Symmetricom ET6000, User Manual

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OPTION DESCRIPTIONS
GPS OPTION 33D T1 FRAMED ONES - BALANCED OUTPUT
ASSEMBLY 55155-2
GPS OPTION 33E E1 FRAMED ONES - BALANCED OUTPUT
ASSEMBLY 55155-12
1.0 INTRODUCTION
This optional assembly (Option 33D - T1 or Option 33E - E1) uses a DS1 (or a CEPT)
Telecommunications Synthesizer and can serve as a stand alone Stratum 1 Master Clock when
installed in an instrument that has a Rubidium Oscillator as its time base. Or it can be a
component of a master clock system. This assembly can be installed in locations J7/J9 J8/J10 or
J18/J22 J19/J23 of the GPS Option 40 Motherboard Assembly. For the location of the 55155-2
(or 55155-12) Assembly and the rear panel output connector designations, characteristics, and
locations, refer to the GPS Option/Connector Configuration Sheet located inside the cover of the
ExacTime User’s Guide.
For a more in-depth description of T1 and/or E1 and the options provided on this assembly, refer
to the following:
•
CCITT Standards G.704, G.706, and G.732.
•
Also ATT pub 43801, ATT C.B. #142, and ATT C.B. #144.
1.1 GENERAL DESCRIPTION – GENERATION OF T1 (1.544MHz)
•
Assembly 55155-2 generates the T1 (1.544MHz) framed all ones, DS1 signal and associated
outputs. It provides the following input/outputs on a rear panel (20) pin connector. The
connector pin assignments are as follows:
Pin Signal
1 Balanced 1.544MHz framed all ones, DS1 Hi.
2 Aux. Alarm Relay Common Contact.
3 Balanced 1.544 MHz framed all ones, DS1 Hi.
4
Aux. Alarm Relay Normally Closed Contact.
5 Output Transformer Center Tap.
6 Aux. Alarm Relay Normally Open Contact.
7 Alarm Relay Normally Open Contact.
8 Alarm Relay Common Contact.
9 Alarm Relay Normally Closed Contact.
10
Not Used.
11 SYNC Input.
12 Sync Input Return.
13 8kHz TTL Output.
14 GND.
15 1.544MHz TTL Clock Output
Symmetricom Inc ET6xxx ExacTime GPS TC & FG (Rev C) C-65