Attenuator Assembly Troubleshooting | Agilent Technologies 45A, 46A

Chapter 5: Troubleshooting

To troubleshoot attenuator failures

Attenuator Assembly

Troubleshooting

Perform Connectivity Test on all channels

Set attenuator

contact counter to zero for channels where attenuator assembly replaced

Replace faulty

attenuator assembly

and put good

assembly back in original channel.

			Swap failing channel
			attenuator assembly
Do channels fail?		Yes	attenuator assembly
Do channels fail?		Yes	with known good
			with known good
			assembly.


	No


Perform Click Test on
all channels

Perform Connectivity Test on all channels

Does same

channel fail?

Yes

			Swap failing channel
			attenuator assembly	Perform Click Test on
Do channels fail?		Yes	attenuator assembly	Perform Click Test on
Do channels fail?		Yes	with known good	all channels
			with known good	all channels
			assembly.


	No

Set attenuator

contact counter to

zero

Run Self-Calibration

Go to Attenuator Assembly

Troubleshooting if assemblies

replaced

Does same

assembly fail?

Write attenuator

contact information on attenuator labels of defective assembly

Yes

Exchange or replace acquisition assembly

5–58

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Image 135

Agilent Technologies 45A, 46A, 54835A manual Attenuator Assembly Troubleshooting

Contents

Agilent Model 54835A/45A/46A Oscilloscopes Display shows waveforms and graphical user interface Trigger setup controls set mode and basic parametersService Policy Ease of use with high performance Measurements Power This Book Contents To remove and replace the backlight inverter board ContentsNo Display Trouble Isolation To check the keyboard To check the LEDs To remove and replace the floppy disk drive Replaceable Parts General Information Instruments covered by this service guide Oscilloscopes Covered by this Service GuideModel Description Accessories supplied Accessories supplied Options available Options availableOption Number Description Agilent 1144A MHz Active Probe Accessories availableAccessories available Required when using 2 or more Agilent 1144A active probes Agilent Specifications & characteristics Specifications & characteristicsAcquisition Specifications & characteristics Vertical Post-trigger HorizontalOffset Accuracy Whichever is larger Specifications & characteristics Trigger Measurements Specifications & characteristics Display Computer System/ Storage CAT I and CAT II Definitions Video OutputRise Time figures are calculated from tr=.35/Bandwidth Agilent Technologies 54835A/45A/46A general characteristics Agilent Technologies 54835A/45A/46A general characteristicsGeneral Characteristics Agilent Technologies 54835A/45A/46A general characteristics Agilent EPM Sensor 441A/Agilent 8482A Agilent Service software No substitutionRecommended test equipment Recommended test equipment Preparing for Use Preparing for Use To inspect the instrument To inspect the instrument To connect power To connect powerThree-wire Power Cable is Provided To connect the mouse or other pointing device To attach the optional trackballTo connect the mouse or other pointing device To attach the optional trackball To connect the keyboard To connect to the LAN cardTo connect the keyboard To connect oscilloscope probes To connect oscilloscope probes To connect a printer To connect a printer To connect an external monitor To connect the Gpib cableTo connect an external monitor To tilt the oscilloscope upward for easier viewing To tilt the oscilloscope upward for easier viewing To power on the oscilloscope To power on the oscilloscopeYou Can Configure the Backlight Saver Press the Autoscale key on the front panel Press the Default Setup key on the front panelGraphical Interface Enable Button To verify basic oscilloscope operation To clean the instrument To clean the display monitor contrast filterTo clean the instrument Testing Performance See Also Test Interval Dependencies Let the Instrument Warm Up Before Testing Clear DisplayAveraging Connect the multimeter to the front panel Aux Out BNC Enable the graphical interfaceProcedure To test the dc calibrator If the test fails Set Aux Output to DC Set the output voltageSelecting DC in the Calibration Dialog 