tions and decodes them as zeros. This method enables the network to meet minimum pulse density requirements.

•Bipolar 8 Zero Substitution (B8ZS): This mode assures proper bit density in the data stream. In this mode any data pattern can be trans- mitted without causing ones density errors. This mode allows for 64 kbps clear channel timeslots.

Switches S1-2 and S1-3: Line Build Out. Line buildout (LBO) is a T1 equipment feature, it controls the transmitter signal strength and pulse shape sent over the T1 line. For most applications, the default settings (0 dB) will suffice. When connecting to a carrier’s T1 circuit, the carrier will determine what LBO is necessary. 0 dB provides the highest signal strength, and therefore the longest distance, while -15.0 dB provides the lowest usable signal level. -22.5 dB is used to test the line and should not be used in normal applications.

Transmitted E1 signals are not specified in terms of LBO. Patton’s Model 1194/E1 complies with ITU-T G.703 recommendation for signal pulse shape and amplitude, and has a reach of 1.6 km. No user configuration is required

S1-2

S1-3

Function

 

 

 

ON

ON

0dB

OFF

ON

-7.5dB

 

 

 

ON

OFF

-15.0dB

 

 

 

OFF

OFF

-22.5dB

 

 

 

Switches S1-6 and S1-7: Clock Mode. Use switches S1-6 and S1-7 to determine clock mode of the 1194.

S1-6

S1-7

Setting

Description

 

 

 

 

ON

ON

Internal

Transmit clock generated internally

ON

OFF

Receive

Transmit clock derived from the fiber

 

 

Recover

line link

 

 

 

 

OFF

ON

Network

Transmit clock derived from E1 or T1

 

 

 

equipment interface

 

 

 

 

OFF

OFF

Internal use only

 

 

 

 

 

Note The Model 1194 units are intended to work in pairs. Set the clock modes for the Model 1194 units with one end of the link set for receive recover and the other end set for either internal or network.

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