Patton electronics 2720/I Series, User Manual

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Switch S2-6 and S2-7: Clock Mode
Set Switch S2-6 and S2-7 to determine the 2720’s transmitter tim-
ing.
S2-6 S2-7 Clock Mode
Off Off Network Clock . Transmitter timing is
derived from the received line signal.
On Off Internal Clock . Transmitter clock is
derived from an internal oscillator.
NOTE 1:
When using the Model 2720 as a high-speed short
range modem, one unit of the link must be configured in Internal
Clock mode, and the opposite end unit must be configured for
Network Clock mode.
If the ERR LED on the front of the unit is flashing (or on) it could
be an indication of a clocking problem. Double check your clock
mode settings and Tx Clock Invert S1-3 settings.
Switch S2-8 Reserved
Substitution (B8ZS) : This mode assures proper bit density
in the data stream. In this mode any data pattern can be
transmitted without causing ones density errors. This mode
allows for 64 kbps clear channel timeslots.
Switch S2-5: DS0 Channel Rate
Use Switch S2-5 to set the DS0 rate.
SW2-5 Setting
Off 56 kbps
On 64 kbps
9
10
S2 SUMMARY TABLE
Position Function Factory Default Selected Option
S2-1 Data Rate On
S2-2 Data Rate On
S2-3 Data Rate On
S2-4 Framing & Coding Off
S2-5 DS0 Rate On
S2-6 Clock Mode Off
S2-7 Clock Mode Off
S2-8 Reserved Off
1.536 Mbps
(DTE Rate)
ESF/B8ZS
64 kbps
Network
Reserved
Network