Digital Display Interpolation | Fluke PM3370B instruction

HOW TO USE THE INSTRUMENT

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DIGITAL DISPLAY

INTERPOLATION

Interpolation is a mathematical way to calculate displayed dots between actually captured signal samples. Interpolated displays help in the recognition of trace waveforms, even when the number of samples is too low to render an accurate representation of the signal.

Use the bottom key in the DISPLAY menu to control whether or not interpolation is used. You can choose between dots, linear, and sine interpolation.

The default is linear interpolation. Linear interpolation fills the spaces between each sample on the screen with additional dots that are interpolated linearly. This is used to obtain a smoothed display.

-Use the MAGNIFY keys to set the horizontal magnify to *4.

-Turn the X POS control clockwise to display the adc noise only.

The noise is displayed as continuous trace. This is because the space between the samples is interpolated with additional dots and this filled with a continuous line.

LINEAR

DOTS

SINE

ST6736

-Press the bottom softkey to select ’dots’.

Observe that only the sample dots are displayed and the space between the dots is blanked.

-Press the bottom softkey to select ’sine’.

Observe that the trace is smoothed again, but because of a different calculation, it is ’roundedoff’ as compared to the linear interpolation.

Sine interpolation is recommended for signals primarily containing sine waves or combinations.

Image 106

Fluke PM3370B user manual Digital Display Interpolation, Press the bottom softkey to select ’dots’

