Tektronix WFM 601i User Manual Download Page 28

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Installation

1–10

Rev May 1994

WFM 601i Serial Component Monitor

Rear View

18.970

5.250

17.270

6.875

Mounting

Holes

CONTROLS

FRONT PANEL

TO RACK

ALIGNMENT.

Figure 1-4: The 1700F05 side-by-side rack adapter.

The rack adapter is adjustable, so that the WFM 601i can be more closely aligned
with other equipment in the rack. See Figure 1-4.

1700F05

1700F06

Figure 1-5: Instrument in 1700F05 with blank front-panel (1700F06).

Summary of Contents for WFM 601i

Page 1: ...User Manual WFM 601i Serial Digital Component Monitor 070 8966 01 Please check for change information at the rear of this manual First Printing May 1994 Revised November 1995...

Page 2: ...708 Cable TEKWSGT Tektronix Television Division participates in the Broadcast Professionals Forum BPFORUM on the CompuServe Information Service Press releases on new products product specific newslett...

Page 3: ...warranty shall not apply to any defect failure or damage caused by improper use or improper or inadequate maintenance and care Tektronix shall not be obligated to furnish service under this warranty a...

Page 4: ......

Page 5: ...he Official Journal of the European Communities EN 50081 1 Emissions EN 55022 Class B Radiated and Conducted Emissions EN 50082 1 Immunity IEC 801 2 Electrostatic Discharge Immunity IEC 801 3 RF Elect...

Page 6: ...INE FIELD MAG REF EXT SERIAL COMPONENT MONITOR PICTURE VERT POS HORIZ POS MENU VECTOR BOWTIE SERIAL A DISPLAY MULTIPLE VIDEO IN SERIAL ALARM SERIAL B CH3 CH1 CH2 PARADE CLEAR 7 6 8 5 4 3 2 1 1 2 3 Tek...

Page 7: ...i in a Serial Video System 1 14 Functional Check 1 17 Required Equipment 1 17 Initial Equipment Connections 1 18 Procedure 1 18 Operating Basics At A Glance 2 1 Front Panel Controls and Indicators 2 1...

Page 8: ...Lightning Display 3 21 Diamond Display 3 23 Bowtie Display 3 24 Appendices Appendix A Specifications A 1 Appendix B Multipin Connectors B 1 REMOTE Connector B 1 RS232 Connector B 3 Appendix C User Se...

Page 9: ...0 Figure 1 14 Parade display of Y and PB 1 21 Figure 1 15 Parade display of Y PB and PR 1 21 Figure 1 16 WFM 601i on screen RGB display 1 22 Figure 1 17 WFM601i calibrator display 1 23 Figure 1 18 Cal...

Page 10: ...for the Diamond display 3 4 Figure 3 5 Measuring a source 3 5 Figure 3 6 Measuring 20 80 risetime using cursors 3 7 Figure 3 7 Connection for point to point error measurements 3 12 Figure 3 8 Constru...

Page 11: ...Eye Pattern Display A 3 Table A 5 Video Error Detection and Diagnostics A 4 Table A 6 External Reference A 4 Table A 7 Waveform Horizontal Deflection A 5 Table A 8 Calibrator A 5 Table A 9 Component V...

Page 12: ...Contents vi WFM 601i Serial Component Monitor...

Page 13: ...terminal ATTENTION Refer to manual Specific Precautions This product is intended to operate from a power source that will apply no more than 250 V rms between the supply conductors or between either...

Page 14: ...er fuse replacement to qualified service personnel To avoid explosion do not operate this product in an explosive atmosphere To avoid personal injury do not remove the product covers or panels Do not...

Page 15: ...mation needed for daily operation It has At a Glance which describes the controls and connectors and Functional Over view which discusses operation of the instrument Reference provides detailed descri...

Page 16: ...Preface x WFM 601i Serial Component Monitor...

Page 17: ...Getting Started...

Page 18: ......

Page 19: ...rement three selectable bandwidths H Serial Format Checking H EDH Follows A B switching LED for presence and an alarm rear panel TTL low through Remote Connector H RGB or Y PB PR display format H Any...

Page 20: ...ll up to 10 front panel setups through the Preset menu 9 presets are user programmable and 1 is factory programmed Vertical and horizontal instrument gain can be set using the calibrator signal The ca...

