Specifications

MDS 05-6628A01, Rev. A MDS Orbit MCR-4G Technical Manual 7

COM1 Port notes and wiring arrangements (RS-485):

The COM1 port supports 4-wire and 2-wire RS-485 mode.

· RXD+ / RXB and RXD– / RXA are data sent into the unit

· RXD+ / RXB is positive with respect to RXD– / RXA when the line input is a “0”

· TXD+ / TXB and TXD– / TXA are data sent out by the unit

· TXD+ / TXB is positive with respect to the TXD– / TXA when the line output is a “0”

Cell Antennas (AUX and MAIN)—These SMA coaxial connectors are for attachment of cellular antennas.

The MAIN connection is for basic cellular transmission/reception, and the AUX connector is for attachment

of a receive-only antenna which provides for MIMO receive operation (diversity) with standard for 4G mod-

ules, improving signal quality in many installations. In general, both antennas should always be used for

cellular operation. The GE MDS part number for this antenna type is 97-2485A04.

Figure 5. Directly-Connected Cellular Antenna (Typical)

(GE MDS Part No. 97-2485A04)

Table 3. COM1 Port Pin Details (RS-485)

Number

Input/Output Pin Description

1 Reserved

OUT DCD (Data Carrier Detect)

3 Reserved

4 Ground Connects to ground (negative supply potential) on chassis

5 OUT TXD+ (Transmitted Data +)—Non-inverting driver output. Supplies

received payload data to the connected device.

6 IN RXD+ (Received Data +)— Non-inverting receiver input. Accepts

payload data from the connected device.

7 OUT TX-/TXB (Transmitted Data -)—Inverting driver output

8 IN RX-/RXB (Received Data -)— Inverting receiver input