Passive Devices

FM combiners (87,5...108 and 66...74 MHz) are used to combine signals of two or more radio transmitters into a single antenna-feeding route. They are based on band-pass two- or three-cavity filters and can be of bridge or starpoint type. Minimum transmitters frequency spacing is 0,8 MHz. At present we produce combiners with output power up to 20 kW. Maximum number of inputs is 5.

Kvant-Efir also produced a couple of combiners to combine signals of two FM transmitters and one 3rd channel TV transmitter, FM transmitter and 5th channel TV transmitter.

TV combiners are used to combine signals of two or more TV transmitters into a single antenna-feeding path. There are different types of combiners depending on frequency spacing, channel isolation needed, bandwidth etc.: starpoint combiners, bridge combiners, stretchline combiners.

Starpoint combiners are the simplest ones but they are produced for certain channels only and the minimum channel spacing is 4. There are only two-channel starpoint combiners and the maximum output power is 4 kW.

Bridge combiners are the most versatile combiners. They can be a base for multi-channel combiners as they have a broadband input. Bridge combiners can be adjusted within the entire UHF band (21—69 TV channels). Maximum output power of the combiners is 30 kW. Minimum channel spacing is 1.

Stretchline combiners take an interim position between bridge combiners and starpoint combiners. They combine two signals of specific TV channels and the minimum channel spacing is 2. Maximum output power is 4 kW.

Multi-channel combiners are made on the basis of two-channel combiners of different types: bridge combiners, starpoint combiners, stretchline combiners. Maximum number of inputs is 8. Maximum output power is 30 kW.