EFJohnson 7780 service manual Audio Deviation, Data Deviation, Squelch Adjust, Rssi Adjust

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ALIGNMENT PROCEDURE AND PERFORMANCE TESTS

3.Follow the instructions on the screen and adjust for the best demodulated square wave with minimum tilt and overshoot.

6.4 AUDIO DEVIATION

1.If manually selecting each test, click the “Tune” button in the “Audio Deviation” box. Otherwise, this function is selected automatically when the “Complete Tune” button is clicked.

2.Inject a 1 kHz signal at the level indicated on the screen into the Mic Audio jack of the RPI (see Section 6.1.2).

3.Monitor the transmit modulation signal with a communication monitor and follow the instructions on the screen to adjust the wideband, narrow band, and NPSPAC (see Section 1.2.5) deviation.

6.5 DATA DEVIATION

1.If manually selecting each test, click the “Tune” button in the “Data Deviation” box. Otherwise, this function is selected automatically when the “Complete Tune” button is clicked.

2.Monitor the transmit modulation signal with a communication monitor and follow the instructions on the screen to adjust the wideband, narrow band, and SMARTNET/SmartZone control channel data deviation.

6.6 SQUELCH ADJUST

The input level to the noise squelch circuit is set by R13 on the IF board, and the squelch threshold level is set by the PCTune software. The factory setting of R13 should not need to be changed, so step 3

which follows can normally be skipped. Proceed as follows to set the squelch:

1.If manually selecting each test, click the “Tune” button in the “Squelch” box. Otherwise, this func- tion is selected automatically when the “Complete Tune” button is clicked.

2.Connect an RF signal generator to the antenna jack using a 6 dB or greater pad. Set the generator for the channel frequency and modulation indicated on the screen.

3.If R13 must be adjusted (see preceding), remove the transceiver cover and connect power as described in Section 6.1.6. Temporarily set the squelch for “50” on the “Squelch” screen and adjust R13 (see Figure 6-3) so that the squelch just opens (audio is heard) at 8-9 dB SINAD.

4.Readjust the squelch level as indicated on the screen so that the squelch opens and closes between the indicated SINAD levels.

6.7 RSSI ADJUST

NOTE: Improperly setting the RSSI levels can result in degraded SmartZone roaming operation. Therefore, do not change the default settings unless you are familiar with how roaming will be affected.

The function which adjusts the RSSI levels is available only by clicking the “Tune” button in the “RSSI” box. It is not displayed in the Complete Tune mode for the reason just described. The default values that are programmed by clicking the “Program Defaults” button (see Section 6.1.5) should not be changed unless you are familiar with how these levels control site switching in a SmartZone system.

 