Contents

Qvwuxphqw Fluke Industrial B.V Reference Manual IIIReference Manual also contains Main Features Page Following parts should be included in the shipment Or model number VII Contents Getting Started -1 3.1 FRONT-PANEL Layout HOW to USE More Advanced FunctionsScreen Controls Auto Setup More Advanced Trigger Functions Contents Contents XII CH2 XiiiCH1 CH3 MOD XIVLine DTB Gate CH1 Y-OUTMain TB Gate Ieee 488.2 BUS Option Operators Safety Safety PrecautionsIntroduction Impaired Safety Protection SymbolsMeasuring Earth Protective earthing Safety InstructionsInstallation Instructions Mains voltage cord, mains voltage range and fuses Rear View Front Cover Installation of batteriesMemory BACK-UP Batteries General information Handle Adjustment and Operating Positions of the Instrument Ieee 488.2/IEC 625 BUS Interface Option Rack Mounting RS-232-C Serial InterfaceVersions FRONT-PANEL Layout Getting Started Switching on the Instrument Screen Controls Screen control area Auto Setup Connect the probe as shown in figure ST5952 Signal Criteria Analog Mode Digital Mode Mode Switching Between Analog and Digital Operating ModesOther Criteria Tude of 2 to 6.4 divi Getting Started Signal Criteria Analog Mode Digital ModeSignal with an ampli Sions Vertical Setup Reconnect the probe to the Probe Adjust signal for display AC Input Coupling Getting Started Timebase Setup Timebase setup Magnify Expand Direct Trigger Setup Direct trigger setup Summary PRE-TRIGGER View More Advanced Features Menu keys and softkeys Cursor Operation Vertical cursors ’’ or the horizontal cursors ’=’ 10 More advanced trigger setup More Advanced Trigger Functions Standard Setup More Signal Detail with the Delayed TimebasePress the Status key and Text OFF key at the same time for MTB1.00ms Ch1 Trace Storage Select Clear & Protect Select Clear ALL Here is how traces are stored in memory Press the Recall key HOW to USE the Instrument PM3394B 200 MHz Full Four Channel Oscilloscope PM3380B 100 MHz 2 Channel Oscilloscope PM3390B 200 MHz 2 Channel OscilloscopePM3384B 100 MHz Full Four-Channel Oscilloscope PM3370B 60 MHz 2 Channel Oscilloscope Front Panel Layout HOW to USE the Instrument Display Adjustment Display and Probe AdjustmentsRecall Standard Setting Simultaneously press the Status and Text OFF keys Display Layout Off T Menus Text OFFPress the Text OFF key three times CAL Signal and Probe Adjustment Repeat this adjustment for the second probe Analog and Digital Modes An amplitude of 2 to Autorange attenuator Not available Results in aDivisions Press the Autoset key for optimum signal display Standard SettingAnalog to Digital Mode Switching Press the Analog key again Trace Storage RUN/STOP 12HOW to USE the InstrumentPress the RUN/STOP key Vertical Deflection Press the AC DC GND key once for DC input coupling 14HOW to USE the InstrumentVertical Coupling AC, DC, GND Press the AC DC GND key to obtain ground coupling Vertical Position Press the AC DC GND key again to obtain ac input coupling Vertical Amplitude 16HOW to USE the InstrumentAdjust Ampl to 100 mV Press the upper key of the Ampl keys Press the Auto Range key Verticalauto RangeVertical Variable Amplitude Press the upper Ampl key once Press the Analog key to return to the analog mode 18HOW to USE the InstrumentPress the Analog key to switch to the Digital mode Vertical CH1+CH2 Vertical Invert Press the ’BW LIMIT’ softkey to turn it on 20HOW to USE the InstrumentVertical Menu Bandwidth Limiter Press the ’BW LIMIT’ softkey to turn it off again Vertical Menu Vertical Probe Range IndicatorRemove the input signal from CH1 Connect the probe again Timebase TIME/DIV Signal is displayed with four periods on the screenHorizontal Deflection and Triggering Set the timebase to 200 μs Display of 2 to 6 waveform periods Timebaseauto RangeTimebase Main TB VAR Press one of the TIME/DIV keys Visible by turning the X POS control 24HOW to USE the InstrumentTimebase Magnify Press the right Magnify key Triggering Timebasex POSTurn the X POS control clockwise Trigger Source 26HOW to USE the InstrumentTriggerslope Trigger Trigger Level Turn the Trigger Level control Trigger Trigger Position Press the Analog key to select the digital modeSet the delay to 0 with Trigger Position Turn the Trigger Position control counterclockwise Trigger Single Shot Digital Acquisition and Storage Advanced Vertical Functions 32HOW to USE the Instrument Acquire Average Acquire Envelope Acquire Peak Detection Advanced Horizontal and Trigger Functions Trigger ModePress the first softkey to select ’tv’ trigger mode Press the Trigger key Press the ’level-pp’ softkey to turn it off Press the TB Mode key Trigger Mode Triggered36HOW to USE the Instrument Move the indicator T- in and out of the signal range Trigger Mode Roll Press the ’STOP on TRIGGER’ softkey to select ’yes’ Slowly vary the frequency of the sine-wave input signal 38HOW to USE the InstrumentTrigger Line Press the ’yes’ confirm softkey Memory FunctionsTrace Storageclear & Protect Press the ’yes’ confirm softkey again Trace Storage Clear 40HOW to USE the InstrumentTrace Storage Save Select memory location ’m1’ Press the ’save’ softkey Trace can be copied from one memory location to another Trace Storage CopyPress the ’COPY’ softkey Turn the POSition control 42HOW to USE the InstrumentTrace Storage Recall Live trace shifts Press the softkey next to ’yes’ Trace Storage Saving Multiple TracesTrace Storage Recalling Multiple Traces Press the Recall menu key Cursors Functions 44HOW to USE the