More Information

H Instrument options and accessories, as well as ordering information, are listed beginning on page 17. H Battery operation is discussed beginning on page 112. H A tutorial covering basic instrument operation starts on page 211. H Detailed menu descriptions begin on page 31. H A complete listing of instrument performance specifications is located in Appendix A.
This section lists the options which can be ordered as well as the standard and optional accessories for the WFM 90 and WFM 91. Ordering information is given at the end of the accessories list.

Options

The options listed below can be ordered with the WFM 90 and WFM 91. Listed with the power adapter options are the Tektronix part numbers to be used when ordering replacements. Option AV Wall Unit Power Adapter, European TUV (119-4540-00) 240 V Wall Unit Power Adapter, UK (119-4541-00) 240 V Wall Unit Power Adapter, Australia (119-4542-00) 100 V Wall Unit Power Adapter, Japan (119-4539-00)

Option A2

Option A3

Option A6

Option Myears Warranty/Remedial Service Option MCalibration/Performance Tests Option 33 Travel-line package including: NiCad Battery Pack Viewing Hood Desk Stand Carrying Case for a WFM 90 or WFM 91 and a TSG 90Series signal generator
Getting Started: Options and Accessories

Accessories

Standard accessories are shipped with every instrument while optional accessories must be ordered. Listed below are the standard and optional accessories for the WFM 90 and WFM 91 along with the Tektronix part number to be used when ordering.
Standard Accessories 1 User Manual (070-8968-XX) 120 V Wall Unit Power Adapter, North American (119-4538-00) Carrying Pouch (016-1330-00)
Optional Accessories Service Manual (070-8969-XX) NiCad Battery Pack (146-0107-00) Instrument Desk Stand (386-6787-00) Viewing Hood (011-0167-00) Carrying Case for the WFM 90 and WFM 91 and a TSG 90Series signal generator (016-1344-00) Backlight Replacement Kit (150-0215-00)

Ordering

Options and accessories for the WFM 90 and WFM 91 can be ordered with the instrument, or purchased through a Tektronix field office or distributor. When ordering, include both the option or part number and the description of the option or accessory.
This section gives instructions for the mechanical and electrical installation of the WFM 90 and WFM 91. Included are directions for the packaging of the instrument for shipment.

Instrument Packaging

Unpacking Save the shipping carton and packing materials in case it becomes necessary to ship the instrument to a Tektronix Service Center for service or repair. Check that the following standard accessories are included: H User Manual H 120 V Wall Unit Power Adapter, North American H Carrying Pouch If the instrument was ordered with the travel case (Option 33), the instrument was packaged in the travel case for shipment. Follow the instructions below for repackaging the instrument for shipment. Packaging for Shipment If you ship an instrument to a Tektronix Service Center, follow these packaging instructions: 1. Attach a tag to the instrument showing: the owner, complete address and phone number of someone at your firm who can be contacted, the instrument serial number, and a description of the required service.

Battery Installation and Removal Replacing Alkaline Batteries. The WFM 90 and WFM 91 battery compartment is located under the back panel of the instrument. The battery compartment is opened by turning the screw head at the top of the panel 1/4 turn. A label on the bottom of the battery compartment illustrates the correct battery polarity. The polarity of the alkaline batteries must be correct for the instrument to operate. Figure 12 shows the correct alkaline battery polarity. NOTE. Replacement of Alkaline Batteries Always replace all of the alkaline batteries at the same time when replacing discharged batteries.
Figure 12: Installed polarity of alkaline batteries
Replacing NiCad Batteries. The optional NiCad battery pack has a connector which fits on the jumper in the battery compartment. Be sure the battery connector tab snaps onto the jumper housing to prevent a loss of battery power. To remove the NiCad battery pack, grasp the batteries close to the wire leads. Use your thumb to press in on the top portion of the battery connector tab, and then pull gently upwards. Figure 13 shows how to remove the NiCad battery pack.

Grasp wire

Figure 13: Removing the NiCad battery pack
Operational Jumpers The only operational modifications made to this monitor are done through the menu system. There are no internal jumper settings for modifying the operational configuration of the instrument.

