Black Box MD3310-R2, Руководство пользователя

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CHAPTER 15: Establishing Data-Communication Links with the Modem
15. Establishing Data-
Communication Links
with the Modem
The modem’s versatility allows data-communication links to be established using a
variety of different configurations. This, in turn, makes it possible to extend the
range of the modem and get around obstacles.
Figure 15-1 shows the most common and straightforward link, a master
communicating to a slave in a dedicated link.
Figure 15-1. Master Communicating to a Slave in a Dedicated Link.
Figure 15-2 depicts how a link might be set up using a repeater. The repeater may
be sitting on a hilltop or other elevated structure to link the master to the slave. In
this setup, you might want to use an external omnidirectional antenna on the
repeater; to extend the range, you could use Yagi antennas on either or both of the
master and slave.
When a repeater is used, the RF speed is cut in half, making 115-kbps
uncompressed throughput unachievable. The baud rate, however, may still be set
at 115200.
Figure 15-2. Setting Up a Link Using a Repeater.
Master Repeater Slave
Master Slave