Tektronix DM44 Instruction Manual Download

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Page 1: ...n 97077 070 2756 00 COMMITTED TO EXCELLENCE PLEASE CHECK FOR CHANGE INFORMATION AT THE REAR OF THIS MANUAL 4658 OSCILLOSCOPE AND DM44 DIGITAL MULTIMETER OPERATORS INSTRUCTION MANUAL Serial Number _ _ __ First Printing MAR 1979 Revised SEP 1981 ...

Page 2: ...on of Tektronix Inc Products of Tektronix Inc and its subsidiaries are covered by U S and foreign patents and or pending patents TEKTRONIX TEK SCOPE MOBILE and 8 are registered trademarks of Tektronix Inc TELEQUI PMENT is a registered trademark of Tektronix U K Limited Printed in U S A Specification and price change privileges are reserved ...

Page 3: ... PANEL 16 LEFT SIDE PANEL 18 RIGHT SIDE PANEL 18 Page BASIC OSCILLOSCOPE DISPLAYS 19 PRELIMINARY 19 PRESET INSTRUMENT CONTROLS 20 NORMAL SWEEP DISPLAY 21 MAGNIFIED SWEEP DISPLAY 22 DELAYED SWEEP DISPLAY 22 ALTERNATE SWEEP DISPLAY 23 X Y DISPLAY 24 SINGLE SWEEP DISPLAY 25 DM44 DISPLAYS AND MEASUREMENTS 26 RESISTANCE 26 VOLTS 28 TEMPERATURE 30 TEMPERATURE ACCURACY CHECKS 32 ADJUSTMENTS AND MEASUREME...

Page 4: ...BETWEEN TWO TIME RELATED PULSES 50 TIME COMPARISON 51 PHASE DIFFERENCE 52 HIGH RESOLUTION PHASE DIFFERENCE 54 PULSE JITTER 55 DELAYED SWEEP MAGNIFICATION 55 Magnified Sweep Starts After Delay 56 Triggered Delay Sweep Magnification 57 BASIC 465B DELAYED SWEEP TIME MEASUREMENTS 58 Time Duration Basic 465B 58 Frequency Basic 465B 60 Rise Time Basic 465B 60 Time Difference Between Repetitive Pulses Ba...

Page 5: ... GENERAL INFORMATION 98 SPECIFICATION 99 OPTION 05 ACCESSORIES 100 OPERATING INFORMATION 100 Installation of Video Graticule 100 Operation of the Sync Separator 101 Triggering the Sweep 102 Vertical Operating Modes Special Considerations 102 Typical Operation 103 Selecting an Individual Line 104 Special Measurements 105 IDENTIFYING FIELDS FRAMES AND LINES IN 525 60 AND 625 50 TV SYSTEMS 105 NTSC C...

Page 6: ...M44 timing check 39 14 Peak to peak waveform voltage 41 15 Instantaneous voltage measurement 43 16 Algebraic addition 44 17 Common mode rejection 45 18 Time duration 47 19 Rise time 49 20 Time difference between two time related pulses 50 21 Phase difference 53 22 High resolution phase difference 54 23 Pulse jitter 55 24 Delayed sweep magnification 57 25 Time duration 59 26 Rise time 60 27 Time di...

Page 7: ...or practices that could result in damage to either the instrument or other property WARNING statements identify conditions or practices that could result in either personal injury or loss of life As Marked on Equipment CAUTION indicates either a personal injury hazard not immediately accessible as you read the marking or a hazard to property including the instrument itself DANGER indicates a perso...

Page 8: ...e ground connection by way of the grounding conductor in the power cord is essential for safe operation Grounding the Product This product is grounded through the grounding conductor of the power cord To avoid electrical shock plug the power cord into a properly wired receptacle before connecting to the product input or output terminals A protective ground connection by way of the grounding conduc...

Page 9: ... your product Replacement fuses should be identical in type voltage rating and current rating Do Not Operate in Explosive Atmospheres To avoid explosion do not operate this product in an atmosphere of explosive gases unless it has been specifically certified for such operation Do Not Remove Covers or Panels To avoid personal injury do not remove covers or panels from this product Do not operate th...

Page 10: ...2756 33 4658 Oscilloscope with DM44 Digital Multimeter viii 465B DM44 Operators REV A AUG 1979 ...

Page 11: ...tive time measurements A X10 magnifier extends the calibrated sweep rate to 2 nano seconds division The instrument operates over a wide variation of line voltages and frequencies with maximum power consumption of approximately 100 watts Increased measurement capabilities are achieved by the 4658 when it is equipped with an optional Tektronix DM44 Digital Multimeter The DM44 measures 0 to 20 megohm...

Page 12: ...ange Selector Bar set for the wrong applied line voltage or if the wrong line fuse is used LINE VOLTAGE SELECTION This instrument operates from either a 115 volt or a 230 volt nominal line voltage source at 48 hertz to 440 hertz To convert the instrument for operation from one line voltage range to the other move the Line Voltage Selector switch located on the right side panel Figure 1 to the posi...