25% accuracy Cables Input Resistance Equipment SetupTo test input resistance To test input resistance To test voltage measurement accuracy SpecificationTo test voltage measurement accuracy Connect the equipment Voltage Measurement Accuracy Equipment Setup Acquisition Setup for Voltage Accuracy MeasurementUse the following table for steps 8 through Scale Offset Supply Tolerance Limits Select Channel 1 as the source for the Vavg measurementSource Selection for Vavg Measurement Set the scale from the table Set the offset from the table To Set Vertical Scale and Position Volts/div Position Supply Tolerance Limits To test offset accuracyUse the following table for steps 6 through To test offset accuracy To test offset accuracy Equivalent Time Test Specification Equivalent TimeTo test bandwidth Real Time Calculate the response using the formula Select Vamptd from the Voltage submenu of the Measure menuDisplayed. Note the Vamptd1 reading MΩ, 500 MHz Test on 54835A, 54845A, and 54846A Real Time Test Equivalent Time ≥16 averages Equivalent Time Mode ProcedureTo test time measurement accuracy To test time measurement accuracy Waveform for Time Measurement Accuracy Check Horizontal Setup for Equivalent Time Procedure Source Selection for Delta Time Measurement Acquisition Setup for Equivalent Time Procedure For valid statistical data Measurement Settings for Time Interval Measurement New Measurement Settings for Delta Time Measurement Measurement Definitions for Real Mode Procedure Real-Time Mode Procedure Click Close To test trigger sensitivity Acquisition Setup for Trigger Sensitivity TestTo test trigger sensitivity Set horizontal time/div to 5 ns/div Turn on Channel 1 and turn off all other channels Setting the Markers for a 0.5 Division Reference If a test fails Procedure-Auxiliary Trigger TestPage Voltage Scale Coupling Supply Limits Channel Agilent Technologies 54835A/45A/46A OscilloscopeTest Limits Results Vmax Vmin/5 = Amplitude Input Channel Chan 4/Ext Resistance ∆Time edge#101 Limits Realtime Channel 4 GSa/sChannel 8 GSa/s Channel 2 GSa/s Calibrating and Adjusting Calibrating and Adjusting Loading New Software Let the Oscilloscope Warm Up Before Adjusting Equipment Critical Specifications Recommended Model/Part To check the power supplyDisconnect the oscilloscope power cord and remove the cover To check the power supply Supply Voltage Specification Limits Power Supply Voltage Limits Equipment Required To check the flat panel display FPD Flat-Panel Display SpecificationsWhen to Use this Procedure To check the flat panel display FPD Starting the Screen Test Click Start Screen Test Repeat steps 6 and 7 for all colors Calibration time To run the self calibrationTo run the self calibration Self calibration Click here to start calibration Click Start, then follow the instructions on the screenClear Cal Memory Protect to Run self calibration If calibration failsPage Troubleshooting Troubleshooting Installing the Fan Safety Shield To install the fan safety shieldDisconnect the instrument power cord and remove the cover To install the fan safety shield To troubleshoot the instrument To troubleshoot the instrument Primary Trouble Isolation Primary Trouble Isolation Flowchart Check the display Perform power-upPower-on Display Default Graphical Interface Disabled Primary Trouble Isolation Run oscilloscope self-tests Check the front panelRun the Knob and Key selftest and the LED selftest No Display Trouble Isolation Flowchart Sequence Remove the cabinet and install the fan safety shieldNo Display Trouble Isolation Check the fan connections Configure the motherboard Power-onPower supply indicator Isolation flowchart Completed its power-on test LEDs do not come on, Board video signals Power to the instrument.Solenoids are preset Normal operating pattern Not, the problem may be with Power Supply Trouble Isolation Flowchart Approximate Resistance Values, Each Power Supply to Ground Power Supply Trouble IsolationCheck the power supply voltages Power Supply Trouble Isolation Power-up Sense Resistor Connection Replace any shorted assemblyOverride the Remote Inhibit signal Power Supply Distribution Check for the oscilloscope display onscreen Replace the power supplyRouting of +15 V Bias and