Patton electronics 1140RC User Manual page 7

S1-5 and S1-6: Clock Source
Switches S1-5 and S1-6 are set in combination to determine the
transmit clock source for the Model 1140RC.
S1-5
On
Off
On
S1-7: Asynchronous/Synchronous Mode
The setting for switch S1-7 determines whether the Model 1140RC
is in asynchronous or synchronous operating mode.
S1-7
On
Off
S1-8: Carrier Control Method
The setting for switch S1-8 determines whether the carrier is
"constantly on" or "controlled by RTS". This setting allows for operation
in switched carrier, multipoint and/or hardware handshaking
applications.
S1-8
Off
On
S1-6 Setting
On Internal transmit clock
On Receive recover clock
Off External transmit clock
Setting
Asynchronous
Synchronous
Setting
Constantly On
Switched Carrier
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