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Product Description

The Model 91 provides full duplex synchronous serial data communication from 150 BPS to 19.2 KBPS. The Model 91 can also be linked to establish a full duplex bus network between a host and a number of remote terminals. Opto isolation assures that devices connected to the Model 91 are electrically isolated from each other thereby eliminating problems associated with potential differences between grounds. Multi-dropped operation is achieved using a daisy chained approach to system wiring. With this concept each Model 91 regenerates each signal before passing it on the link. This process of incorporating signal repeaters results in extremely high data reliability especially at long distances. At 19.2 KBPS the Model 91 will support link distances of one mile. Six front panel indicators, including Power, DTR/RTS, DCD, CTS, TD and RD, provide a real-time status report.

The Model 91 accommodates the host device via a 25 Pin RS-232 female connector and connects to the communications link with screw terminals for either one set or two sets of 4-wire lines. Power is supplied by a wall mounted low voltage transformer.

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