Nortel Networks RTU-292 operation manual Alternate Hybrid Test Procedure

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RTU-292 Operations Manual

6.5.2.2 Alternate Hybrid Test Procedure

This alternate test procedure uses a more easily obtainable audio signal generator in place of the noise generator. While this procedure cannot give a complete picture of the unit’s performance in actual use, it will allow a determination of whether or not the RTU-292 is operating properly.

1.Disconnect the RTU-292 from all other equipment and connect the test equipment as shown in Figure 6.1, except use an audio signal generator in place of the noise generator.

2.. Set the PSTN levels for -9 dBm using Option SW2-1, -2, and -3.

3.Start with the following pushbuttons OFF: TEL LINE/PHONE, TEL LINE/RADIO, and TEL VOX. The positions of the other buttons are unimportant. Place the RTU-292 in set-up mode by setting SW2-7 ON and then turning on the power. (See paragraph 2.10.1 for further details about set-up mode.)

4.Adjust the TX Level Adjust, R133, so that the audio voltmeter reads -6dBm (0.387V rms). This sets the transmit signal output path in the RTU-292 for unity gain.

5.Set the output amplitude of the audio signal generator to about 0dBm (0.775V rms). Adjust the RX Level Adjust so that the PEAK LED just comes on. This will set the average noise level into the RTU-292’s hybrid to approximately 0dBm.

6.Remove the unit from Set-up Mode by turning the RTU-292 Main Power OFF, setting SW2-

7OFF, and then turning the main power back ON.

7.Set the audio generator frequency to about 1 kHz.

8.Push the TEL LINE/RADIO button to start the adaptation cycle.

9.When the initial adaptation cycle is complete, the tone output can be read on the audio voltmeter. The voltage should be typically less than -50dBm (2.5mV). The trans-hybrid loss is the difference between this reading and the approximate 0dBm tone level.

NOTE

The reading should be made as soon as the adaptation cycle is complete. The RTU-292 continuously adapts itself to the conditions to which it is exposed. With the single tone input presented by this test, the unit will eventually adapt to reject only this single tone instead of the intended broad range of frequencies. This may take several seconds to several minutes, and an erroneous reading will result when this happens. The reading will always be correct (and an accurate depiction of operation under normal conditions) immediately following the initial adaptation cycle, since the unit has adapted broad band using its own noise source, and has not yet had time to adapt to the single tone only.

10.To measure the unit at a different frequency, change the audio generator frequency and repeat steps 8 and 9.

JPS Communications, Inc.

