Telenetics OM-AMPS-100 manual Electrical Interference, Distance from the Antenna to Omega

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Section 5

External Antenna Guidelines

Electrical Interference

Never locate an antenna near high voltage power lines. In addition, take into account any other sources of possible electrical interference such as AC power lines, radio-frequency generators, and other antennas.

Distance from the Antenna to OMEGA

Determine this distance by checking the signal strength. Start your check with the antenna located as close to the OMEGA unit as possible, using the shortest possible cable length. If you do not get a high-quality connection, try other locations. For example, you might get best results by attaching the antenna to the outside of a building, farther from the OMEGA unit, but with less obstructions between it and the cell site.

Height Above Ground Level of the Antenna

Always elevate the antenna as high as possible, so it has the clearest possible path to the cell site.

Cable for Connecting the Antenna to OMEGA

Lay the connecting cable as straight as possible without kinks, bends, or twists. If you need to keep the cable coiled, use as large a radius for the coil as possible.

Keep in mind that although the maximum distance between the OMEGA unit and the external antenna is 50 feet, the distance between the OMEGA unit and the meter/telephone equipment it serves can be over 1,000 feet. The OMEGA unit does not have to be near the meter/telephone equipment to work. This factor gives you more flexibility in selecting the best antenna location.

When the installation location is within the range of the cell site, a unity gain or 3dB gain antenna is usually sufficient to produce a good quality cellular connection. If the antenna installation is on the fringe of the cell site’s range or outside that range, consider using a high gain directional antenna to achieve an acceptable connection.

If you cannot find an antenna location that results in a good quality connection, you might have to relocate the entire installation. Before doing so, however, try to access a different cell site through the use of a high-gain directional antenna. Even though the new

OMEGA Installation, Operation, and Maintenance Manual

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Contents OMEGA Page Table of Contents Using the Configuration Program Specifying a Default Port Anti-streaming Command Summary Table of Contents Product Overview PrefaceFigure P-1. Omega Application Ancillary Documentation Preface Installation Contents Introduction Hardware FeaturesFinding a Suitable Location Selecting a location for installing OmegaAvoiding Hazards Installing OmegaUnpacking Mounting Omega Required Materials and ToolsMounting an Antenna Mounting OmegaConnecting the Input Voltage Source Connecting an Input Voltage Source Connecting the Endpoint Device LED Powering Up OmegaOperating Omega Call Origination TestingVerifying the Cellular Transceiver Unit Activating Your Cellular TransceiverCall Answer Testing Contents Troubleshooting Contents Checking the Main Power Supply TroubleshootingChecking the Antenna Checking the Battery VoltageReinitializing Omega Specifications Specifications Modem Interface OperationCellular Transceiver Interface Battery OperationPower Supply Switches and LED IndicatorsConnectors Mechanical SpecificationsEnvironmental Specifications EMI/RFI Agency ComplianceSection Specifications Section Using Configuration Program Section Using the Configuration Program Prerequisites Getting Started COM Port Prompt Reading the Cellular Telephone SignalProgramming a Telephone Number Example of Signal BarEntering the Cellular Telephone’s SID Changing the Login PasswordExiting the Configuration Program Section External Antenna Guidelines Section External Antenna Guidelines General Guidelines RF SignalHigh Voltage Areas GainExternal Antenna Selection Criteria Antenna PlacementDistance from the Antenna to the Closest Cell Site Degrees of Down-tilt on the Cell Site Antenna ArrayElectrical Interference Cable for Connecting the Antenna to OmegaDistance from the Antenna to Omega Height Above Ground Level of the AntennaDirectional Antenna Types of External AntennasElevated Feed 3dB Gain Antenna Contact Information Determining the Best External Antenna LocationSection External Antenna Guidelines Appendix a Port Expansion Module Option Appendix a Port Expansion Module Option Field Installation Package ContentsFirgure A-1. Sliding the Module into the Card Guides Figure A-2. Connecting the RJ-11 Jacks Connecting Endpoint Devices Testing the Module PortsTime Delay Method Automatic Connection Second Dial Tone Method Manual Connection Example Atdt 19495552468,,,4 EnterSpecifying a Default Port Anti-streaming To… Do the Following… Command SummaryAppendix B Warranty Compliances Appendix B Warranty & Compliances BWarranty and RMA Statement Limitations FCC Interference Statement FCC StatementFCC Part 15 Statement Comments About This Manual Index Index