Page 21: ...ithin the instrument to dissipate 1700F02 Carrying Case This portable cabinet is similar to the 1700F00 but has feet a carrying handle flipstand and front cover 1700F05 Side by Side Rack Adapter The 1...

Page 22: ...rd and one replacement fuse Power cords for use in North America are UL listed and CSA certified Cords for use in areas other than North America are approved by at least one test house acceptable in t...

Page 23: ...in the original packaging materials If the original packaging materials are not available follow these directions a Obtain a carton of corrugated cardboard having inside dimensions six or more inches...

Page 24: ...to 300 MHz Qty 2 Internal Jumper Jumper J6 changes the rear panel Serial Out signal amplitude Normal Output amplitude is 800 mV but some equipment may work best at 740 mV Jumper J6 located on the Dese...

Page 25: ...t vent holes Operation in air flow restricted environments may lead to excessive heat build up All qualification testing for the WFM 601i was performed in a 1700F00 cabinet To guarantee compliance wit...

Page 26: ...s contact your nearest Tektronix field office or representative for assistance in ordering 5 000 1 625 Rear Bottom Side 9 435 6 875 8 250 0 688 5 105 3 310 16 180 0 141 Diameter 4 Figure 1 2 1700F02 p...

Page 27: ...ed to the cabinet by two 6 32 Pozidriver screws located in the upper corners of the rear panel See Figure 1 3 Cabinet Mounting Screws Figure 1 3 Rear view of the WFM 601i The optional 1700F05 side by...

Page 28: ...ing Holes CONTROLS FRONT PANEL TO RACK ALIGNMENT Figure 1 4 The 1700F05 side by side rack adapter The rack adapter is adjustable so that the WFM 601i can be more closely aligned with other equipment i...

Page 29: ...ve When only one instrument is mounted in the side by side adaptor an accessory drawer 1700F07 can be installed in the blank side of the cabinet See Figure 1 6 1700F07 1700F05 Figure 1 6 1700F05 cabin...

Page 30: ...Figure 1 7 Requires four 0 156 holes below the 1700F00 cabinet to secure the instrument to the shelf For Flush Front Panel Cut hole the same size as the monitor front molding to allow the monitor fro...

Page 31: ...safe operation WARNING When power is supplied line voltage will be present in the instrument even if the POWER switch is set to STANDBY The WFM601i monitors operate at 50 and 60 Hz over the range of...

Page 32: ...gnal through one of the loop though inputs while connecting the output of the device to the other loop through for either further distribution or termination allows a check of both the incoming signal...

Page 33: ...le between it and the loop through serves as the termination This is the preferred monitoring connection because the performance of the entire serial path can be inspected The return loss of the WFM 6...

Page 34: ...ss terminator and Figure 1 11 shows the eye pattern of a terminator having only 13 dB return loss at 100 MHz capacitive Terminations causing aberrations of under 10 should be acceptable Figure 1 10 Ey...

Page 35: ...cedure are representations of actual displays on the WFM601i If performing the Functional Check reveals improper operation or instrument malfunction first check the operation of the associated equipme...

Page 36: ...tting by turning the front panel bezel knob under the list of presets until FACTORY is highlighted Press the bezel button adjacent to RECALL The PRESET MENU is automatically exited and the front panel...

Page 37: ...at a comfortable yet visible setting If the readout intensity is accidently turned too low to see consult the CRT Menu discussion on page 2 21 for the recovery procedure Press the top bezel button ag...

Page 38: ...om OVERLAY to 10 EYE Press the CONFIG button Use the second from the left bezel knob to change the submenu to the EYE PATTERN menu Push the button adjacent to the menu selection for DISPLAY second fro...

Page 39: ...r lights Press the CH 2 button and check that both the CH 1 luminance signal and the CH 2 PB signal are displayed See Figure 1 14 7 6 8 5 4 3 2 1 1 2 3 Tek COMPONENT ANALOG 2 4 KPB 100 50 Figure 1 14...

Page 40: ...rn to the YPBPR setting for WFM AS Push the CLEAR MENU button 7 6 8 5 4 3 2 1 1 2 3 Tek COMPONENT ANALOG 2 4 KPB 100 50 Figure 1 16 WFM 601i on screen RGB display 6 Check Gain The WFM 601i has an inte...