Remote Inhibit Signals Check +15 V Bias and Remote Inhibit cabling To check probe power outputs To check probe power outputsPin Supply +3V Offset Data Probe ID Ring Clk +12 To check the keyboard When you are finished, click CloseTest Procedure To check the keyboard Re-assemble the instrument Troubleshooting Procedure LED Test Screen To check the LEDsTo check the LEDs Test by Rows When you are finished, click Close To check the motherboard, CPU, and RAM To check the motherboard, CPU, and RAMMessages Vary Slightly Video Signals To check the Svga display board video signalsTo check the Svga display board video signals Signal Backlight OFF Backlight on To check the backlight inverter voltagesTo check the backlight inverter voltages Backlight Inverter Board Input Voltages Input Pin # Checkpoint Code Description Post Code Listing AMI Motherboard onlyPost Code Listing AMI Motherboard only Post Code Listing Next Keyboard BAT command is issuedUnblocking command Color settings next 2Fh Clearing the memory below 1 MB for the soft reset next2Eh Display memory read/write test next After Winbios Setup next Keyboard reset command nextCommand next Winbios Setup next 9Dh 9BhCoprocessor text next 9Ch To configure the motherboard jumpers and set up the Bios To configure the motherboard jumpers and set up the BiosMotherboard / floppy drive configurations Bios setup To configure the motherboard jumpers and set up the Bios To configure the motherboard jumpers and set up the Bios Agilent Technologies Service Note Describes Upgrade Details Series 727 Motherboard Jumpers Configuring the AMI Series 727 Motherboard JumpersJ46 J37, J39 MHz Clock Is Required J2J21 J11 J12J25J24 J37 To configure the AMI Series 727 Winbios Parameters Press F1 to run the Winbios setup Do steps h-l only if Your System has 64 Mb RAM Do the following within the setup programWinbios Keyboard Commands System Keyboard Absent Primary Exit the Setup program, saving the changes you madeConfiguration Item Setting Load Optimal Defaults Series 757 Rev C Motherboard Jumpers Configuring the AMI Series 757 Motherboard for 200 MHz CPU Pin Do not Press F2 When to Do this Procedure Series 757 System Bios Settings with 1.44 Mbyte floppy drive Series 757 Rev D Motherboard Jumpers Configuring the AMI Series 757 Motherboard for 300 MHz CPU J14 J16 AMI Atlas-III PCI/ISA Do the following within the setup program Series 757 System Bios Settings with 120 Mbyte floppy drive Ratio S2-1 S2-2 FIC VA-503A MotherboardCore S1-1 S1-2 S1-3 S1-4 Off Under the PnP/PCI Configuration, change these settings Under the Power Management Setup, change these settings To troubleshoot the acquisition system Under Integrated Peripherals, change these settingsIsolating Acquisition Problems To troubleshoot the acquisition system Acquisition Trouble Isolation 1 Acquisition Trouble Isolation 2 Acquisition Trouble Isolation 3 To D Converter Failed Return the Known Good Attenuator to Original ChannelAcquisition Trouble Isolation 4 Offset DAC failed Temperature Sense failedFiso failed Probe Board failed Timebase failed Scroll Mode Counter failedTimer failed Interpolator failed To troubleshoot attenuator failures To troubleshoot attenuator failuresAttenuator Click Test Repeat steps 1 through 3 for the remaining input channels Swapping AttenuatorsAttenuator Connectivity Test Attenuator Assembly Troubleshooting Software Revisions Enable the Graphical InterfaceSoftware Revisions Select About Infiniium... from the Help MenuPage Replacing Assemblies Replacing Assemblies To return the instrument to Agilent Technologies for service Remove all accessories from the instrument To remove and replace the cover To remove and replace the coverCover Fasteners To reconnect the cable To disconnect and connect Mylar flex cablesTo disconnect and connect Mylar flex cables To disconnect the cable Disconnecting W13 To remove and replace the AutoProbe assemblyDisconnect the power cable and remove the cover To remove and replace the AutoProbe assembly Pushing Out the AutoProbe Faceplate Avoid Damage to the Ribbon Cable and Faceplate Avoid Interference with the Fan To remove and replace the probe power and control assemblyTo remove and replace the probe power and control assembly Removing the Probe