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Contents JPS Communications, Inc JPS P/N Revision JulyProprietary Statement Phone 919 Fax 919Table of Contents RTU-292 Theory of Operation Front Panel Buttons and Indicators Schematic Diagrams List Of Figures List of Tables Glossary This page intentionally left blank Scope Description GeneralMain Board AssembliesTelephone Interface Power Supply Section Handset/Speaker InterfaceRadio Interface DSP ModuleEquipment and Accessories Supplied Qty Part NumberOptions Optional Equipment Not SuppliedRTU-292 Specifications Unpacking and Inspection GeneralReshipment of Equipment Installation Considerations Installation OverviewFCC Part 68 Regulations 1RTU-292 Factory Default Settings Feature / Function Adjustment Default SettingPower Requirements Input Power SelectionDC Input Power Selection Line Voltage SelectionProgramming Mode Setup Parameters Configuring the RTU-292Setting Telephone Send and Receive Levels Recommended Phone Line Settings Factory default settings are indicated by an asteriskType of System Telephone Send/Receive LevelsVOX Hangtime VOX HangtimeVOX Sensitivity VOX SensitivityDial Mode Dial ModeTelephone Ring Volume RX Line Input ImpedanceRadio Control Mode SW1-3 Radio Control Off Disabled EnabledFull/Half Duplex SW2-8 Full/Half Duplex Off Full DuplexPassword Protection 10Password Protection11Voice Prompts Enable Voice Prompts12Local Phone Enable 14TX Level Set-up ModeInterconnect Information 13 Local Phone RingthroughTelephone Connection 15J1 TEL Line RJ-11CPin Function Radio Connection16P1-RADIO DB-9 Male Handset Connector17J7 Handset RJ12C Jack Terminal Block 18Terminal Block 6 PositionAudio Level Setup and Adjustments 19P2 RS-232 Connector DB-9 MaleSetting the Transmit Level 5 RS-232 ConnectionSetting the Receive Level 10.1.2RTU-292 Operations Manual Outline Dimensions Control and Connector Locations Location Of Internal Option Settings Internal Option Setting Details Audio Interface Wiring Diagram Interface Details Options Installation and Configuration Installation ChecklistInstallation Checklist Front Panel CONTROLS, Indicators and Connectors Speaker Volume Control Phones Volume ControlKeypad TEL Line ButtonsSpeaker Buttons Auto ANS ButtonAudible Ring Button KEY PushbuttonRear Panel Connectors 1 P1 Radio Connector4 J2 Local Phone Connector 7 P1 AC Power ConnectorOperation Operation OverviewUSE of the RTU-292 Speaker to Monitor Audio Placing a Telephone CallUsing the Handset with the Radio Connecting the Radio to the Telephone LineReceiving a Telephone Call Putting a Telephone Call on Hold8.1 Manual Phone Patch Procedure8.2 8.3 8.48.5 8.6Negative Acknowledge Error Remote KEYSelf Test Automated OperationDisconnecting Disconnect Waiting For Input QueryRadio Is Keyed Keyed Radio Is Unkeyed UnkeyedCaller Dials The RTU-292 Caller Enters The Password if enabledRTU-292 Adapts To The Phone Line Placing a Call in the Command Mode RTU-292 Enters the Command ModeTerminating a Call Dtmf Control Commands Operating the RTU-292 from the Front Panel Keypad1Standard Dtmf Operational Commands Dtmf Command Function2Programming Mode Dtmf Commands Inactivity Disconnect Timer RTU-292 Password ProtectionCalling Timer Using the Speed Dial Feature Using the RTU-292 Speed Dial FeatureProgramming the Speed Dial Directory Speed Dial Reset Factory ResetOptional 4 Wire Operation Main Board Front Panel Buttons and IndicatorsAudio BUS Arrangement Telephone Send Circuits Telephone Interface CircuitsTelephone Receive Circuits Ring Detector and Tone Ringer Radio Interface CircuitsReceiver Input Amplifier Transmitter Audio OutputDtmf Detector FSK ModemMicrophone Circuit Speaker and Headphone CircuitsAudio Delay Adaptive HybridNoise Generator Peak DetectorPower Supply AC Power SupplyDC Power Supply 8 CPUOption Interface Board Voice Prompt OptionPrompt Tone Generator Speech ProcessorLocal Phone Option Voice Prompt SoftwareInterface Circuitry DIAL/BUSY GeneratorsRS-232 Remote Control Overview Commands Sent to the RTU-2921Command Summary Auto Answer Command Null CommandAudible Ring Command Date Command Dial CommandDisconnect Command Dtmf CommandHandset Phone Command Handset Radio CommandSpeaker Phone Command Speaker Radio CommandSpeed Dial Command SD nnALL num.? CRTel-Line Phone Command Tel-Line Radio CommandTime Command Software Version CommandStatus Returned from the RTU-292 Response SummaryAuto Answer Response Null ResponseCall Starting Response Disconnect Response Dial ResponseDtmf Response Handset Phone Response Elapsed Time ResponseHandset Radio Response Speaker Phone Response Speaker Radio ResponseTel-Line Phone Response Speed Dial ResponseTel-Line Radio Response Time/Date Response Version ResponseResponse Error Codes Response Error CodesCall Progress Responses from the RTU-292 Call Progress ResponsesPreventive Maintenance Repair or ReplacementPerformance Testing AlignmentHybrid Balance Measurement Hybrid Balance Test Set-Up Main Hybrid Test Procedure Alternate Hybrid Test Procedure VOX Sensitivity Test Set-Up VOX Test Procedure VOX Sensitivity MeasurementFault Analysis Replaceable Parts List DescriptionDescription Reference Designator RTU-292 Operations Manual Reference Designator Special Software Versions RTU-292 OptionsInstallation and Configuration Voice Prompts EnableSW1-6 Voice Prompts Off Disabled Enabled OperationVoice Prompt Option Installation Local Phone Option Installation and Configuration Local Phone EnableSW1-7 Local Phone Off Disabled Enabled SW1-8 Ringthrough Off Disabled Enabled5Local Phone Dtmf Commands Local Phone Option OperationVMM-100 DSP Section VMM-100 HardwareVMM-100 Analog Interface VMM-100 Installation and Configuration VMM-100 SoftwareVMR Algorithm Noise Reduction AlgorithmVMM-100 Option Installation VMM-100 Specifications EnvironmentalVMM-100 I/O Connector Information P9 VMM-100 Switch FunctionsDtmf Access Option After the Call Begins Squelch Break Access Option RTU-292 Prompts for ConfirmationSetting The Time Setting The DateCall Logging Option Checking The Time And DateRadio Control Option Controlling the Radio VIA the RTU-292 Front Panel Keypad9DTMF Radio Control Commands Command Followed By Command DescriptionSchematic Diagrams Blank Index Environmental Self Test Speech Processor
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