Pelco PTZ driver units,
                      connections for RS485/RS422.

         Video Encoder               Pelco PTZ unit

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RS485 2-wire
simplex communication

                Terminal             Terminal
             RX/TX  A+ --------------- RX+
             RX/TX  B- --------------- RX-

                         Not connected TX+
                         Not connected TX-

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RS485/RS422 4-wire
full duplex communication

                Terminal             Terminal
             RX/TX  A+ --------------- TX+
             RX/TX  B- --------------- TX-

                TX  A+ --------------- RX+
                TX  B- --------------- RX-


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RS485 2-wire
simplex communication
                                     Pelco Esprit
                Terminal             Terminal
             RX/TX  A+ --------------- RX+ Red wire
             RX/TX  B- --------------- RX- Green wire

                         Not connected TX+ White wire
                         Not connected TX- Black wire

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RS485/RS422 4-wire
full duplex communication
                                     Pelco Esprit
                Terminal             Terminal
             RX/TX  A+ --------------- TX+ White wire
             RX/TX  B- --------------- TX- Black wire

                TX  A+ --------------- RX+ Red wire
                TX  B- --------------- RX- Green wire

===============================================================

RS485 2-wire
simplex communication
                                     Pelco Spectra Mini Dome
                Terminal             Terminal
             RX/TX  A+ --------------- RX+ White/Green wire
             RX/TX  B- --------------- RX- Green wire

                         Not connected TX+ White/Blue wire
                         Not connected TX- Blue wire

===============================================================

RS485/RS422 4-wire
full duplex communication
                                     Pelco Spectra Mini Dome
                Terminal             Terminal
             RX/TX  A+ --------------- TX+ White/Blue wire
             RX/TX  B- --------------- TX- Blue wire

                TX  A+ --------------- RX+ White/Green wire
                TX  B- --------------- RX- Green wire

===============================================================