Page 41: ...er two assignable bezel controls are now labeled V CAL and H CAL Rotate both controls enough to see that the horizontal and vertical gains have changed noticeably and that two new labels have appeared...

Page 42: ...ss the bezel button corresponding to X10 Check that X10 is highlighted and that the display is immediately amplified again Press the bezel button adjacent to the VARIABLE ON OFF menu selection Check t...

Page 43: ...approximately 25X 7 6 8 5 4 3 2 1 1 2 3 Tek COMPONENT ANALOG 2 4 KPB 100 50 Figure 1 19 One field display of CH 1 Y signal Press the LINE FIELD button Check that the FIELD indicator lights and that th...

Page 44: ...s filter LPASS or a differentiated step DIFF filter for the waveform display The normal display is unfiltered Press the FILTER button to enter the filter menu Check that FLAT is highlighted Change the...

Page 45: ...displays ALL 150 Note that there is no NEXT FIELD label In the 2 LINE display the left display is line 150 and the right display is line 151 Press the bezel button adjacent to ALL 1 OF 2 to highlight...

Page 46: ...d portion of each field increases in width See Figure 1 24 Note that the line select readout now reads the selected line range F1 150 164 if you are in the first field 1H 15H FIELD ALL 1OF2 2 7 6 8 5...

Page 47: ...tor to the vectorscope display mode The display should look similar to Figure 1 25 Press the CONFIG button to enter the CONFIGURATION menu Rotate the menu selection control until WFM VEC is high light...

Page 48: ...veform as chosen from the configuration menu The DIAMOND display shows the relationship of R G and B color components and is primarily used to verify RGB Gamut The LIGHTNING display shows the relation...

Page 49: ...component color difference signals 15 Diamond Display Press the CONFIG button to enter the CONFIGURATION menu In the WFM VEC submenu press the bezel button corresponding to LIGHTNING DIAMOND DISPLAY C...

Page 50: ...splay of component signals the first line displays CH 1 minus CH 2 the second line displays CH 1 minus CH 3 Select the timing signal from the Digital Component Generator Make sure it is the low freque...

Page 51: ...Operating Basics...

Page 52: ......

Page 53: ...SERIAL B CH3 CH1 CH2 PARADE CLEAR 7 6 8 5 4 3 2 1 1 2 3 Tek COMPONENT ANALOG 2 4 KPB 100 50 EYE EQ EYE Figure 2 1 WFM601i front panel Front Panel Controls and Indicators Bezel Knobs The center three...

Page 54: ...waveform vector or lightning parade vector or lightning VIDEO IN These three buttons turn on or off CH 1 Y R CH 2 PB G and CH 3 PR B At least one channel is always on SERIAL A SERIAL B Selects the sig...

Page 55: ...enu selections Two front panel indicators show the characteristics of the incoming video When the serial input signal has the Error Detection and Handling EDH signal embedded in it the EDH Detection l...

Page 56: ...01i if it is not enclosed in a prescribed cabinet Dangerous potentials are present on the Power circuit board REMOTE RS232 1 1 13 14 25 5 6 9 1 5A MAX 90 250V 50 60 HZ R Y G PB B PR R SERIAL EXT REF W...

Page 57: ...or display This gamut error bright up signal is present on the Y or G and can be turned off by menu selection SERIAL OUT Reclocked serial output of selected signal input SER A or SER B RS232 A 9 pin s...

Page 58: ...At A Glance 2 6 WFM 601i Serial Component Monitor...

Page 59: ...input can be displayed in one or two line or one or two field sweeps In Line Select mode identified lines of any field can be selected and displayed Time and Voltage cursors can be activated and posi...

Page 60: ...and Y and PR Ch 1 and 3 In Bowtie mode the left half of the display shows Channel 1 minus Channel 2 and the right half shows Channel 1 minus Channel 3 If the timing between channels is matched the ce...

Page 61: ...ctor box to the EYE PATTERN menu selection Pressing the bezel button adjacent to DISPLAY will cause the trigger mode to toggle between OVERLAY and 10 EYE OVERLAY In OVERLAY all of the bits of a serial...

