Comtech EF Data CDM-700 - Manual (Page 44)

CDM-700 High Speed Satellite Modem Revision 5
Physical Description MN/CDM700.IOM
4.3.3 Rx and Tx IF Connectors (J1 and J3)
These connectors depend upon whether 70/140 or L-Band operation is chosen. Refer to Chapter 5.
4.3.4 10/100 Ethernet Remote Port Connector (J4)
The Ethernet connector is a RJ45 type female.
4.3.5 SerDes (Private Communications Link) (J6)
The SerDes connector is a type RJ45 type female. This connector is a private communications
link and NOT for customer use.
4.3.6 External Reference Connector (J7)
The Ext Ref (External Reference) input is a female SMA connector used to supply a master
reference to the entire chassis. The clocks on the Framer Card and the Modulator and
Demodulator Synthesizers are locked to this input, when it is used.
4.3.7 Alarm Form C Connector (P1)
The Alarms connector is a 15-pin 'D' type male (DB15-M). This provides the user with access to
the Form-C relay contacts, which indicate the fault status of the unit. These are typically
connected to an external fault monitoring system, often found in satellite earth stations.
In addition, the receive I and Q demodulator samples are provided on this connector. Connecting
these signals to an oscilloscope in X,Y mode will provide the receive signal constellation
diagram, which is a useful diagnostic aid.
A pin is also provided which can mute the transmit carrier. This requires that the pin be shorted to
ground, or a TTL ‘low’. The Renduancy feature must be disabled when using alarm connector to
view I and Q samples.
As an aid to antenna pointing or for driving step-track equipment, an analog AGC signal is
provided on Pin 2 of this connector.
4.3.8 Remote Control Connector (RS-232/RS-485), P2
The Remote Control connector is a 9-pin 'D' type male (DB9-M). Access is provided to remote
control ports of the modem, both RS-232 and RS-485.
4.3.9 Data Interface Connector
Refer to Chapter 5 and the Appendicies for applicable interfaces.
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