Specifications

M&C and Interfaces SDM-309B Satellite Modem
4-4–38 MN/U-SDM309B Rev. #
This connector is the interface for the unbalanced external reference clock input. The
unbalanced external reference clock signal on J9 is selected by SW3. Refer to Section
4.2.2.11.5 for further information on selection of the balanced or unbalanced external
reference clock signal.
4.2.2.10.10 ESC Channel (J10)
The ESC channel interface is provided on a 25 pin “D” female connector and is located
on the front of the breakout panel. Screw locks are provided for mechanical security of
the mating connector.
Signal Function Name Pin Number
GROUND GND 1, 7
TERRESTRIAL TX DATA TERTXDAT 2
TERRESTRIAL RX DATA TERRXDAT 3
REQUEST TO SEND RTS 4
CLEAR TO SEND CTS 5
DATA SET READY DSR 6
Note: RTS and CTS are looped together on the connector.
4.2.2.10.11 Faults (J11)
The faults are provided on an eight position terminal block located on the front of the
breakout panel.
Signal Function Name Pin Number
GROUND GND J11-1, J11-5
PRIMARY COMMON PRI_COM J11-2
PRIMARY NORM/OPEN PRI_NO J11-3
PRIMARY NORM/CLOSED PRI_NC J11-4
SECONDARY COMMON SEC_COM J11-6
SECONDARY NORMALLY OPEN SEC_NO J11-7
SECONDARY NORMALLY CLOSED SEC_NC J11-8
4.2.2.10.12 Data Interface (J12)
The Data interface is provided on a 50 pin female "D" connector accessible from the rear
of the breakout panel. Screw locks are provided for mechanical security of the mating
connector.
Signal Function Name Pin Number
GROUND GND 1, 2
DROP DATA INPUT DDI-A
DDI-B
34
18
EXTERNAL CLOCK EXC-A
EXC-B
35
19
INSERT DATA OUTPUT IDO-A
IDO-B
36
20