Mechanical Installation

The WFM 90 and WFM 91 are offered with a viewing hood and desk stand as optional accessories that enhance its on-site use. The installation of these accessories is described below. Viewing Hood The optional viewing hood allows the user to readily view the instrument display in well-lighted situations. The hood is attached to the instrument by first applying the supplied Velcro strips to the sides of the instrument, and then pressing the flaps of the viewing hood onto the strips as shown in Figure 14.
Figure 14: Installing the viewing hood
Desk Stand The optional desk stand provides the user with a stable means to hold the instrument upright on a flat surface. The prongs of the stand are inserted into the holes in the back of the instrument as illustrated in Figure 15.
Figure 15: Installing the desk stand
Operation Basics: Functional Overview
This section describes the WFM 90 and WFM 91 controls and connectors. Descriptions of special operating modes begin on page 26. A tutorial which guides you through a procedure exercising the different functions of the instrument begins on page 211. Menu operation is detailed in Using the Menus, starting on page 31.

Keypad Controls

Variable Gain Mode The Variable Gain mode allows the user to vary signal gain for the Waveform and Vector displays between 45% and 155%. The mode is enabled through a menu selection in the Configuration menu. The variable gain adjustment tracks between the Waveform and Vector display modes, and can be adjusted from the Waveform-inPicture display mode. When the Variable Gain mode is enabled, the message GAIN UNCAL is displayed in the on-screen readout. Time-Out Mode The Time-out mode allows the user to automatically shut down the backlight and/or the instrument after there has been no keypad activity for a menu-selected length of time. The Time-out mode enables the user to reduce battery power usage while the instrument is battery powered, and also to extend the life of the backlight bulb. The Time-out mode is enabled through a menu selection in the Configuration menu. When the backlight has been timed out, the LCD display goes blank and the instrument appears to be off. The backlight is turned back on by pressing any keypad button other than the ON button. The backlight shutdown is functional when the instrument is either battery or DC powered. When the instrument power has been timed out, the ON button must be pressed to turn the instrument back on. The instrument power shutdown is only functional when the instrument is battery powered. Calibration Mode The Calibration mode allows the user to adjust the instrument to factory specifications, if necessary. The Calibration mode is entered by pressing and holding the CONFIG button for a few seconds. The instrument adjustments are performed entirely from the keypad with the use of specified input signals. The instructions for readjusting the instrument to specifications are located in the service manual.
CAUTION. Instrument Adjustment Do not attempt to adjust the instrument without using the instructions listed in the service manual, or your instrument may not meet the published specifications.

On-Screen Readout

The WFM 90 and WFM 91 use on-screen messages to alert the user to certain monitoring conditions. Figure 23 shows the readout messages and their locations.

GAIN UNCAL SYNC

EXT REF

10uS/DIV VX.XX

MISSING 100

LOW BAT

Figure 23: On-screen readout messages Readout Description
The GAIN UNCAL message appears in the Waveform, Vector, and Waveform-in-Picture display modes when the Variable Gain mode has been turned on.
The EXT REF message appears in the Waveform and Vector display modes when the video signal is locking to an external video reference signal. The sweep rate is only displayed in the Waveform display mode. There is no sweep rate readout when 2 Field sweep is selected. The MISSING SYNC message appears in all video display modes when the signal reference has been lost. The instrument software version number is displayed when the Configuration menu is open with the DISPLAY category selected. The LOW BAT message is displayed when the instrument is battery operated and the remaining battery power has reached a critically low level. The remaining length of time that the instrument can be operated reliably is dependent on the current operating mode.

