Terminology Electro Mechanical Switch

Active Components > Pin Diode Switch

SPDT Switch - A single-pole, double-throw switch has one input port and two selectable output ports.
SPDT Terminated Switch - A single-pole, double-throw switch with one open output RF port internally terminated in a 50-ohm resistive load.
Multi-position Switch - A switch with one input and more than two outputs. Standard CEI multi-throw switches provide up to 6 selectable outputs from a single input.
Multi-position Terminated Switch - A multi-position switch with each unused or open output RF port internally terminated in a 50-Ohm resistive load.
Transfer Switch (DPDT) - A transfer switch has two independant paths that operate simultaneously in either of two selected positions.

Actuator Terminology

Failsafe - A mode of operation in which the switch moves to the closed position when the actuating voltage is applied and always returns to a predetermined position when the voltage is removed.
Latching - Also called pulse latching, a mode of operation in which the switch remains in a preselected position whenever the actuating voltage is removed or interrupted, and holds that preselected position until a voltage is applied to another position.
Momentary (normally open) - A mode of operation in which all output ports of the switch are disconnected from the input port until a voltage is applied to maintain a selected position. The switch returns to its open position with the removal of voltage.

Electromechanical Switch Options

Indicator Circuitry - A set of internally mounted contacts mechanically connected to the switch actuator allowing external monitoring of switch RF status.
Suppression Diodes - This option offers fast-recovery rectifiers (diodes) connected in parallel with the coics of the switch to suppress any transient voltage generated by the coils. Suppression Diodes are recommended with TTL Logic.
TTL Logic - Transistor-transistor-logic driver circuitry which enables the status of the switch to be controlled by the level of the TTL logic input.
Cut off Power Circuit - This applies to a latching switch only. A switch that has the ability to disconnect the actuator drive circuit so that D.C. current will not be consumed after switching has been accomplished.
Low or Ultra Intermodulation - This option allows for a -110 dBc (LOW) or -130 dBc (ULTRA LOW) passive intermodulation (PIM) level @ the PIM frequency. PIM is a form of signal distortion that occurs whenever signals at two or more frequencies conduct simultaneously in a passive device which contains some non-linear response.