Page 13: ...voltage and plug the selector bar into the desired position 4 Insert the proper fuse selected from Table 2 into its holder Push the cover on and tighten the captive screws Table 1 Regulating Ranges Regulating Regulating Range Range Selector 115 Volt 230 Volt Bar Position Nominal Nominal Upper Holes 108 to 132 volts 216 to 250 volts Middle Holes 104 to 126 volts 208 to 250 volts Lower Holes 99 to 1...

Page 14: ...S DIV control is out of the calibrated detent and the vertical deflection factor is uncalibrated POSITION Controls Determine the vertical position of the display on the crt In the X Y mode the Channel 2 POSITION control moves the display vertically Y axis and the Horizontal POSITION control moves the display horizontally X axis cH 1 OR X and CH 2 OR Y bnc Connectors Provide for application of exte...

Page 15: ...OP orALT mode is selected display of any combination of CH 1 CH 2 ADD and A TRIG VIEW EXT ONLY is allowed When all buttons are out a single trace will be displayed provided that either TRIG MODE is in AUTO or TRIG MODE is in NORM with a triggerable signal applied to a vertical input connector This trace will not display intelligence and is unaffected by position controls NOTE Four display traces m...

Page 16: ...CH 2 ADD or A TRIG VIEW is selected or if the X Y mode is selected CH 2 Displays Channel 2 signals when push button is pressed in 20 MHz BW LIMIT FULL BW OUT Switch Limits the bandwidth of the vertical amplifier to approx imately 20 MHz when pressed in Push button must be depressed and released a second time to regain full 100 MHz bandwidth operation 20 MHz BW LIMIT Indicator This LED is illumi na...

Page 17: ...I I I I I I I I I REV 8 MAR 1981 r RANGe 200mY 2V 20Y ZOOY 1 21tY DDDDDID Figure 3 Display calibrator and DM44 controls connectors and indicators 465B DM44 Operators 2756 036 7 ...

Page 18: ...s not require readjustment during normal use of the instrument TRACE ROTATION Control Screwdriver control used to align trace with the horizontal graticule lines DM44 OPTION Input Connectors Two banana jacks provide COM black and red inputs for de voltage and resist ance measurements Probe Connector Used to connect a temperature probe Readout A 3 digit LED display using five 7 segment arrays Negat...

Page 19: ...nation of the respective 1 ms or 1 JJ s LED If the duration of one event is being measured the LEOs indicate frequency An illuminated 1 ms LED indicates fre quency in kilohertz and an illuminated 1 JJ S LED indicates megahertz Frequency in hertz is indi cated when both LEDs are in a non illuminated state 6 TIME Control Used in conjunction with the DELAY TIME POSITION control in the TIME and 1 TIME...

Page 20: ...he applied trigger signal In the absence of an adequate trigger signal there is no trace When the trigger rate is too low for AUTO use NORM SINGLE SWP When this push button is pressed the A Sweep operates in the single sweep mode After a single sweep is displayed further sweeps cannot be presented until the SINGL SWP push bu tton is again pressed SINGL SWP is useful in displaying and photographing...

Page 21: ...triggering before setting the the A TRIG HOLDOFF control to a position other than NORM COUPUNG Switch Determines method used to couple signals to the trigger generator circuit 465B DM44 Operators AC Signals are capacitively coupled to the input of the trigger circuit De is rejected and signals below about 30 hertz are attenuated Triggering is allowed only on the ac portion of the vertical signal L...

Page 22: ... if it is not time related CH 2 A sample of the signal applied to the CH 2 input is used as a trigger signal Channel 1 signal is unstable if it is not time related LINE A Trigger Circuit Only A sample of the power line sinusoid is used as a trigger signal It is useful when the input signal is time related multiple or submultiple to the line frequency or when it is desirable to provide a stable dis...

Page 23: ...n using the TIME or 1 TIME functions External Trigger Input bnc Connectors Connect ex ternal trigger input signals for A TRIGGER and B DLY D TRIGGER circuits when either EXT or EXT 10 A Trigger only SOURCE is selected HORIZONTAL AND POWER Refer to Figures 5 and 6 for location of items 36 through 47 SA AND B TIME DIV AND DELAY TIME Switches A TIME DIV clear plastic skirt selects the sweep rate of t...

Page 24: ...p rate to 2 nanoseconds division The magnified sweep expands the center division of the unmagnified display 0 5 division either side of the center graticule line VAR Control Provides continuously variable sweep rates between the calibrated settings of the A TIME DIV switch It extends the slowest A Sweep rate to at least 1 25 seconds division The A Sweep rate is calibrated when the control is set f...

Page 25: ...the reference point the Readout indicates a negative time difference NOTE The DM44 may be modified to make the DELAY TIME POSITION control move only the reference point The procedure for making this modification is located in the Maintenance Section of the DM44 Instruction Manual Modification is to be done by qualified service personnel only POWER Switch PULL ON turns instrument power on button pu...