Use the right two Bezel Buttons to adjust the signal gain to any desired level. Select VAR GAIN OFF and notice that the waveform gain is restored to 100%. Select VAR GAIN ON again and notice that the waveform gain returns to your adjusted setting. Leave the variable gain on and the Configuration menu open, and proceed to the next step. 4. Using the vectorscope Press the VECT button to enter the Vector display mode. Notice that the Configuration menu is still open and that the vector waveform gain is the same as it was adjusted in the previous step in the Waveform display mode. Turn off the variable gain and press the CONFIG button to exit the Configuration menu. Phase Adjustment. The Arrow Buttons adjust the vector phase. Press and hold the Y button. Notice how fast the phase of the waveform changes. Press and hold the " button. Notice that the phase changes at a much faster rate. The same is true for the B and A buttons. Adjust the burst vector back to the 180 graticule line so that the vector dots land in the target boxes. Bar Amplitude. Select 100% color bars output from the television signal generator. Notice that vector waveform is too large to land in the target boxes. Enter the Configuration menu and select the VECTOR category. Select 100% BARS and notice that the vector waveform now lands in the target boxes. Select 75% color bars output from the signal generator and return the menu setting to 75% BARS. Setup. This menu selection appears in the WFM 90 only. Select SETUP NO from the menu and notice that the vector waveform does not land in the target boxes. Select an NTSC color bar signal without setup from the signal generator and notice that the vector dots again land in the target boxes. Select SETUP YES from the menu and set the signal generator for a 75% color bar output with setup.
Alternate Phase. This menu selection appears in the WFM 91 only. Select ALT PH ON from the menu and notice that the vector waveform now has a mirrored image. Adjust the vector phase with the Arrow Buttons and notice that the mirrored vectors can be overlaid. Select ALT PH OFF from the menu and return the burst vector back to the 180 graticule line.
5. Using the picture monitor Press the PIX button to enter the Picture display mode. Select PICTURE from the Configuration menu category list. Hue. This menu selection appears in the WFM 90 only. Select PICTURE HUE and notice that the right two Bezel Buttons are ready to adjust the picture hue. Press the WFM button to enter the Waveform display mode and notice that the bar over the right two Bezel Buttons now reads ENTER PIX TO ADJ. This message reminds you that the picture hue can only be adjusted while in the Picture display mode. The same is true for the picture color adjustment. Return to the Picture display mode and press the right two Bezel Buttons to adjust the picture hue to a desired setting. NOTE. Resetting the Picture Hue and Color Once the picture hue and/or color has been adjusted, resetting the instrument to the factory default settings, through the Configuration menu PRESETS category, is the only way to ensure that the hue and color have been correctly reset.

H When menu selections are made, changes to the display occur immediately. H When the Configuration menu is open, the Y and B buttons are reassigned from their default function to selecting the menu category. The A and " buttons retain their default function for the currently selected display mode.

Operating Menus

The following pages describe the Operating menus for the different display modes. The Operating menu selections only affect the display mode in which they appear unless otherwise noted. Waveform Display Mode Operating Menu GAIN. Toggles the Waveform display mode vertical gain and the Vector display mode gain between X1 and X5. FILTER. Toggles the Waveform display between FLAT (no filter), and LUM (low-pass filtered for luminance display). SWEEP. Cycles the sweep rate through 1H (5 ms/division), 2H (10 ms/division), and 2F (two field). MAG. Toggles the Waveform horizontal gain between ON and OFF. When MAG is ON, additional sweep rates are available: 1H + MAG (0.5 ms/division), 2H + MAG (1 ms/division), and 2F + MAG (magnified by approximately X20).
Vector Display Mode Operating Menu GAIN. Toggles the Vector display mode gain and the Waveform display mode vertical gain between X1 and X5.
Audio Display Mode Operating Menu REFERENCE dBu. Cycles the Audio reference level through MIC, 10, 0, 4, and 8. The reference levels are measured in dBu, while the MIC level is for testing microphones. HEADROOM. Toggles the headroom reference level between 3 dB and +10 dB. The +10 dB setting is used for viewing signal levels greater than 3 dB over the reference level.
Picture Display Mode Operating Menu ACTION. Toggles the Safe Action area markers ON and OFF. This menu selection appears on the WFM 90 only. TITLE. Toggles the Safe Title area markers ON and OFF. This menu selection appears on the WFM 90 only. SAFE AREA. Toggles the Safe Area markers ON and OFF. This menu selection appears on the WFM 91 only. V SHIFT. Toggles the vertical shift ON and OFF. The vertical shift allows the viewing of the vertical interval on the Picture display. The vertical interval display does not appear on the VIDEO OUT signal.
WIP Display Mode Operating Menu WFM. Selects the Waveform display mode to be shown in the WIP window. VECT. Selects the Vector display mode to be shown in the WIP window.
AUDIO. Selects the Audio display mode to be shown in the WIP window. LOCATION. Cycles the position of the WIP window around the four corners of the Picture display.

