Active (Combiner or Splitter)- An RF device that includes active components (amplifiers) to compensate for losses inherent in typical splitter/combiner circuits.

Agile Frequency Converter– A device that allows conversion of one frequency to another, either an up-converter or a down-converter, while allowing flexibility of programming frequencies.

Amplitude Balance- The property of a signal splitter having equal output levels.

Blocking Matrix– A matrix switch in which an input or an output may only be connected, one at a time, subsequent input or output reassignment will disconnect previous assignments.

Block Up-Converter- (BUC) Typically used to convert L-band signals to satellite uplink frequencies.

Combiner– A device used to combine multiple RF signals to a common output while maintaining impedance matching (See Active and Passive).

Decibel- Abbreviation dB; a logarithmic function used to simplify RF calculations; decibels may be added or subtracted; 0 dB is the standard reference level.

DC– Direct current, typically used to define RF input operating voltages.

1. Down-Converter- A device used to convert a signal of higher frequency to a signal of lower frequency.

2. DPDT– Double-pole double-throw switch.