolation Less than 10 nsec rise and fall time Miniature size, light weight
F940H Broadband Transfer Switch Frequency range: 0.5 to 18 GHz Low VSWR and insertion loss Isolation: up to 60 dB Small size, light weight

Herley – General Microwave specializes in developing and producing customized microwave components and millimeter wave products for the defense and aerospace industries as well as for non-defense applications such as communication systems. Herley General Microwave produces the industry standard General Microwave line of off-the-shelf catalog RF componentד. If you are looking for a Solid State Power Amplifier, Microwave Synthesizer or other microwave oscillators, Microwave Receiver, RF Switches, Microwave attenuator, Microwave Limiter, Microwave Phase Shifter, or Microwave IQ Vector Modulator we can produce components meeting your requirements at a very competitive price. We also produce high quality customized Integrated Microwave Assemblies such as Up and Down Converters, DLVAs, Beam Forming Networks, Front Ends, or Switched Bank Filters, that can be used in a wide variety of demanding applications. Herley General Microwave (HGMI), a subsidiary of Herley Industries provides solutions for electronic warfare systems, Phased Array Radar systems, electronic warfare simulators, test Equipment and test Systems and other defense and non-defense systems. We look forward to working with you, so please contact us today.