Page 26: ... the DELAY TIME POSITION control TRACE SEP Control Positions the 8 Sweep ver tically when the ALT HORIZ DISPLAY mode is selected B INTENSITY Control Determines the intensity of the 8 Trace REAR PANEL Refer to Figure 7 for location of items 48 through 57 A GATE Output bnc connector provides a positive going pulse coincident with the A Sweep time 8 GATE Output bnc connector provides a positive going...

Page 27: ...I I I I I I I I I REV SEP 1981 CH 1 VAR BAL 57 CH 2 VERT GAIN Figure 7 Rear panel and left side panal controls connectors and indicators 465B DM44 Operators CH2 VAR BAL 2756 07A 17 ...

Page 28: ...he feet on rear panel MOD Slots A number in either slot indicates the instrument contains an option or other modification LEFT SIDE PANEL Variable Balance Controls accessible through left side panei Screwdriver adjustments to set balance of the vertical channels Vertical Gain Controls accessible through left side panell Screwdriver adjustments to set the gain of the vertical channels RIGHT SIDE PA...

Page 29: ...ine Voltage Selector switch and the Regulating Range Selector bar are placed in the proper positions and that the correct fuse is installed for the line voltage being used Refer to the Operating Safety section of this manual for the information and pro cedures relating to line voltage regulating range and fuse selection Verify that the POWER switch is off push button pressed in before plugging the...

Page 30: ...nal to be applied Calibrated detent AC Midrange Not limited push button out Off push button out DISPLAY Fully counterclockwise Midrange Midrange HORIZONTAL TIME DIV Switches A TIME DIV VAR HORIZ DISPLAY X10 MAG POSITION Locked together at 1 ms Calibrated detent A Off push button out Midrange TRIGGER BOTH A AND B IF APPLICABLE SLOPE LEVEL SOURCE COUPLING TRIG MODE A only A TRIG HOLDOFF 0 NORM AC AU...

Page 31: ...ess the BEAM FIND push button and hold it in while adjusting the Channel 1 VOLTS DIV switch to reduce the vertical display size Center the compressed display using the vertical and horizontal POSITION controls release the BEAM FIND push button Adjust LEVEL control if necessary 3 Set the CH 1 VOLTS DIV switch and the vertical and horizontal POSITION controls to locate the display within the graticu...

Page 32: ...ols and obtain a Normal Display NOTE Differential time measurements and measurements using the TIME or 1 TIME functions of the DM44 are invalid when the 8 Trigger SOURCE switch is not set to STARTS AFTER DELAY 2 Set the HORIZ DISPLAY switch to A INTEN and the 8 Trigger SOURCE switch to STARTS AFTER DELAY 3 Pull out on the 8 TIME DIV knob and turn clockwise from counterclockwise stop until the inte...

Page 33: ...e difference between the delayed displays To obtain two delayed displays select the TIME function and set the VERT MODE to ALT CH 1 and CH 2 The DELAY TIME POSITION control is used to position both delayed displays The J TIME control positions only the Channel 2 delayed display ALTERNATE SWEEP DISPLAY 1 Preset instrument controls and obtain a Normal Sweep Display 2 Pull out on the B TIME DIV knob ...

Page 34: ... delayed display X V DISPLAY 1 Preset instrument controls and pull the POWER switch on Allow the instrument to warm up 2 Set the A TIME DIV switch fully counterclockwise to X Y Apply the vertical signal to the CH 2 OR Y input connector and the horizontal signal to the CH 1 OR X input connector 3 Advance the INTENSITY control until the display is visible If the display is not visible with the INTEN...

Page 35: ... SWP push button on the A TRIG MODE switch The next trigger pulse starts the sweep and displays a single trace If no triggers are present the READY indicator should illuminate indicating that the A Sweep generator circuit is set and waiting for a trigger 3 When the sweep is complete the circuit is locked out and the READY indicator turns off 4 Press the SINGL SWP push button again to prepare the c...

Page 36: ...perating in the resistance mode OHMS function selected and a voltage exceeding 120 volts rms is applied between the and COM leads 1 Press the OHMS FUNCTION push button and the 20 Mn RANGE push button see Figure 8 2 Connect the and COM leads to the unknown resistance 3 Observe the readout Press the next lower value RANGE push buttons as necessary to obtain a proper readout see Table 3 NOTE When the...

Page 37: ...I I I I I I I I I RANGE SELECTION Figure 8 Resistance measurement 465B DM44 Operators 465 DM 0 2 2039 9 27 ...

Page 38: ...de peak ac to chassis The DM44 may be damaged if it is operating in the resistance mode OHMS function selected and a volt age exceeding 120 volts rms is applied between the and COM leads If the readout exceeds 1200 volts or the readout blinks indicating overrange immediately disconnect the lead to prevent possible instrument damage 1 Press both the VOLTS FUNCTION push button and the 1 2 kV RANGE p...