Configuration Menu

The Configuration menu is opened by pressing the CONFIG button. A list of menu categories is displayed above the left Bezel Button, while menu selections within the selected category appear over the right three Bezel Buttons. The following pages describe the Configuration menu selections, which are the same for each display mode. The description is organized in the order that the menu categories appear on the display.

Configuration Menu DISPLAY Category VIEW. When VIEW is selected, the right two Bezel Buttons adjust the viewing angle of the LCD display up or down. This adjustment allows for optimal viewing of the display from different positions. BRIGHT. When BRIGHT is selected, the right two Bezel Buttons adjust the brightness of the LCD display.
Configuration Menu INTENS Category TRACE. When TRACE is selected, the right two Bezel Buttons adjust the intensity of the signal trace. GRAT. When GRAT is selected, the right two Bezel Buttons adjust the intensity of the measurement graticule.
Configuration Menu INPUT Category DC REST. Toggles the DC restorer speed between SLOW and FAST. REF. Toggles the video signal reference between INT (internal) and EXT (external reference input signal). When external reference is selected, EXT REF appears in the on-screen readout of the Waveform and Vector displays. When the WFM 90 or WFM 91 loses its signal reference, MISSING SYNC is displayed in the on-screen readout.
Configuration Menu VAR GAIN Category VAR GAIN. Toggles the Variable Gain mode ON and OFF. When ON is selected, the right two Bezel Buttons are assigned to adjusting the signal gain. The Waveform or Vector display modes must be selected in order to adjust variable gain. The first press of one of the right two Bezel Buttons removes the Configuration category list over the left Bezel Button to provide maximum signal viewing, and enables the right two Bezel Buttons to adjust signal gain. Pressing the left Bezel Button redisplays the Configuration category list. When the Variable Gain mode is turned on, GAIN UNCAL is displayed in the on-screen readout of the Waveform, Vector, and Waveform-in-Picture display modes.
Configuration Menu VECTOR Category BARS. Pressing this Bezel Button toggles the calibration of the vector chrominance gain to correctly process 75% and 100% amplitude color bar signals. SETUP. This menu selection appears on the WFM 90 only. Pressing this Bezel Button toggles the vector gain between correctly processing NTSC signals with or without setup.
ALT PH. This menu selection appears on the WFM 91 only. Pressing this Bezel Button toggles the PAL +V mode ON and OFF. When the mode is ON, the phase reference of the V lines is inverted, and then shown as an overlay on the +V lines to provide a comparison display.
Configuration Menu PICTURE Category HUE. This menu selection appears on the WFM 90 only. When HUE is selected, the right two Bezel Buttons adjust the hue of the Picture display. The Picture display mode must be selected before you can adjust the picture hue. COLOR. When COLOR is selected, the right two Bezel Buttons adjust the color of the Picture display. The Picture display mode must be selected before you can adjust the picture color. NOTE. Resetting the Picture Hue and Color Once the picture hue and/or color has been adjusted, resetting the instrument to the factory default settings, through the Configuration PRESETS category, is the only way to ensure that the hue and color have been correctly reset.

