Multitech MT56DSU-R, Руководство пользователя

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MT56DSU-R Owner's Manual
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Wire Gage
Data Rate 19 AWG 22 AWG 24 AWG 26 AWG
2400 bps 22.0 15.0 12.0 9.5 miles
4800 bps 19.0 13.0 10.0 8.0 miles
9600 bps 15.0 10.0 7.0 5.5 miles
19200 bps 11.9 7.0 5.0 4.0 miles
56000 bps 10.0 6.0 4.2 3.0 miles
Note that line characteristics will vary depending on cable type/
manufacturer, splices, bridge taps, etc.
An example of a typical LADS application is shown in Appendix A of
this manual.
3.4.2 Off-Net Extension Applications
The MT56DSU-R can be used as an off-net extension with standard
analog modems and lines to complete DDS circuits in areas where
the DDS is not available or where a customer requirement is for an
extension of the circuit for a special application.
In applications using the MT56DSU-R for an off-net extension, one
MT56DSU-R may be set for External Timing and the other set for
DDS Timing; however, in this application, the clock (timing) being
supplied must be accurate to +/-0.008% of the enabled data
transmission rate.
The Elastic Store option is used in off-net extension applications
with analog modems to compensate for small timing phase drifts
that typically occur in such applications. A “cross-over” cable is
required to connect the MT56DSU-R DTE connector to the analog
modem in this application.
The analog modem at the same end as the MT56DSU-R must have
External Timing enabled; the modem at the end of the off-net
extension must have Slave Timing enabled.
In MT56DSU-R applications that use controlled carrier, the CTS
delay for the analog modem at the end of the off-net extension must
be longer than the CTS delay of the MT56DSU-R.
An example of a typical off-net extension application is shown in
Appendix A of this manual.
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