Power and Control Assembly Removing the Backlight Inverter Board To remove and replace the front panel assemblyTo remove and replace the backlight inverter board To remove and replace the backlight inverter board To remove and replace the front panel assembly SMB Cable W18 and Comp Wire W19Removing the BNC Nuts Front Panel Side Screws Disconnecting W16, W20, and the Backlight Cables Front Panel Cover Plate Screws Keep Long Screws Separate for Re-assembly Removing the backlights Removing the Cursor Keyboard To remove and replace the acquisition board assembly To remove and replace the acquisition board assemblyRemoving the Acquisition Assembly Removing the LAN Interface Board To replace the board, reverse the removal procedureTo remove and replace the LAN interface board To remove and replace the LAN interface board To remove and replace the Gpib interface board To remove and replace the Gpib interface boardRemoving the Gpib Interface Board Removing the Scope Interface and Svga Display Boards Disconnect these cables from the Svga display board To separate the scope interface board and Svga display board To separate the scope interface board and Svga display board To replace the card, reverse the removal procedure To remove and replace the Option 200 sound cardTo remove and replace the Option 200 sound card To remove and replace the hard disk drive To remove and replace the hard disk driveRemoving the Hard Disk Drive Removing the Floppy Disk Drive Screws To remove and replace the floppy disk driveTo remove and replace the motherboard To remove and replace the floppy disk drive Disconnect these cables from the motherboard To remove and replace the motherboardRemoving the Motherboard Torx Screws To remove and replace the motherboard To remove and replace the power supply To remove and replace the power supplyRemoving Power Supply Cables Removing Fan Fasteners To install the fan, reverse this procedureTo remove and replace the fan To remove and replace the fan To remove and replace the CPU To remove and replace the CPURemoving the CPU Removing RAM SIMMs To remove and replace RAM SIMMs or Sdram DIMMsTo remove and replace RAM SIMMs or Sdram DIMMs Removing and replacing SIMMs on the AMI motherboard To remove and replace an attenuator To remove and replace an attenuatorDo Not Remove the Attenuators from the Acquisition Board Removing an Attenuator If You Permanently Replace Parts To reset the attenuator contact counter To reset the attenuator contact counterSelf Test Attenuator Relay Actuations Setup Attenuator Channel box, select the channel you are changingRepeat for each channel you need to change To remove and replace an acquisition hybrid To remove and replace an acquisition hybridTo remove the acquisition hybrid Do not USE Excessive Force To replace the acquisition hybrid Removing the Hybrid Connector Hybrid Connector Replaceable Parts Direct Mail Order System Ordering Replaceable PartsListed Parts Unlisted Parts Power Cables and Plug Configurations Power Cables and Plug ConfigurationsPlug Type Cable Plug Description Length Color Country In/cm Front Frame and Front Panel Exploded ViewsExploded Views MP61 MP17 MP62 or MP63 MP15 and MP49 Fan and Acquisition Assembly Power Supply and PC Motherboard A10 MP57H12 H24 H25 MP55 MP60 H11 Exploded Views A4A1W24/25 A4A4 Exploded Views Exploded Views FIC VA-503A Motherboard for PC Motherboard Configuration W17W20 A15 W14 W11 A19 W16 A14 W24/25 W27 W22 A4A1H23 A4A2 Exploded Views H10 MP20 MP13 H19 H26 MP19 Sleeve and Accessory PouchMP14 MP52 MP70 MP72 MP12 Attenuator Assembly Replaceable Parts List Replaceable Parts List QTY Agilent Part Des Number DRAM-SIMM 2MX32 8 MB Simm DRAM-DIMM 16MX32 64 MB Dimm Fans Cables Display BD. Jumper Page Theory of Operation Theory of Operation Power Supply Assembly FPD Monitor AssemblyBlock-Level Theory Attenuators Acquisition SystemFront Panel Disk Drives Probe Power and Control Svga Display CardGpib Interface Card Acquisition Block Diagram Acquisition Board Attenuator TheoryAcquisition Theory Attenuator Theory Acquisition Theory Scope Interface Board Acquisition ModesPage Manufacturer’s Name Manufacturer’s AddressSupplementary Information Product Regulations Restricted Rights Legend Product Warranty