GE MDS DS NX915 User Manual

MDS NX915 Integrator’s Guide

Part No. 05-6697A01

1.0 INTRODUCTION

The MDS NX915 (Figure 1), is a multi-modem modular system offering both Freque ncy Hopping Spread Spectrum
and DTS transceiver modes that are designed for use in the license-free 902-928 MHz band. The unit is designed for
use inside data equipment to provide reliable connectivit y in wireless networks.

The NX915 power control circuit ensures that the RF output never exceeds +30 dBm at the antenna connector. The
module is designed for OEM use only. Host systems, if used with antennas having standard connectors, must be
professionally installed. Host systems using integrated antennas or unique antenna con nectors must be factory
configured by the OEM to operate at the correct output power setting. Refer to the table at the end of this guide to
determine applicable antenna types and the RF output power allowed.

1.1 Transceiver Features

The NX915 maximizes performance and flexibilit y in wireless networks, offering the following key features:

•Up to 81 channels over 902–928 MHz, divided into multiple zones

•User-selectable option to skip sub-bands with interference

•Multiple available network addresses

•Network-wide configuration from the Master station, eliminating most trips to Remote sites

•RSSI and LQI readback indicators

•Poor load VSWR detection alarm indicator

•Store-and-Forward repeater operation

•Same hardware for Master, Remote, or Store-and-Forward configurations

•Supports RS/EIA-232(TTL), Ethernet, and USB user interfaces

•Operates at 4.5 Vdc at the MiniPCIe card edge power connections

Figure 1. NX915 Transceiver Module

(Mini PCI-Express Card Edge for Data/Power/& I/O and J300 Antenna)

NOTE: Some features may not be available on all units, based on the options purchased, or regulatory constrai nts in
the country of operation.

2.0 INSTALLATION

The transceiver is designed for installation in existing electronic equipment. The I/O and power connections are made
through the Mini PCI-Express card edge and it mounts to the host heatsink assembly using two #4 screws inside the
RF can area. The required heatsink contact area on the bottom surface of the PCB has the solder mask removed for
proper heat transfer.

Only one cable connection is required to the radio for the J300 Antenna connector. Note that the module does have
four optionally populated status LEDs (CR100, 101, 200, and 201) that indicate operating mode details. These LEDs
provide important information that is useful during startup and optimization of the radio link.

Antennas used with the radio can be either a Yagi directional type (often used at remote sites) or an omni-directional
type used for short range applications or at Master stations. Contact your sales representative for information on
available antennas.

Follow these steps to install the transceiver module:

1. Power down the Host assembly the module is being installed in to.

2. Mate the MiniPCIe card edge of the module into the socket on the Host assembly.

3. Secure the module to the heatsink surface using two #4 screws through the mounting holes in the corners of
the RF can area on the radio’s PC board.

3. Install the RF shield over the transceiver section.

4. Select and install an appropriate antenna and feedline for your system coverage requirements.

5. Connect the antenna coaxial lead to J300 on the module. It accepts a Type-TNC male coaxial connector.

- For antenna gains higher than 6dBi, the system has been approved only with the following types:
a. MDS PN: 97-3194A23 (Manuf. PN: Z2402 from PCTEL, Inc.), 7dBd (9.15 dBi), Omnidirectional
b. MDS PN: 97-3194A14E (Manuf. PN: Z2342 from PCTEL, Inc.), 10dBd (12.15 dBi) Yagi

6. Host Power Supply Requirement: The input power applied to the unit must be 4.5 Vdc (-/+0.05 V).
See Table 1 for power supply interface connections.

Table 1. NX915 Power Supply Connections

7. Set the radio’s basic configuration with a PC terminal through the Host system. The three essential settings for
all transceivers are (See Section 3 for commands):

•Frequency

•Power

•Modem

8. In a normally operating system, you will see the CR100 POWER LED turn on at start-up.

9. Optimize the installation by checking:

•Antenna aiming and SWR check

•Optimal baud rate setting

•Radio interference checks

3.0 RADIO PROGRAMMING

There are no manual adjustments on the radio. All programming and control is performed through a PC connected to
the Host platform that interfaces with the radio’s J200 MiniPCIe card edge connector.

3.1 User Commands

The following tables provide descriptions of the various user commands for the transceiver.

Table 2. NX915 User Commands