Page 39: ...I I I I I I I I I Figure 9 Volts measurement 465B DM44 Operators 465 DM 0 3 2039 1 0 29 ...

Page 40: ...00 2 000 0 200 0 200 0 000 Measurement 1 2 kV 200 V 200 V 20 V 20 V 2 V 2 V 0 2 V 0 2 V 0 V TEMPERATURE The maximum safe voltage on the measurement surface is 100 volts de peak ac above chassis ground The sensor tip is fragile and may break if dropped or subjected to excessive stress Force exerted on the sensor tip should not exceed 20 pounds If the readout exceeds 55 Cor 150 C imme diately remove...

Page 41: ...I I I I I I I I am measurement Temperature Figure 10 I DM44 Operators 4658 E FUNCTION TEMPER eT TOR 31 ...

Page 42: ...e probe damage ensure that only the sealed portion of the probe is immersed see Figure 10 2 Put the probe tip into the water avoiding the sides or bottom of the container Wait for the readout to stabilize indicating the probe has reached the water temperature 3 The readout should be between 2 C to 2 C There should be ice remaining after the test to verify that inserting the probe did not raise the...

Page 43: ...1 1 l l l l l ll l ll llll 1 J J i I J Ii l l l r 1 1 1 jilltl 1 I 40 50 60 70 80 90 100 110 120 50 60 70 80 90 100 I I I I I I I IIII I I I I I I I I I I I I I I I I I I I I I I I I I I I I iijliiiJ flllfil 1111 111 Jiilllllllifl IIIIJiiifj iii iliiiiliJifl jliii ii I iliiJI 130 140 150 160 170 180 190 200 210 100 110 120 130 140 150 l l l l l l ll l ll l lll lll llll l ll lijlilllllllllllilijiii...

Page 44: ...ument OPERATING CONSIDERATIONS GRATICULE The graticule is internally marked on the faceplate of the crt to provide accurate measurements without parallax It is marked with eight vertical and ten horizontal major divisions In addition each major division is divided into five minor divisions The vertical deflection and horizontal timing are calibrated to the graticule so that accurate mea surements ...

Page 45: ...haracteris tic impedance If this is not possible use suitable impedance matching devices PROBE COMPENSATION Misadjustment of probe compensation is one of the greatest sources of operator error Most attenuator probes are equipped with compensation adjustments To ensure optimum measurement accuracy always compensate your probe before making measurements Probe compensation is accomplished as follows ...

Page 46: ...ucing the current levels that can be drawn from the external circuitry during capacitor charging The following procedure should be used whenever the probe tip is connected to a signal source having a different de level than that previously applied especially if the de level difference is more than 10 times the VOLTS DIV setting 1 Set the AC GND DC switch to GND before connect ing the probe tip to ...

Page 47: ...C switch to GND to display a free running trace with no vertical deflection NOTE Normally the resulting trace will be paral al with the center horizontal graticule line and should not require adjustment 3 If the resulting trace is not parallel with the center horizontal graticule line rotate the TRACE ROTA TION adjustment screw located just below the crt graticule see Figure 3 to align the trace w...

Page 48: ... to stablize and center the display NOTE The CALIBRATOR signal is not intended to be used as a precise timing reference It is employed in the following steps only as a convenient means of dem onstrating basic instrument operation 5 Verify a display of approximately one square wave first positive edge to second positive edge per graticule division see Figure 12 Use the horizontal POSITION control t...

Page 49: ...of the reference point NOTE Adjust 8 INTENSITY control if necessary to display reference point 4 Using the DELAY TIME POSITION control move the reference point to a leading edge of the square wave see Figure 13 Point A 5 Using the DM44 TIME control move the time measurement point to the leading edge of the next square wave see Figure 13 Point B t VISIONS 301 30OmV 1 I 1 I I f if H f H 5 J If I I I...

Page 50: ...nd verify rejection of the 1 kHz square wave input Display should show differentiated spikes as a result of filtering circuits 4 Move the A TRIGGER COUPLING lever to HF REJ The display should show rounding off of the rising and falling edges of the square wave input High frequency filtering causes exclusion of components making up the square edges 5 Move the A TRIGGER COUPLING lever to DC and adju...

Page 51: ...VAR VOLTS DIV control is in the calibrated detent vertically position the display so that the negative peak of the waveform coincides with one of the horizontal graticule lines see Figure 14 Point A 3 Horizontally position the display so that one of the positive peaks coincides with the center vertical graticule line see Figure 14 Point B 4 Measure the vertical deflection from peak to peak see Fig...

Page 52: ...visions X 0 5 V divisions 2 3 volts INSTANTANEOUS DC VOLTAGE NOTE Either channel input connector may be used for the signal input Use the VERT MODE switch to select the appropriate channel for display 1 Obtain a Normal Sweep Display refer to Basic Oscilloscope Displays section of this manual Make sure the VAR VOLTS DIV control is in the cal ibrated detent 2 Determine the polarity of the voltage to...

