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Product Description

The Model 242, X.21 to RS-232 Interface Converter, performs full duplex conversions from 0 to 64 KBPS on Tx/Rx Data, Request-To-Send (RTS), Data Carrier Detect (DCD) and Transmit /Receive Clock (TC and RC). X.21 uses a differential signaling technique called RS-422, while RS-232 uses a single line bipolar driving technique. The RS-232 port is a male DB25 connector wired to appear as a DCE. The X.21 port complies with the Public Data Network, and is available on a male DB15 connector that is wired to appear as a DTE. Power for the Model 242 is derived from the data and control signals. Internal jumpers provide the user with the ability to selectively place terminating resistors on the inputs to the three receivers. The input/output lines on the X.21 port are surge protected to eliminate threats on long X.21 cable runs.

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