The -TPS3A modules are three-pair audio sending modules compatible with RDL Format-A twisted pair products. These modules are designed to be mounted in wall boxes, cabinets or other enclosures that allow users to connect audio sources. The D- and DS- models mount in RDL WB-1U and WB-2U wall boxes, or in standard U.S. electrical boxes. The D-TPS3A features a white front-panel laminate with gray lettering that matches RDL Decora©-style remote controls. The DS-TPS3A is constructed of stainless steel to coordinate with RDL Decora-style stainless steel remote controls in commercial/industrial installations. The AF-TPS3A is an APPFLEX series product that is compatible with various APPFLEX wall-mount, cabinet-mount and tabletop enclosures. The EM-TPS3A is a 45mm square module that fits the European Modular mounting frames and cover plates. European electrical boxes are not sufficiently deep to accommodate RJ45 jacks and plugs, therefore the EM- products connect to the twisted pair cable through a detachable terminal block. The -TPS3A modules features an XLR microphone input and two RCA phono jack inputs, one for the left channel source and one for the right channel source. The unbalanced inputs are designed to receive standard -10 dBV consumer level signals. The microphone input provides 24 Vdc IEC phantom voltage and accepts both dynamic and condenser microphone signals. The input signals are amplified using studio-quality preamplifiers optimized for normal operating levels. A rear-panel GAIN switch is provided to set the amplification of the microphone preamplifier. This switch is normally set by the installer for NORM (normal) gain. If consistently low mic levels are expected, this switch may be set to the HIGH gain position. The pre-amplified microphone source is routed to pair A. The buffered left and right line-level inputs are routed to output cable pairs B and C. These modules drive all three FORMAT-A cable pairs, so they are not equipped to receive inputs from other sender modules. The -TPS3A may not be connected together with any other sending modules. The -TPS3A may be powered directly from a 24 Vdc power supply using the rear-panel detachable terminal block. Local power connected to the module is also fed to all connected remote modules. The -TPS3A may be remotely powered through the twisted pair cable from any other module, signal distributor or RDL power inserter connected to the same twisted pair cable. Module power is indicated by a front-panel LED. RDL FORMAT-A features superior audio performance that rivals or exceeds shielded wiring. Design simplicity, ease of installation, unsurpassed flexibility, automatic fused power, exceptional hum rejection, low noise, and low distortion provide designers and installers the optimum choice in economical twisted pair products.