Configuration Menu TIME-OUT Category The Time-out mode shuts down power to the Backlight and/or the instrument after there has been no front-panel activity for a menu-selected length of time. BACK LT. Pressing this Bezel Button cycles the Backlight Time-out mode through DISABLED, 2 MIN, and 5 MIN. SHUTDOWN. Pressing this Bezel Button cycles the instrument Time-out mode through DISABLED, 5 MIN, and 10 MIN.
Configuration Menu ALARMS Category ALARM. Pressing this Bezel Button toggles the Alarm mode ON and OFF for the Waveform and Vector display modes.
Configuration Menu PRESETS Category STORE. Stores the current keypad and menu settings in memory for future recall. RECALL. Resets the keypad and menu settings to match the ones that were last stored in memory. DEFAULT. Resets the front panel and menu settings to their factory-set defaults. Monitoring adjustments such as signal position, vector phase, and picture hue are also reset. The default settings of the keypad and menus are listed below. Display mode Signal reference Filter DC restorer speed Gain Variable gain Sweep Mag Bars Setup (WFM 90 only) Alt Phase (WFM 91 only) Reference dBu Headroom WIP location Alarms Safe Action Safe Title Vertical shift Backlight time-out Instrument time-out Waveform Internal Flat Slow X1 Off 2H (2 Line) Off 75% Yes Off 0 dBu 3 dB Bottom right Off Off Off Off Disabled Disabled

Line Select Menu

The Line Select menu is displayed when the Line Select mode is turned on. The number of the selected line and/or field is displayed in the menu bar over the two right Bezel Buttons. FIELDS. Toggles which video fields are displayed between ALL and 1 OF 2. When 1 OF 2 is selected, the menu selection ALT FIELD appears. ALT FIELD. Toggles the display of the selected line between alternating video fields. This menu selection only appears when 1 OF 2 is selected. Up/Down Arrows. The two right Bezel Buttons adjust which line number is selected for display. The menu bar over these two buttons include the displayed line and/or field number.
This section contains descriptions of the different graticules provided with the WFM 90 and WFM 91 and methods for using them to perform basics signal measurements. This monitor uses a proprietary rasterizer to display the graticules. The internal graticule scales are on the same plane as the CRT phosphor, eliminating parallax errors.

Waveform Graticule

There are two versions of the Waveform display mode graticule, illustrated in Figure 31 and Figure 32: H NTSC composite video graticule (WFM 90 only) H PAL (CCIR) composite video graticule (WFM 91 only)
Horizontal Scale The 0 IRE (0.3 V PAL) graticule line is divided into 12 major divisions. Each division represents a unit of time determined by the SWEEP and MAG settings. Line-sweep rates appear in the on-screen readout, and are as follows:

1H (1 LINE) 2H (2 LINE)

TIME/DIV

5 mS/Div 10 mS/Div

MAG ON

0.5 mS/Div 1 mS/Div

In 2F (two field) sweep with MAG on, the signal is magnified by X20, and the entire vertical interval can be viewed.
Reference: Making Measurements
Vertical Scales The NTSC graticule is scaled in IRE units and extends from 40 to +120 IRE, in 10 IRE increments. Black level setup is denoted by a dashed line at 7.5 IRE. The PAL (CCIR) graticule is scaled in volts and extends from 0 to 1.2 V, in 0.1 V increments.

100% White level

7.5 IRE Setup Baseline

Sync tip

Figure 31: NTSC waveform graticule

1.2 1.0 0.8 0.6 0.4

Baseline
Figure 32: PAL waveform graticule
Making Waveform Measurements
Standard Measurements Standard amplitude and timing measurements of the signal are made by positioning the waveform on the graticule. The magnification controls aid in measuring small portions of the waveform. Peak White With the signal blanking level on the graticule baseline, the amplitude of the 100% white reference of a color bar should be on the 100 IRE (1.0 V PAL) graticule line. The Amplitude Alarm mode highlights any portion of the signal which exceeds the 100 IRE (1.0 V PAL) graticule line. DC Restorer Use the SLOW setting for the DC restorer to measure hum or other low-frequency distortions. The FAST setting removes hum from the display so it will not interfere with other measurements. The back porch portion of the input signal is used as the clamping point. NOTE. DC Restorer use with VCRs When using the shuttle mode on VCRs, set the instrument DC restorer speed to slow to prevent the loss of signal sychronization.