InstrumentTime measurements. These can be done in digital Cursors ON/OFF Cursors Time Cursors Volt 46HOW to USE the InstrumentCursors Amplitude & Time Press the softkey next to ’READOUT’ Cursors ReadoutΔV, V1, V2, ΔV-ratio for voltage measurements 48HOW to USE the Instrument Cursors Readout ΔT-RATIO/PHASEAdjust the cursors to a distance of half a signal period Start with the standard setting.This ensures a correct start Measurement Functions Measure MEAS1-RMS 50HOW to USE the InstrumentMEASUREMEAS1-PKPK Press the second softkey to turn MEAS1 to ’on’ Press the first softkey to select ’delay’ Measure DelayRemove the Probe Adjust signal from channel Measure Meas 2-FREQ 52HOW to USE the Instrument Measure Cursor Limit Procedure to set up for TOUCH, Hold and Measure is Measure TOUCH, Hold & Measure Processing Functions Mathematics Filter Press the softkey next to Math 1 to enter the Math 1 submenu Switch Math 2 off again 56HOW to USE the InstrumentMathematics Multiply Display Functions Analog Display Defl 50Hz Remove the signal from channel Digital Display Use the Track control to adjust Vert Magnify to 60HOW to USE the InstrumentScope ’runs’ once and a signal appears on the screen Digital Display Vert Magnify Press the bottom softkey to select ’dots’ Digital Display InterpolationPress the bottom softkey to select ’sine’ Digital Display Windows 62HOW to USE the InstrumentConnect the Probe Adjust signal to channels 1 Press Autoset Screen displays two or four traces now Delayed Timebase DEL’DTB has two basic functions Delayed TimebaseDelayed Timebase Press the Text OFF button to turn off the menu 64HOW to USE the Instrument Press either key of the Del’dTB TIME/DIV keys Delayed Timebase Trigger Delayed Timebase Trace SEPStart with the Standard Setup Press the softkey to select the TRIG’D mode Press the Trig 1 key in the CH1 section a few times Delayed Timebase Trigger Level Delayed Timebase Coupling Hard Copy Facilities First set the instrument to the standard settingSET Standard To set up the layout of the printer hard copy Utility Print Setup9600, 8, N, 3wire, XON/XOFF=ON Now you are ready to make the hard copy Utility Plot Setup HP7475A, HP7470A, Hpgl = standard HPGL, PM8277 and PM8278 Autoset and Setup Utilities Autoset Standard Autoset User Programmable Setups72HOW to USE the Instrument Position the trace in the bottom of the screen This setup can be saved in memory as follows To recall a previously stored setting 74HOW to USE the Instrument Setup Text LabelSetup Recall a Sequence Autocal Other Features Function Reference Function Reference Acquisition Length Description Memory Expansion Key sequence ADD Invert Subtract Toggle key to switch the inverted display of CH2 CH4 on/offINV Mathematical description ADD MathematicsResult = S1 + S2 Remote commands CPL QW Command to query a waveform Refer to for full details ALT/CHOP Toggle softkey to select ALTernate or CHOPped mode Analog ModeAlternate and chopped modes are shown in the figures below Analog Toggle key to switch between analog mode and digital modeAuto Range Auto Range Autoset CPL AS Command for Auto Setup Refer to for full detailsAutoset Key to start the autoset Autoset Sequence Vert Autoset UserprogUtilityautoset Trig CPL AS Command for an Auto Setup Refer to for full details Autoset Key to switch the Average function on or off Control to select the Average factor Effect of bandwidth limiter Calibration Autocal CPL CL Command for Calibrate Refer to for full detailsCAL CHANNEL/TRACE Selection Power on OFF Confidence Check Cursors Voltage measurements. When CursorsVolt cursors are used for More than one channel is on, Desired channel for voltage Function Reference Cursors Both Track Cursors Readout Time Measured Function Reference Cursors Readout Volt Event delay DelayFull description is given under Delayed Timebase Trigger position CH1 Slope Delay Measurement Delayed Timebase DEL’D TB Function of ’mtb+dtb’, Delay and Trace SEP Delay Digital Mode Toggle switch to switch between analog mode and digital mode Display Menu Interpolation Lines are drawn between sample points Display Text Display of signal with Amplitude variation AM Variation FM or jitter Trig View External Trigger 2 Channels Models onlyAmpl Filter Glitch Trigger Hold OFF Control to adjust Main TB hold off time Using Hold OFF to suppress double triggeringHold OFF Input Attenuator Manual + Automatic Function of key pair AMPL/VAR Auto Toggle key to switch the Auto Range function on/offInput Coupling Range AC/DC/GND Toggle key to switch a channel on/offInput Impedance 200 MHZ Models only AC/DC State Logic Trigger 4 Channels Models onlyPattern Glitch To adjust t2Ift2 Refer to Glitch Trigger function Magnify Horizontal Function of the timebase magnifier and X POS control Function of vertical magnifier and Y POS control Magnify VerticalLeft side decreases the Magnify factor Control to select the vertical magnification Function of key pair TIME/DIV VAR Main Timebase Manual + Automatic46FUNCTION Reference VAR ns Mathematics Measure Menu Volt Following measurements are availablePositive and negative, preshoot positive and negative Multiply Mathematics Result = S1 x S2 Peak Detection Toggle key to switch the peak detection on/off POS Toggle key to switch the oscilloscope on/off Power SupplyPrinting and Plotting Printer or plotter InterfaceLayout Real-time clock Toggle softkey to plot trace information Probe Utilities Control to select the Ieee device address Remote Control IeeeKey to switch from remote to local