November 1999

6-5

Part No. 001-7780-500

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Contents 7780 Page Page Table of Contents Table of Contents CONT’D List of Figures List of TablesScope of Manual Equipment Description General InformationFactory Customer Service AccessoriesPart Number Breakdown Transceiver IdentificationAccessory AccessoriesToll-Free 800 Factory ReturnsReplacement Parts Internet Home Intrinsically Safe InformationDefinitions Possible Ignition Sources Temperature Code T3CIntrinsically Safe and Nonincendive Ratings Classification of Hazardous Areas and AtmospheresMaterial Classification Accessing PC BoardsTypical Hazard Group Class Area ClassificationRemoving Logic Unit Removing RF UnitGeneral SpecificationsFeatures Transceiver OperationControls and Display Low-Battery Indicator Amber TX Indicator Red Indicates when the transmitter is keyedDisplay Front Panel Keys Full Keypad ModelDisplay Option Switches Turning Power on and Setting VolumeGeneral Operation BacklightOption Switch Functions Function ConvSee Scanning Tone ENABLE/DISABLEConventional and SMARTNET/ Smartzone Operation Conventional Features Display Mode SelectionMonitoring Before Transmitting Monitor Mode Busy Channel LockoutCall Guard Squelch Conversation Timer Penalty TimerPower Output Select Conventional Mode ScanningPriority Channel Sampling Standard Conventional Calls DTMF/ANI SignalingViewing Unit ID SMARTNET/SMARTZONE FeaturesStandard Group Calls Enhanced Private Conversation CallsTransceiver Operation Private Conversation II Calls Telephone Calls Call Alert Emergency Alarm and Call MessagingSending Status Conditions Failsoft Operation SMARTNET/SMARTZONE ScanningDynamic Regrouping Supervisory Tones Keypad Programming Menu DescriptionZone Change Parameter Channel Change Parameter System ParametersChannel Parameters Pctrunk Software Installation Programming SetupTransceiver Programming Computer DescriptionStarting and Exiting Connecting RPI to Computer and TransceiverProgramming File Types Help FilesProgramming Procedure Screen Pop-Up Buttons and File Size IndicatorFile Size Indication Creating and Displaying SystemsMenu Bar Menu CommandsDownload Menu Upload Menu Radio Type MenuSystems Menu Window MenuRADIO-WIDE Parameter Screens DefaultsBand ZonesRadio-Wide Scan List Screen Radio Wide Scan ListModify List Screen Assign Function ButtonsRADIO-WIDE SMARTNET/SMARTZONE Screen RADIO-WIDE Conventional ScreenFull Spectrum CC Scan Hot DtmfRADIO-WIDE Portable Options Screen Adjustable ParametersProgramming Conventional Systems and Channels Conventional System General ScreenConventional System Modify Scan List Screen TimersKeypad Editing Scan List ButtonScan Timers Setting UP Conventional ChannelsPriority Channel Selection Selected Channel Conventional Channel Screen ParametersSignaling Transmit PowerChannel Type Tx Time-OutTime-Out Timer Restricted AccessISW Delay Time Splinter ChannelsSMARTNET/SMARTZONE System Phone Interconnect Screen SMARTNET/SMARTZONE System Other ID’S ScreenPhone Interconnect Private CallEmergency Alarm SMARTNET/SMARTZONE System Emergency Settings ScreenSMARTNET/SMARTZONE System Talk Groups Screen Failsoft ChannelSMARTNET/SMARTZONE System Lists Screens Trunking Phone List ScreenMessage Aliasing Screen Control Channels Screen Announcement Groups ScreenTrunking Call List Screen Setting UP SMARTNET/SMART- Zone Channels Status Aliasing ScreenSMARTNET/SMARTZONE Channel Screen Parameters Other Screen Parameters SMARTNET/SmartZone Channel ScreenRecommended Tone Call Guard Codes Freq Call Guard CTCSS/DCS Codes and TonesMHz Channels MHz Channels MHz Channels MHz Channels MHz Channels MHz Channels Power Switching Power Switching and RegulationCircuit Description Synthesizer DescriptionVCO and Tcxo Modulation Synthesizer Chip IC1Charge Pump Q1, Q2, Loop Filter Receiver Circuit Description RF Amplifier Q1, First Mixer Q2If Amplifier Q2, LIMITER/DETECTOR IC3 Squelch Circuit IC4A/B, IC5A Antenna Switch and LOW-PASS FilterTransmitter Description Amplifier Q9, Driver Q8Receive Audio Processing Control Logic and DisplayPin Port Name Input or Description Active High Output Microprocessor IC306 Pin DescriptionsHvfulswlrq Audio Amplifier IC104-IC106 Receive and Transmit Data ProcessingReceive Data FILTER/DETECTOR IC102A/B, IC107A/B Transmit Audio Processing Transmit Data Filter IC206B/ IC206ASmartnet Data Processing LOW-PASS Filter IC205A/BBattery Pack Battery Pack and Charger InformationPower Setting Operating Time Function Fahrenheit CelsiusBattery Pack and Charger Information Test Setup Alignment Procedure and Performance TestsMm/3/32 Mm/1/8 Phone Jack Tune Software HqhudoMain Pctune Screen Preliminary SetupTransmit Power Adjustment Screen Transmit Frequency and PowerHigh Power Level = 3.0 watts Low Power Level = 1.0 watt Modulation BalanceRssi Adjust Squelch AdjustAudio Deviation Data DeviationReceiver Performance Tests Performance TestsTransmitter Performance Tests Power OutputTransmit Frequency Transmit ModulationThis page intentionally left blank Display Assembly Parts ListChassis Parts Ref No DescriptionDisplay Assembly KEY AssemblyIf Assembly KEY AssemblyIf Assembly RF Unit PLL AssemblyRF Unit NJM2904V-TE1 IC RF Unit Logic Unit Logic Unit TDA7233D IC Logic Unit 200K ERJ3GE MP35 MP18 MP25 EP2 KEY Front PanelEP1 MP32 MP33 MP27 MP34 MP28 MP29 MP23 MP22 MP30 MP24 MP26 MP18 Schematic Diagrams and Component Layouts PLL Board TOP ViewPLL Board Bottom View If Board Bottom View If Board TOP ViewRF Unit Transceiver Block DiagramMIC RF Board TOP ViewIf AMP RF Board SchematicHD1 Logic Board TOP ViewReceive Audio Processing Logic Board SchematicGND KEYR3 KEYR2 KEYR1 KEYR0 KEYS3 KEYS2 KEYS1 KEYS0 GND Display Board Bottom ViewDS3 DS4 DS5 Display Board SchematicKEY Board Back View KEY Board Front ViewS S R R R R KEY Board SchematicScan HC2 HC7 HC8 HC3 Schematic Diagrams and Component Layouts
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