Vector Graticule

The Vector display mode permits measurements of hue in terms of the relative phase of the chrominance signal with respect to the color burst. Relative amplitude of chrominance to burst is expressed in terms of the displacement from center (radial dimension of amplitude). The two versions of the vector graticule are illustrated in Figure 33 and Figure 34: H NTSC composite vector graticule (WFM 90 only) H PAL (CCIR) composite vector graticule (WFM 91 only) WFM 90 & WFM 91 User Manual 311
Red Chrominance gain and phase target boxes

R-Y 90_

Magenta Color reference

Q 3 dB Point B-Y 0_

Yellow Burst 180_ Differential gain and phase measurement box 100% and 75% Burst targets

B G CY

Blue I Green Cyan
Figure 33: NTSC vector graticule
Magenta V Chrominance gain and phase target boxes
+V Chrominance gain and phase target boxes Yellow 180_ Differential gain and phase measurement box

3 dB Point U 0_ Blue

100% and 75% Burst targets Green

Color reference

Figure 34: PAL vector graticule
Chrominance Vector Targets The chrominance vectors terminate in a system of graticule targets consisting of two boxes (a small box inside a large box). A sample target is shown in Figure 35. The dimensions of the large boxes represent $10 centered on the exact chrominance phase, and $20% of chrominance amplitude centered around standard amplitude. The dimensions of the smaller boxes represent $2.5 and $2.5 IRE ($3 and $5% PAL) of chrominance amplitude. For the PAL graticule, each chrominance vector related to the +V burst terminates in targets consisting of two boxes (a small box inside a large box). The vectors associated with the V burst terminate in the targets consisting of smaller boxes only.
Figure 35: Vector targets NTSC values (PAL values in parentheses)
Differential Phase and Gain Measurement Box Differential gain (dG) and differential phase (d) measurements use the graticule markings located at the outer edge of the B-Y or U axis 180 line. See Figure 36.

10o d 2d

Figure 36: Differential gain and phase measurement box
Making Vector Measurements
Chroma Bandwidth The horizontal and vertical axes of the vector graticule contain markings for checking chroma bandwidth. A subcarrier frequency sine wave (whose amplitude places it on the outer compass rose) is used as a reference. When the frequency is changed, the diameter of the circle should reduce in size. At a point equal to 70.7% of full amplitude (3 dB), there are gaps in the horizontal and vertical axes. This calibration aid makes it possible to check the 3 dB points of the demodulator output amplifiers.

Audio Graticule

The audio graticule does not utilize a horizontal scale since the signal free-runs at a two-field sweep rate. The vertical scales are comprised of the audio reference level and the selected headroom setting mirrored around the baseline. The audio graticule is illustrated in Figure 37 with 3 dB headroom selected, and in Figure 38 with +10 dB headroom selected.

Electrical Specifications
A-1. Vertical deflection system

CATEGORY DESCRIPTION

Frequency Response
REF: Specifications apply for full screen
height video input signal, with VARIABLE GAIN off.
REQ: Flat Filter 1 V Full Scale: 50 kHz to 6 MHz
within 2% of response at 50 kHz.
REQ: Flat Filter X5 Gain: 50 kHz to 6 MHz within
5% of response at 50 kHz.
REF: Low Pass Filter: w40 dB attenuation
at 3.58 MHz NTSC, 4.43 MHz PAL.
REF: Response at 15 kHz does not vary
between FLAT and LUM (low pass) filters by more than 1%. Deflection Factor
REQ: 1 V Full Scale: 1 V input displayed within

1% of 140 IRE.

REF: Flat filter selected.
REQ: X5 Gain: Gain accuracy within 5% with 1 V

input signal.

REF: X5 Gain Registration: v1 major divi-
sion of vertical shift from baseline between unmagnified and magnified signal.
REQ: Variable Gain Range: Input signals be-
tween 0.8 V and 2 V can be adjusted to 140 IRE (1.0 V) display. 160 mV to 400 mV for X5 Gain.
REQ: Position Range: 1 V signal can be posi-
tioned so that peak white and sync tip can be placed at blanking level, with the DC RESTORER on, regardless of gain setting.
A-1. Vertical deflection system (Continued)

Transi ent Response

height video input signal, with VARIABLE GAIN off, 1 V Full Scale or X5 Gain selected, and FLAT filter selected.