Page 62: ...E EYE PATTERN menu Each filter will suppress jitter terms below the indicated 3 dB point allowing medium and high frequency jitter to be separated from low frequency jitter The 10 Hz and 1 KHz filters...

Page 63: ...ntrol Both amplitude and time cursors are available via the CURSOR menu The EYE PATTERN displays can be windowed around specific segments of the video frame by using the line selector Both 1H and 15H...

Page 64: ...tion with a fixed pattern source when incoming EDH is not available Finally the elapsed time since the errored seconds readouts were last cleared via the RESET soft key is shown This particular screen...

Page 65: ...ts a no signal condition the STATUS screen indicates SIGNAL MISSING Under this condition the line rate and active bits readouts are blanked See figure 2 7 In Figure 2 7 loss of signal condition is ind...

Page 66: ...8 Basic FORMAT Screen DATA RANGE Indicates an error if the reserved values of 000h 003h or 3FCh 3FFh are used incorrectly SAV PLACEMENT Indicates an error if SAV is improperly placed with respect to...

Page 67: ...both the menu readout and in the case of Line Select Cursor Filter and Gain disables the function When selecting Line Select Cursor Filter or Gain the last settings are returned For example if X5 and...

Page 68: ...h Mark 2 is double dash Mark 3 is the shortest dash The markers have no readout associated with them CLEAR MENU removes the readout associated with the cursor selection but the cursors difference read...

Page 69: ...o turn off the function push the LINE SEL menu button when the menu readout is displayed two pushes of the LINE SEL button if the menu readout is not displayed The Preset menu makes it possible to rec...

Page 70: ...and Preset 8 has now been selected but not recalled Pushing RECOVER returns to Preset 1 To restore the Preset menu push the PRESET menu button again To turn off the function Recall a Preset press CLEA...

Page 71: ...converters and subsequently to the display and the picture monitor output In Pass mode all digital data is sent to the converters EYE PATTERN Selection choices for the EYE and EQ EYE display modes DIS...

Page 72: ...i MONITOR OUT AS Configures the analog component picture monitor out signal as either Y Pb Pr YPBPR or as GBR GBR Composite sync is added to the Y or G channel STANDARD Selects the scanning standard t...

Page 73: ...al gain equally Lightning and Diamond displays have both horizontal and vertical variable gain CLEAR MENU turns off all of the menu readout except the VAR GAIN label if turned on Variable gain remains...

Page 74: ...15 outputs an active low TTL pulse during selected lines when in Line Select modes This signal can be used as a logic analyzer trigger Pin 16 outputs an active low TTL level whenever the front panel A...

Page 75: ...there should be one half cycle per major graticule division in 2 LINE SWEEP 10 s div there should be one full cycle per major division b If the RESET H CAL readout is on push the adjacent bezel butto...

Page 76: ...Functional Overview 2 24 WFM 601i Serial Component Monitor...

Page 77: ...Reference...

Page 78: ......

Page 79: ...See Page 3 3 for a discussion of the electronic graticules This is the graticule that is permanently etched on the CRT faceplate glass It has controlled illumination which varies between off and a lev...

Page 80: ...the left or right from the leading or trailing edge 2T pulse to bar measurements are made using the solid and dashed lines located to the left of K Factor box These lines are scaled according to the...

Page 81: ...owards the color point which corresponds to 75 or 100 amplitude for the color being measured Figure 3 2 Vectorscope graticule On the WFM 601i electronic component vectorscope graticule each chrominanc...

Page 82: ...he RGB signal is either within or outside valid gamut limits Signals contained within the diamonds are within gamut limits The two identical diamonds are used to convey amplitude errors Errors in gree...

Page 83: ...ations have established specifications for these three components Many of the specifications describe the acceptable output waveform from a serial source These include signal amplitude aberrations ris...

Page 84: ...proper amplitude is important Serial sources should produce good signal transitions with a minimum of overshoot and ringing Otherwise automatic equalizer circuits in receivers may not perform properly...

Page 85: ...isetime of 500 ps This finite risetime must be considered when determining the actual risetime of the source being measured The actual risetime of the source being measured can be calculated using the...

Page 86: ...se distortion and variations in bit patterns all combine to cause jitter Jitter results in eye closure along the time axis narrowing the window in which the data values can be accurately determined Da...

