12 Description TB9400 Installation and Operation Manual© Tait Limited March 20171.2 ModulesThe base station consists of a subrack with up to two transmit/receivechannels, or up to four receive-only channels.Receive-only base stations are currently available for operation only onB3 band (148MHz to 174MHz) and K4 band (762MHz to 870MHz)1.The single PMU (power management unit) supplies and manages power tothe whole subrack (refer to “Theory of Operation” on page 22). One reciterand one PA (power amplifier) are needed for each transmit/receive channel.The PA is not required for a receive-only base station. There is also a frontpanel with user controls and fans. The modules are interconnected at thefront of the subrack. External connections to the modules are located at therear.Modules come in different variants depending, for example, on the RFband or the supply voltage.Each module is inserted into the 4U subrack from the front and is securedat the front with a metal clamp. Both clamp and module are easily removedfor rapid module replacement. The modules are secured laterally withplastic guides that clip into the top and bottom of the subrack. These guidescan be easily repositioned to change the configuration of a subrack. Theheavier modules are also secured laterally by metal tabs at the rear of thesubrack.The following provides a brief description of the available modules.Subrack The 4U subrack is made of passivated steel and is designed to fit into astandard 19 inch rack or cabinet. The subrack is fitted with an interconnectboard that connects the system control bus and power to the modules andfront panel. The position of a module in the subrack is defined by the socketon the subrack interconnect board to which the module is connected by thesystem control bus.1. Refer to “Frequency Bands and Sub-bands” on page 18.
