Fibersystem 21-1601, Техническое руководство

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General description
Functional
The modem 21-1601 and 21-1651 from Fibersystem are combined fiberoptic
synchronous and asynchronous modem with four different interfaces.
The interfaces are:
G.703 unbalanced 2Mbps,
G.703 balanced Nx64Kbps,
X.21
RS-530, not mounted on products produced after October 2006.
The modems are available in 2 versions.
21-1601 runs on 110-230 VAC , +/- 20%, power supply.
21-1651 runs on 48-250 VDC, +/- 20%, power supply.
The modem can be mounted in 19 rack with the mounting brackets included with the
product.
In synchronous mode the data rate are settable from 4.8kbps to 2048kbps.
To run the modem in asynchronous mode the data rate must be set to at least 8 times
the actual data rate giving a maximum asynchronous rate of 256kbps.
The modem can be configured to use three models of clock generation:
Internal clock, where the modem generates the transmit clock.
External clock, where the modem recovers the clock from the selected
interface.
Loop clock, where the modem recovers the clock from the fiber link.
The 21-1601 or 21-1651 can be connected to a telecom network or “back-to-back”.
The front panel is marked 21-16xx and the product is often referred to as “21-16xx”.
History
The 21-16xx has been delivered in 4 versions:
Product number Version
21-1601 ST multimode version with 100 –240 Volt AC/DC power supply
21-1651 ST multimode version with 48VDC power supply
21-1605 ST singlemode version with 100 –240 Volt AC/DC power supply
21-1655 ST singlemode version with 48VDC power supply
Present products
21-1601 Fo modem G703/X.21 (/RS530) 230V
21-1651 Fo modem G.703/X.21 (/RS530)
This manual will describe these products.
For singlemode application we recommend to use Fibersystem´s multimode to
singlemode converters, for example 21-203, “Fo MM/SM 4B/5B konv SC-SC
80km“.