Multiplexers
Introducing the SD4000
The SD4000 and SD4000R series of multiplexers are designed to enable two transmitters / receivers to operate, together with an untouched broadcast radio take-off, through a single working aerial.
In addition to providing the facility of operating two communication radios, the SD4000 range incorporates matching sections that allow the aerial system to be "tuned" to each of the radio systems. This matching of the system ensures maximum power transfer, together with maximum aerial effciency, which leads to increased range.
The very low insertion losses ensure that this enhanced performance is not dissipated by matching and splitting losses.
Comparison Between Active & Passive Multiplexers
The 4-port Multiplexer series falls into two main categories, namely SD4000R (active) and SD4000 (passive).
The passive range, which are the SD4000 variants, require no switching, signalling or voltages and can therefore be introduced very simply into any aerial system. Versions are available for both wide and narrow band frequency operation on all wave bands.
The separation between the operating frequencies of the two transmitters and receivers in the SD4000 should, ideally, be greater than 20%. Frequency separations of less than 20% require the active SD4000R models, which are identical in size.
Their low power consumption of around 50mA together with a voltage tolerance of between 9.5 and 16 volts, allows them to draw power from either of the communication radios, or the vehicle battery.
The SD4000R will operate with any mix of transmitter / receiver frequencies. As it is able to operate with a common frequency on both communication radios, only one transmitter can operate at any one time, the opposite receiver being switched out during the transmitter ON time.
The SD4000R functions on transmitter ON signalling from the associated transmitters, switching time being less than 5mS to ensure protection to the adjacent receiver.
The SD4000 range is ideally suited to multi-radio covert applications where additional aerials are not acceptable and where uninterrupted Broadcast reception is essential to the maintainance of the coverage image.
As with the SD3000 units, the SD4000 and SD4000R are pre-aligned prior to despatch from the factory.
For further information on the range of multiplexers, please do not hesitate to contact us on +44 (0)151 334 9160. Furthermore, please ask about our bespoke design service.
Specifications
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