REF: Pulse-to-Bar Ratio:

X1: 0.99:1 to 1.01:1. X5: 0.98:1 to 1.02:1.
REF: Preshoot: v1%. REF: Overshoot: REF: Ringing:
X1: v2%. X5: v4%. X1: v2%. X5: v4%.
REF: Field Rate Tilt: v1%. REF: Line Rate Tilt: v1%.
REQ: Overscan: v2% variation in baseline of
100 IRE (700 mV) 12.5T (20T) modulated pulse as it is positioned over the middle 80% of the screen. Maximum Absolute Input Level
REF: $5 VDC plus peak AC. REF: Displays in excess of 200 IRE
(1.428 V) may cause frequency response aberrations. DC Input Impedance (Unterminated) Video Input Return Loss Video Out Return Loss (75W) Video Out Differential Gain (50% APL) Video Out Differential Phase (50% APL)

REQ: w15 kW.

REF: With input switch in the HIZ position. REF: w40 dB from 50 kHz to 6 MHz with

75 W termination on.

REF: w30 dB from 50 kHz to 6 MHz. REF: Within 1% with a 140 IRE (1.0 V PAL)

unit display.

REF: Within 1 with a 140 IRE (1.0 V PAL)

A-2. DC restoration

DC Restorer Clamp Time Frequency Response at 60 Hz (50 Hz PAL)

REF: Back Porch.

REQ: Attenuation of 60 Hz (50 Hz PAL) on Input
Signal: Slow Mode: v20%. Fast Mode: w90%.
REF: Blanking Level Shift with 10% to 90%
APL Change: APL changes from 50% to either 10% or 90% will cause blanking level shift of 1 IRE unit (7.14 mV PAL) or less.
REF: Blanking Level Shift Due to Presence

or Absence of Burst: 1 IRE unit (7.14 mV) or less shift from no color burst to presence of color burst.

A-3. Audio mode

Reference Levels
REQ: 10 dBu, 0 dBu, +4 dBu, +8 dBu.
REF: Nominal MIC reference: 50 dBu.
Measurement Accuracy Frequency Response Maximum Input Level Amplitude DC Input Impedance Audio Output Connector Maximum Power Output
REQ: 0.5 dB at 1 kHz. REQ: 0.5 dB from 50 Hz to 20 kHz.
REF: +18 dBu. REF: w15 kW. REF: Mini stereo headphone jack. REF: 250 mW.
A-4. Horizontal deflection system
REQ: Sweep will occur in all Horizontal mode
settings with or without synchronization.
REF: Sweep Length: Two Line and
Two Field sweep length is nominally 12 divisions. 1LINE Sweep Repetition Rate 2LINE Sweep Repetition Rate 2FLD Sweep Repetition Rate 2FLD Sweep Magnification Sweep Magnifier Registration Timing Accuracy
REQ: Equal to line-rate of applied video or exter-

nal sync.

REQ: Equal to half line-rate of applied video or

external sync.

REF: Displays 2 full fields, including the
field-rate sync between them.
REF: Approximately X20. REF: Magnification occurs about the cen-

ter of the screen.

REF: All timing and linearity specifications
exclude the first and last major divisions of the unmagnified display.
REQ: 10 ms/division (2LINE): Within 2%. REQ: 5 ms/division (1LINE): Within 2%. REQ: 1 ms/division (2LINE + MAG): Within 2%. REQ: 0.5 ms/division (1LINE + MAG): Within 3%.

Integral Linearity

REQ: Within 1%.
REF: Measured between the 10 ms and
110 ms points on the 10 ms/division (2LINE) sweep. sweep can be positioned on-screen in all sweep modes.