Page 53: ...age vertical distance X divisions polarity or VOLTS DIY X switch setting Also include the attenuation factor of the probe being used if it is not a 1OX scale factor switching probe EXAMPLE The vertical distance measured is 4 6 divisions see Figure 15 The waveform is above the reference line and the VOLTS DIV switch is set to 2 Substituting the given values Instantaneous Voltage 4 6 X 1 X 2 V 9 2 v...

Page 54: ...o not apply signals that exceed the equivalent of about eight times the VOLTS DIV switch settings since large voltages may distort the display For example with a VOLTS DIV switch setting of 0 5 the voltage applied to that channel should not exceed about four volts EXAMPLE Using the graticule center line as zero volts the Channel 1 signal is on a three division positive de level see Figure 16A J lL...

Page 55: ...D mode can also be used to display signals that contain undesirable components These undesirable com ponents can be eliminated through common mode rejection The precautions given under the preceding Algebraic Addition should be observed EXAMPLE The signal applied to the Channel 1 input contains unwanted line frequency components see Figure 17A To remove the undesired components use the follow ing ...

Page 56: ...th the reference signal without disturbing the setting of the VAR VOLTS DIV control The procedure is as follows 1 Set the amplitude of the reference signal to an exact number of vertical divisions by adjusting the VOLTS DIV and VAR VOLTS DIV controls 2 Establish a vertical conversion factor using the following formula reference signal amplitude must be known Vertical reference signal amplitude vol...

Page 57: ...ction factor is then determined by substituting values in the formula Arbitray Deflection 1 5 X 1 volt division 1 5 volts division Factor The amplitude of the unknown signal can then be determined by substituting values in the unknown signal amplitude formula Amplitude 1 5 volts division X 5 divisions 7 5 volts TIME DURATION 1 Obtain a Normal Sweep Display ensure that the VAR TIME DIV control is s...

Page 58: ...duration measurement as follows 1 Measure the time duration of one waveform cycle using the preceding Time Duration measurement procedure 2 Calculate the reciprocal of the time duration value to determine the frequency of the waveform EXAMPLE The signal shown in Figure 18 has a time duration of 16 6 milliseconds Calculating the reciprocal of time duration 1 Frequency t1me duration 16 6 ms RISE TIM...

Page 59: ...icule line and the top of the waveform touches the 100 graticule line 5 Set the TIME DIV switch for a single event display with the rise time spread horizontally as much as possible 6 Horizontally position the display so the 10 point on the waveform intersects the second vertical graticule line see Figure 19 7 Measure the horizontal distance between the 10 and 90 points and calculate the time dura...

Page 60: ...th equal time delays connect the reference signal to Channel 1 and the comparison signal to Channel 2 inputs 4 Depress the CH 1 and CH 2 VERT MODE push buttons Use either CHOP in orALT out VERT MODE switch depending on the frequency of input signals In general CHOP is more suitable for low frequency signals and ALT is best for high frequency signals Center each of the displays vertically see Figur...

Page 61: ...e TIME DIY and the YAR TIME DIY controls Unknown signals can then be quickly and accurately compared with the reference signal without disturbing the setting of the YAR TIME DIY control The procedure is as follows 1 Set the time duration of the reference signal to an exact number of horizontal divisions by adjusting the TIME DIY and YAR TIME DIY controls 2 Establish a horizontal conversion factor ...

Page 62: ...nd one complete cycle spans seven horizontal divisions The arbitrary deflection factor is then determined by substituting values in the formula Arbitrary Deflection 1 37 X 50 JlS division 68 5 JlS division Factor The time duration of the unknown signal can then be computed by substituting values in the formula Time 68 5 jls division X 7 divisions 480 JlS Duratron The frequency of the unknown signa...

Page 63: ...ne cycle of the waveform Position the display and adjust the 8 Measure the horizontal difference between cor responding points on the waveforms at a common horizontal graticule line at 50 of risetime and cal culate the phase difference using the following formula Phase Difference degrees horizontal difference X divisions sweep rate degrees div MEASURE TIME FROM ATO B VAR TIME DIY control to place ...

Page 64: ...es with the magnifier X10 MAG the magnified sweep rate would be 45 10 4 5 division Figure 22 shows the same signals used in Figure 21 but the X10 MAG push button is depressed resulting in a horizontal difference of 6 divisions The phase difference is Phase Difference horizontal difference divisions magnified X sweep rate degrees div Substituting the given values Phase Difference 6 divisions X 4 5 ...

Page 65: ...rtion of the pulse 3 Set the HORIZ DISPLAY switch to B DLY D 4 Referring to Figure 23 measure the distance between Point A and Point 8 in divisions and calculate the pulse jitter time using the following formula Pulse Jitter Time horizontal 8 TIME DIV difference X switch divisions setting I i MEASURE TIME FROM ATOB r I I I T I I j i I i I I j JITTER Figure 23 Pulse jitter I i 1738 34 DELAYED SWEEP...