Page 87: ...cification has created some confusion and is currently under review Many experts favor a revised specification where jitter is measured over specified frequency bands This is the approach taken by the...

Page 88: ...es the serial signal as the step generator and the WFM 601i as the bridging sampler Connect a serial source having low aberrations to one of the WFM 601i serial inputs Place a high return loss 25 dB t...

Page 89: ...channel the signal is being inspected For measurements directly on the output of sources or with only short lengths of cable EYE mode is recommended In this mode the serial signal as it appears at the...

Page 90: ...and 318 If the source does not insert EDH an alternate source such as the Tektronix TSG 422 option 1S generator can be used This substitution is allowed because the output waveforms of sources are sta...

Page 91: ...error rate measurement capability to virtually any point in a facility Strategic placement of these monitors can help keep track of a plant s performance Similarly a single EDH error monitoring instr...

Page 92: ...mple a manufacturer could specify the expected CRC values for various operating modes with a given test signal Any disagreement may indicate a problem This is analogous to signature analysis that is s...

Page 93: ...own as the pathological signal can contain a large low frequency component Serial equipment with inadequate coupling time constants may not properly pass this signal without errors Sweeping the eye pa...

Page 94: ...color video signals are coded to RGB for display on a picture monitor To be predictably displayed all three components must lie between peak white normally 700 mV and black normally 0 V Excursions out...

Page 95: ...ial Component Monitor 3 17 0 V 700 mV 700 mV Legal G and B space 700 mV 0 V 700 mV Green X Y plot Rotated 45 degrees Green Red Blue B R G G Origins moved together B R G G Legal G and R space Figure 3...

Page 96: ...rrection When an out of gamut condition exists that requires correction the Diamond display can aid in determining which component R G or B is out and in which direction By remembering that Diamond is...

Page 97: ...as amplitude risetime and jitter as well as to identify signal distortions such as those caused by transmission channel reflections The WFM 601i uses an equivalent time sampler to create the eye patt...

Page 98: ...se these timing differences include the delay in the decoder output filtering they are largely ignored unless they become too gross In the component domain there is no decoding required and therefore...

Page 99: ...nals are line alternated and the luminance signal inverted on alternate lines The B Y PB signal is applied concurrently with the positive luminance signal Y the R Y PR signal is then applied with the...

Page 100: ...waveform or parade display modes of the monitor Interchannel Timing The scale between the green and magenta targets is used to check interchannel timing CH 2 to CH 1 and CH 3 to CH 1 or signal delay I...

Page 101: ...cal axis and R G on the horizontal axis The resulting display is the vertices of two diamonds which form the RGB gamut limits See Figure 3 13 The graticule used with this display has no targets or spe...

Page 102: ...n 1S provides this type of signal and a set of time marks to aid in signal evaluation The signal is a 500 kHz sinewave on channel 1 luminance and 502 kHz sinewave on channels 2 and 3 color difference...

Page 103: ...If the null is to the left of the center marker luminance is delayed When either of the nulls is shifted to the right that color difference signal is delayed when compared to luminance channel timing...

Page 104: ...Measurement Theory 3 26 WFM 601i Serial Component Monitor...

Page 105: ...Appendices...

Page 106: ......

Page 107: ...uipment Required list These instruments are intended to operate from an ac power source that will not apply more than 250 V rms between the supply conductors or either supply conductor and ground A pr...

Page 108: ...able A 2 Serial Digital Video Interface SER A SER B Characteristic Performance Requirement Reference Information Format 270 Mbit s component Complies with SMPTE 259M CCIR 656 Input Type Passive loop t...

Page 109: ...1 dB Low frequency 3 dB point is 500 Hz Rise Time 500 ps 20 80 775 ps 10 90 Aberrations 10 800 mV Step Time Base Jitter 200 ps peak to peak Jitter Attenuation 10 Hz HPF 100 Hz HPF 1 kHz HPF 10 for fre...

Page 110: ...channels of AES EBU digital audio Ancillary Data Identifies the presence of ancillary data other than audio and EDH and indicates if a checksum error has occurred Format Errors Warns that a serial sig...