Horizontal Position

REF: Any portion of a synchronized video

A-5. Vector mode

Chrominance Processing Nominal Subcarrier Frequency (FSC) Chrominance Processing Chrominance Bandwidth Chrominance Processing +V Mode (Applicable to PAL operation only) Display Vector Phase Accuracy Display Vector Gain Stability Display Quadrature Phasing Display Differential Phase

REF: NTSC: 3.579545 MHz.

PAL: 4.43361875 MHz.
REQ: Upper 3 dB Point: FSC +500 kHz,
"100 kHz. Lower 3 dB Point: FSC 500 kHz, "100 kHz. panel button. When pushed, V axis is inverted at a 1/2 line rate to produce a single vector display.
REF: +V-type display as selected by front-
REF: "1.25. REF: Measured with color bar signal. REF: Typically "2.5%. REF: Typically "0.5. REF: "1. REF: Measured with 140 IRE (1 V) linearity
signal (5 step, 10 step, or Ramp) with 40 IRE (300 mV) of subcarrier. Display Differential Gain
REF: "1%. REF: Measured with 140 IRE (1 V) linearity
signal (5 step, 10 step, or Ramp) with 40 IRE (300 mV) of subcarrier. Subcarrier Regenerator PullIn Range
REQ: NTSC: "50 Hz of FSC.

PAL: "10 Hz of FSC.

REF: Subcarrier Regenerator free-runs in
absence of appropriate signal. Reference can be burst of either displayed signal or external reference signal. Subcarrier Regenerator PullIn Time
REF: Pull-In Time: Within 1 second, with
subcarrier frequency within 50 Hz (10 Hz for PAL) of FSC.
A-5. Vector mode (Continued)
Subcarrier Regenerator Phase Shift with Subcarrier Frequency Change
REQ: NTSC: "2 from FSC to (FSC + 50 Hz), or
FSC to (FSC 50 Hz). PAL: "2 from FSC to (FSC + 10 Hz), or FSC to (FSC 10 Hz).
Subcarrier Regenerator REQ: "2 from nominal burst amplitude to Phase Shift with Burst Ampli"6 dB. tude Change REF: Internal or External burst reference. Subcarrier Regenerator Phase Shift with Variable Gain Control Subcarrier Regenerator Phase Control Range Subcarrier Regenerator Burst Jitter
REQ: "1 as gain is varied from +3 dB to 6 dB.
REF: 360 continuous rotation.
REF: 0.5 RMS or less. REF: With 140 IRE (1 V) composite video
input. INT or EXT referenced.

A-6. Synchronization

Input Requirements
REQ: Internal Reference: Composite video or
black burst with sync amplitudes 40 IRE (300 mV PAL) "6 dB.
REQ: External Reference: Sync amplitude be-
tween 143 mV and 4 V will synchronize sweeps. External Reference Input
REQ: DC Input Impedance (Unterminated):

VECT button, 2-1 Vector display mode, 1-4 Vector graticule, 3-11 chrominance targets, 3-13 differential phase and gain, 3-14 Vector operating menu, 3-2 VIDEO IN connector, 2-4 VIDEO OUT connector, 2-4 Viewing hood, 1-15
Timeout mode, 2-7 Travel case, 1-10 packing, 1-11 Tutorial, 2-11 required equipment, 2-11
Waveform display mode, 1-3 Waveform graticule, 3-9 Waveform operating menu, 3-2 WaveforminPicture display mode, 1-4 WFM button, 2-1 WIP button, 2-1 WIP display mode, 1-4 WIP operating menu, 3-3

User service, B-1

Variable gain, 2-7

Index4

Tektronix MBD: Products > Handheld Waveform Monitors WFM90 * WFM91 : Charact. Page 1 of 2
Handheld Waveform Monitors

WFM90 * WFM91

CHARACTERISTICS

Operating Modes

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Certifications

http://www.tek.com/Measurement/Products/catalog/wfm90/specs.html?view=print&page=. 8/23/2004
Tektronix MBD: Products > Handheld Waveform Monitors WFM90 * WFM91 : Charact. Page 2 of 2

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Physical Characteristics

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