Page 66: ...ay refer to Basic Oscilloscope Displays section of this manual 2 Set the appropriate VOLTS DIV switch to produce a display about two divisions in amplitude 3 Set the A TIME DIV switch to a sweep rate which displays several waveform cycles 4 Depress the HORIZ DISPLAY ALT push button and set the B DLY D TRIGGER SOURCE switch to STARTS AFTER DELAY If the instrument is equipped with a DM44 verify that...

Page 67: ... A TIME DIV switch setting 8 TIME DIV switch setting EXAMPLE The apparent magnification of a display with an A TIME DIV switch setting of 0 1 ms and a 8 TIME DIV switch setting of 1 p s Substituting the given values Apparent 1 X 10 4 Magnification 1 X 1o 6 100 times Triggered Delay Sweep Magnification The delayed sweep magnification method just described may produce excessive jitter at high appare...

Page 68: ...the 8 Sweep externally 5 Measurements are made and magnification factors are calculated in the same manner described in the Magnified Sweep Starts After Delay procedure BASIC 4658 DELAYED SWEEP TIME MEASUREMENTS Operating the 4658 oscilloscope in ALT HOR IZ DISPLAY or in A INTEN HORIZ DISPLAY will permit time measurements to be made with a greater degree of accuracy than attained with A HORIZ DISP...

Page 69: ...rt of the intensified zone to the second time measurement point see Figure 25 Point B 6 Record the DELAY TIME POSITION control dial setting 7 Determine formula Time Difference or Duration time difference using the following second first l A TIME DIV dial dial switch setting setting setting EXAMPLE The DELAY TIME POSITION dial setting at Point A is 1 20 and the DELAY TIME POSITION dial setting at P...

Page 70: ...and 10 points on the trailing edge of the waveform 1 Obtain a Normal Sweep Display refer to Basic Oscilloscope Displays section of this manual Use a sweep speed setting that displays several cycles or events if possible and ensure that the VAR TIME DIV control is in the calibrated detent 2 Set the VOLTS DIV switch and VAR control or signal amplitude for an exact five division display on either Cha...

Page 71: ...DELAY TIME POSITION dial setting 8 Use the DELAY TIME POSITION control to move the start of the intensified zone until it just touches the intersection of the signal and the 90 graticule line see Figure 26 Point B 9 Record the DELAY TIME POSITION dial setting 10 Determine time difference using the following formula Time Rise second Difference Time di l settmg first J A TIME DIV dial switch setting...

Page 72: ... same vertical reference line Observe the A Sweep display to position the intensified zone to the correct pulse Do not change the settings of the horizontal POSITION controls 6 Record the setting of the DELAY TIME POSITION dial 7 Determine time difference using the following formula Time Difference second dial setting first A TIME DIV dial switch setting setting EXAMPLE The first dial setting is 1...

Page 73: ...equency signals Center each of the displays vertically 5 Depress the HORIZ DISPLAY A INTEN push button and set the B DLY D TRIGGER SOURCE switch to STARTS AFTER DELAY Set the B TIME DIV switch 20 times faster than the A TIME DIV switch when possible to obtain the smallest usable intensified zone Observe intensified zones on the display see Figure 28 Point A and Point B also relate to intensified z...

Page 74: ... reference line as the Channel 1 pulse see Figure 29 Point 8 9 Record the DELAY TIME control dial setting 10 Determine time difference using the following formula second first J A TIME DIV dial dial switch Difference setting setting setting Time EXAMPLE The A TIME DIV switch is set to 50 JS and the 8 TIME DIV switch is set to 2 JS The DELAY TIME POSITION dial setting for the Channel 1 pulse is 2 6...

Page 75: ...ied zones are CH 2 and coincident in time DELAY TIME POSITION control moves both intensified either zones ALTor CHOP either A INTEN Sweep and B Sweep Position of intensified zone on A Sweep is A TRIG determined by DELAY TIME POSITION control VIEW or ADD CH 1 and Two alternating traces for each channel A INTEN Sweep and B Sweep CH 2 and Position of intensified zone on A Sweep is determined by DELAY...

Page 76: ...ied zones on both channels J TIME control moves one intensified zone on each trace One intensified zone on each of two channel traces DELAY TlME POSITION control moves both intensified zones The J TIME control moves only the intensified zone on the Channel 2 trace A INTEN Sweep and B Sweep are displayed Two intensified zones appear on the A trace Two B traces appear at the same vertical position p...

Page 77: ...race and one B Sweep trace for each channel cont A INTEN Sweep and B Sweep are displayed for each channel One intensified CH 1 and zone on each A trace DELAY TIME POSITION control moves both A Sweep CH 2 and intensified zones and both B traces The b TIME control moves only the ALT Channel 2 intensified zone and B trace atn tha B DLY D moda the intensified zones that are displayed in the A INTEN mo...