Page 111: ...ields and the field rate sync between them Sweep Linearity 1 Magnified Sweep Accuracy 1 Line 0 2 ms division 1 2 Line 1 0 ms division 1 Magnified Sweep Linearity 1 Timing Cursors Accuracy 0 5 at 25 C...

Page 112: ...racy 2 Electronic Graticule Display Lightning Diamond Y is displayed vertically PB is displayed horizontally on top half of display PR is displayed horizontally on bottom half of display GBR Deflectio...

Page 113: ...Internal with variable illumination Table A 15 Environmental Characteristics Characteristic Performance Requirement Reference Information Operating Temperature 0 to 40 C 32 to 122 F Storage Temperatur...

Page 114: ...Humidity Proper operation at 95 0 5 Relative Humidity Do not operate with visible moisture on the circuit boards Table A 16 Certification Characteristic Standard Safety Designed to meet or exceed UL12...

Page 115: ...e location are enabled by ground closures TTL lows Functions with overbars indicate an active low state Eight of the menu selectable front panel RECALL SETUPs can be called up remotely Pin assignments...

Page 116: ...panel setup from this location or se lects the Preset 1 memory loca tion to store the current front panel settings 18 Preset 2 Ground TTL low Recalls the stored front panel setup from this location o...

Page 117: ...a 9 pin D type connector that is provided as the calibration interface See Figure B 2 The WFM601i is intended to be calibrated with a Personal Computer PC 1 2 3 4 5 6 7 8 9 DATA CONNECTION PIN NUMBER...

Page 118: ...Appendix B Multipin Connectors B 4 WFM601i Serial Component Monitor...

Page 119: ...he housing to the rear panel Remove the filter and wash it in a mild detergent and water solution Place cleaned and dried filter or new filter in the housing and replace housing over the fan Replace a...

Page 120: ...C 1 for panel and recess location CAUTION Needle nosed pliers are not recommended 3 To remove a bulb position the tweezer tips on the thin flat portion of the bulb close to the plastic socket Careful...

Page 121: ...milar compounds because they may damage the plastic Exterior Clean the dust from the outside of the instrument with a soft clean cloth or small brush A brush is especially useful for removing dust fro...

Page 122: ...e bezel to the instrument 4 Grasping the bottom of the bezel pull out and upward to remove the bezel from the instrument There are two hinges at the top of the bezel that hold it in place once the bez...

Page 123: ...Glossary...

Page 124: ......

Page 125: ...onvey color information in such a way that the signals go to zero when there is no color in the picture R Y B Y I and Q are all color difference signals for the NTSC system U and V are color differenc...

Page 126: ...typically used for gamma Gamma PAL Since picture monitors have a nonlinear relationship between the input voltage and brightness the signal must be correspondingly predis torted Gamma correction is a...

Page 127: ...used in color television s additive color reproduction system These are the three color signals generated by the camera and used by the picture monitor to produce a picture R Y One of the color differ...

Page 128: ...dulation in the composite signal Vectorscope A specialized oscilloscope which demodulates the video signal and presents a display of R Y versus B Y in NTSC systems or V versus U in PAL systems The ang...

Page 129: ...Index...

Page 130: ......

Page 131: ...3 4 58 0 354 0962 904 3 104 3 588 04 0 404 4 5 9 3 0 354 8 0 2 8 0 2 2 8540 549 583 8 58 0 404 0 8 5 0 2 062 0962 35 9 4 054 2 8 0 E 0962 4 054 2 8 0 8858 9 8 3 4 0 2 9 8A 858 9 804 8858 9 8 3 4 0 88...

Page 132: ...8 0 2 2 8540 0 404 4 8 44 2 0304 9 8 3 4 58 0 404 304 4 04 9 8 3 4 58 0 404 4 5 9 0 354 0962 904 04 2 4 054 2 1 04 2 4 04 2 58 84 4 5 9 04 0 2 6 556 85 46 9 304 4 02 8 2599 8 A 2599 8 M 40 0 6 9 804 8...

Page 133: ...S 6 1 3598 445 649 35987 6 1 1 62 77 3 4 911 1 6646 8 896 6646 1 7 6 1 3598 445 649 35987 6 1 33 1 796 2 387 66 8 437 251 89 88 6 7 8 2 6 1 498 6 37 462 8 6 3 8 897 6 3 3 1 438 39 8 43 846 3 6 372 77...

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