Status Parity Remote Control RS-232Odd Even LL Inhibits front key Status Local Refer to for full details RUN/STOP Screen controls and function Rise time measurement using the graticuleScreen Controls and Graticule Trace Rotation Always Parity if 7 Bits Auto SettingScreen Messages Autocal Necessary KEY Inactive When Stopped Auto Setting UserprogramCalibration Error No Average in Roll Mode No Event DELAY, Dual Slope No DTB in Roll ModeNo Envelope in Roll Mode No Event Delay in TV Mode STD Setup = Recall only Setup EmptySetup Protected TIME/DIV Adjusted Setups Track Setups Sequence Softkey to recall ’std’ settings Standard Setup / Front Panel ResetStd memory selection Status Screen Subtract Mathematics Subtract mode is available in the digital mode of operationResult = S1 S2 Control to select the Subtract process Timebase Modes Text OFF TRIGGER’ is set to ‘on’, the trace stops when the scope is Flows ‘through’ the screen from left to right. When Roll isSelected, the TB Mode menu provides a ‘STOP on TRIGGER’ Acquired waveform is stored in a different memory location Time Measurements Function Reference Time TOUCH, Hold & Measure Mode Trigger Coupling Ac dc lf-rej Trigger hf-rej Delay Trigger DEL’D TB Toggle softkey to switch DEL’D TB ’on’ Trigger Level control ranges in level-pp on and off Trigger Main TB Slope to change between positive and negative trigger Function of Trigger Level and slopeTrig Toggle key to select CH1, CH.. or Exttrig as Main TB Edge TV Trigger Key sequence Usertext Utility Maintenance Util Menu Utility Screen & Sound Volt Measurements Sn = nth sample j=n=k × S n 100% Oversh OvershootFalling presh = Limit Deflection X-DEFL, X vs Y Toggle softkey to switch X vs Y on Commands CPL Protocol Data Separators AcknowledgeResponses Program data separator Example Program Frame Program frame Commands in Functional Order 4THE CPL Protocol Commands in Alphabetical Order Command Reference Name Command Response Acknowledge ARM Trigger 8THE CPL Protocol Calibrate Default Setup 10THE CPL Protocol GO to Local GO to Remote 12THE CPL Protocol Identification Identity string Example response Local Lockout Xonxoff Program Communication16THE CPL Protocol HWL Approx .5 sec after an acknowledge = 0 is received, Count Node Program Setup18THE CPL Protocol Pds Count Node Pds Program TextChar Char Character Description Examples of user text 22THE CPL Protocol Sample checksum Admin Pds CountProgram Waveform Pds Wavenr Action by Parameter Type Example Oscilloscope Notes Example Example program LSB = Sample and &HFF 26THE CPL Protocol Results is returned cancelling is possible by sending AsciiQuery Measurement Numerical values of an infinite number of measurement T2-trg Value Parameter specified Value,value Or Hz MeasvaluePoint notation, e.g E-09 Example of a single measurement Query Print Null 30THE CPL Protocol Example Written in Quick Basic Count Number of strings to follow Node Query SetupOscilloscope, e.g =10 hex Complete setup query Example response PM3394 Query Text User text is returned Printed, e.g Admin Count Sample Checksum Query Waveform Wavenr The oscilloscope waveform source Parameter Type Example Input #1,NM$ Interpretation of waveform data SettingsSymbol Parameter Value Type Display Sn = Yz + Yn * Yr * Yu DefinitionsFormula’s Sensitivity Time base Time base = 50 * Xr * Xu/div Reset Instrument Pds Setup reg Recall Setup42THE CPL Protocol Save Setup Represents the setup register number, ranging from 1 Status 44THE CPL Protocol Example status Trigger Acquisition 46THE CPL Protocol Synchronization error Ok, normal situation Syntax errorExecution error Acknowledge Status Example program to investigate status Common horizontal settings SetupCommon vertical settings Main Timebase settings Cursor autosearch settings Hex Dec Meaning Events Trigger Delay settingsCursor settings Measurement 1 settings Measurement 2 settings Nnllxxxxxx.......xx Appendix a Acquire menu structure Acquire Menu Structure Appendix B Cursors menu structure Digital Cursors menu structure Appendix C Display menu structured Display Menu Structure Appendix D Mathematics menu structure Mathematics Menu Structure Measure Menu Structure Appendix F DTB DEL’D TB menu structure SAVE/RECALL Menu Structure Appendix H Setups menu structure Setups Menu Structure Appendix J TB Mode menu structure TB Mode Menu Structure Appendix K Trigger menu structure Div T Trigger menu structure Appendix L Utility menu structure Utility menu structure Vert Menu Vertical BW Limit Vertical Menu StructureOn off 50Ω CH1 50Ω CH2 50Ω CH3 50Ω CH4 CTS RS-232 Cable ConfigurationsRTS DTR Cable to printer/plotter with hardware handshake Cable to controller with hardware handshake Appendix P Channels Simultaneously Sampled AT 100 MS/s Channel Acquisitions Expansion and Interpolation Function Index see Chapter Function Index Function Index Index Display and Probe Adjustment Display Functions Display Menu TOUCH, Hold & Measure ModeDelayed Timebase Trigger DEL’D TB Measure Menu Time Measuremens Volt Measurements Util Maintenance Printing and Plotting Remote Control IeeeInstallation Instructions Appendix N Glitch Trigger GND Input Coupling Memory Functions CHANNEL/TRACE Selection SetupsPrinting and Plotting Remote Control RS-232 Memory BACK-UP Batteries Screen Messages Utility Screen & Sound Autoset and Setup Utilities Setups Setups SequenceTimebase Modes Delayed Timebase Timebase Modes Cursors Readout Measure Menu Volt Measurements 8FUNCTION IndexAdvanced Vertical Functions Display Menu Deflection