Page 78: ...move the time measurement point to the right of the reference point 1 Using the DELAY TIME POSITION control move the reference point to a convenient horizontal graticule line see Figure 30 Point A 2 Using the TIME control move the time measurement point along the same horizontal graticule line to the beginning of the next waveform cycle see Figure 30 Point B 68 465B DM44 Operators 0 I T NS FI D I ...

Page 79: ...frequency units 1 ms 1 p s Frequency Units OFF OFF Hz ON OFF kHz OFF ON MHz NOTE A blinking display indicates an overrange condition This will occur under the following conditions With A TIME DIV Switch Set To Decade Multiples Of 1 2 5 Rise Time Using DM44 And Spacing Between Intensified Zones Is Less Than 0 25 division 0 5 division 1 0 division This method is not recommended for extremely fast ri...

Page 80: ...to move the reference point to the 10 graticule line see Figure 31 Point A 5 Adjust the t TIME control to move the time measurement point to the 90 graticule line see Figure 31 Point B 6 Read the rise time on the DM44 Readout INTENSIFIED ZONES l 1 r I j I M SIGNAL AMPLITUDE 1 TI EASURE ME _l l t A I Y 1 HORIZONTAL I DISTANCE j FROM ATO B 465 DM 0 11 2039 29 Figura 31 Rise time Time Difference Betw...

Page 81: ...ure 32 2 Using the DELAY TIME POSITION control move the reference point to the first pulse Figure 32 Point A 3 Observe B Sweep display and center the left wave form leading edge Both intensified zones will move when the DELAY TIME POSITION control is adjusted 4 Using the D TIME control and observing movement of the B Sweep waveform move the time measurement point to the second pulse Figure 32 Poin...

Page 82: ...LAY Three or four positions more clockwise than A TIME DIV Calibrated detent position 1 Using probes or cables having equal time delays con nect the reference signal to Channel 1 and the com parison signal to Channel 2 inputs 2 Adjust VOLTS DIV switches for vertical displays of about two divisions 3 Adjust the channel POSITION controls and the TRACE SEP control for a display similar to Figure 33 C...

Page 83: ... TIME POSITION control to move it to a convenient vertical graticule line 6 Adjust the b TIME control to move the time measurement point to the desired spot on the Channel 2 trace see Figure 33 Point 8 7 Observe the leading edge of the 8 Sweep comparison signal and use the b TIME control to superimpose the reference and comparison signal leading edges 8 Read the time difference on the DM44 Readout...

Page 84: ...ronmental characteristics of the 4658 are presented in Table 8 and physical characteristics listed in Table 9 Table 7 Electrical Characteristics Characteristics Performance Requirements Supplemental Information VERTICAL SYSTEM Deflection Factor Range 5 mV per division to 5 V per division in 10 steps with a 1 2 5 sequence Uncalibrated VAR Range Continuously variable between settings Extends deflect...

Page 85: ...reen with waveform I positioned to upper and lower extremes of graticule area Frequency Response 5 division reference signal centered I vertically from a 25 ohm source with VAR VOLTS DIV control in Bandwidth calibrated detent position I 15 C to 40 C De to at least 100 MHz 40 C to 55 C De to at least 85 MHz I AC Coupled Lower 3 dB Point 1X Probe 10 Hz or less I lOX Probe 1 Hz or less I 4658 DM44 Op...

Page 86: ...ors Supplemental Information 5 division reference signal centered vertically de coupled at all deflection factors from a 25 ohm source with VAR VOLTS DIV control in calibrated detent position 4 4 4 p p or less 5 mV to 2 V 6 6 6 p p or less 5 V setting only Total aberrations less than 6 6 6 p p checked at 5 mV per division Add 2 to all positive going step specifications checked at 5 mV per division...

Page 87: ...Shift as VAR VOLTS DIV 1 0 division or less is Rotated Inverted Trace Shift Less than 2 divisions when switching from non inverted to inverted I Input Gate Current 20 C to 30 C 0 5 nA or less 0 1 divisions at 5 mV I per division 15 C to 55 C 4 nA or less 0 8 divisions at 5 mV per division I Channel Isolation At least 100 1 at 25 MHz Position Range At least 12 and 12 divisions from I graticule cent...

Page 88: ...ont 1 Mil Approximately 20 pF 250 V de peak ac 500 V p p ac at 1 kHz or less 250 V de peak ac 500 V p p ac at 1 kHz or less De to at least 50 MHz At least 1 mV per division 465B DM44 Operators Supplemental Information Within 2 Within 3 Aberrations 2 or less using a P6105 probe CH 1 VERT SIGNAL OUT into CH 2 input AC coupled using 50 ohm 42 inch RG58 A U cable terminated in 50 nat CH 2 input REV A ...

Page 89: ...isions internal or 100 mV Attenuates signals below about 50 kHz external from 50 kHz to 10 MHz I increasing to 1 5 divisions internal or 300 mV external at 100 MHz I HF REJ Coupled Signal 0 5 divisions internal or 50 mV Attenuates signals above about 50 kHz external from 30 Hz to 50 kHz DC Coupled Signal 0 3 divisions internal or 50 mV I external from de to 10 MHz increasing to 1 5 divisions inter...

