Installation
SW3-5 − Transmitter Termination
SW3-5 ON = Switched by RTS
OFF = 600 Ω
SW3-5 is used for multi-point configuration networks. When multiple modems are connected on the same metallic circuit:
The transmitter termination should be of high impedance if the modem is not transmitting.
The transmitter is only terminated with 600 ohms when RTS is asserted.
This configuration should be used for all slave modems to prevent the transmitting modem from being unnecessarily burdened. To select this configuration, set SW3-5 ON on the slave modems.
If you use the modem with transmission lines that are transformer- coupled or with an impedance-isolated network (such as a transformer bridge), set SW3-5 OFF for proper operation.
SW3-6 − Reserved (Test Only)
SW3-6 Must be OFF
SW3-6 must be in the OFF position for normal operation.
SW3-7 − 2-/4-Wire Operation
SW3-7 ON = 2-Wire, Half-Duplex Mode
OFF = 4-Wire, Full-Duplex Mode
SW3-7 configures the modem for 4-wire full-duplex or 2-wire half- duplex operation.