Page 90: ...ance Requirements TRIGGER SYSTEM cont 250 V de peak ac 250 V p p ac at 1 kHz or less 1 MO At least 2 and 2 V 4 V p p At least 20 and 20 V 40 V p p 100 mV per division 5 1 V per division 5 5 ns or less 4658 DM44 Operators Supplemental Information Within 10 Approximately 20 pF within 10 DC trigger COUPLING only checked with 1 kHz signal 20 MHz BW LIMIT at full bandwidth switch out REV A AUG 1979 I I...

Page 91: ...on HORIZONTAL DEFLECTION SYSTEM 0 5 s per division to 0 02 JJS per division in 23 steps in a 1 2 5 sequence X10 MAG extends maximum sweep rate to 2 ns per division 465B DM44 Operators With a 5 division signal having a 5 ns rise time or less from a 25 ohm source centered vertically with equal 50 ohm cable lengths from signal sources to vertical channel and external trigger inputs terminated in 50 n...

Page 92: ...ision Unmagnified Magnified Accuracy specification applies over the full 10 divisions Within 2 Within 3 When in X10 MAG exclude first and last 50 ns of the sweep on 2 ns 5 ns 10 ns Within 3 Within 4 and 20 ns sweep rates 5 over any two division or less portion of the full 10 divisions When in X10 MAG exclude first and last magnified divisions when checking 2 ns 5 ns and 10 ns per division rates 4 ...

Page 93: ...factor of 10 Within 0 2 divisions from graticule center X10 MAG on to X10 MAG off Start of sweep must position to right of graticule center End of sweep must position to left of graticule center For Measure For Measure With the A TIME DIV switch at ments of One ments of Less 0 5 p s and 0 2 p s the differential time or More than One measurement accuracy limit is valid Major Dial Major Dial only fo...

Page 94: ...ies other than 50 Hz One part or less in 20 000 0 005 of A TIME DIY switch setting when operating on 50 Hz power line frequency Continuous from 0 2 ps to at least With VAR control in calibrated detent 5 seconds after start of the delaying A sweep With TIME DIY switch set to extreme counterclockwise position Same as Vertical System With X10 MAG off De to at least 4 MHz 1O division reference signal ...

Page 95: ... to 55 C Repetition Rate Output Resistance REV A AUG 1979 Table 7 cont Performance Requirements Supplemental Information HORIZONTAL DEFLECTION SYSTEM cont 1 Mn Within 2 Approximately 20 pF Within 3 250 V de peak ac 500 V P P ac at 1 kHz or less 250 V de peak ac 500 V P P ac at 1 kHz or less Within 3 from de to 50 kHz Within 4 CALIBRATOR 0 3 V within 1 5 Approximately 1 kHz Within 25 Approximately ...

Page 96: ...LIBRATOR icontl 30 mA within 2 Z AXIS INPUT 5 volt p p signal causes noticeable modulation at normal intensity De to 50 MHz SIGNAL OUTPUTS At least 50 mV per division into 1 MO At least 25 mV per division into 50 n De to at least 50 MHz into 50 0 465B DM44 Operators Supplemental Information 30 rnA within 2 5 Positive going signal decreases intensity 25 V de peak ac Approximately 50 0 Approximately...

Page 97: ...Line Frequency Power Consumption Typical Maximum Table 7 cont Performance Requirements Supplemental Information POWER SOURCE 99 V to 121 V 104 V to 126 V 108 V to 132 V 198 V to 242 V 208 V to 250 V 216 V to 250 V 48 Hz to 440 Hz 65 W at 115 V 60Hz medium range 85 W at 115 V 60Hz medium range 4658 DM44 Operators 87 ...

Page 98: ...10 em P31 P11 DM44 0 to 1 2 kV in 5 steps 200 mV 2 V 20 V 200 V and 1 2 kV 100J tV Within 0 1 of reading 1 count 10 MO all ranges user has option to remove an internal wire strap to increase input resistance to 1000 MO on the 200 mV and 2 V ranges 465B DM44 Operators Supplemental Information 0 1 division or less of tilt or bowing Adequate to align trace with horizontal center line At least 3 I I I...

Page 99: ...solution Table 7 cent Performance Requirements Supplemental Information DM44 cont At least 60 dB at 50 and 60Hz At least 100 dB at de 80 dB at 50 and 60Hz Approximately 3 3 measurements per second Within 0 5 second 45 parts milliontc 1200 V de peak ac between and COM inputs or between input and chassis 500 V de peak ac to chassis 0 to 20 M Q in six steps 200 n 2 k Q 20 k Q 200 k Q 2 M Q and 2oMn 0...

Page 100: ...200 il 2 kil and 20 Mil Ranges 90 Table 7 cont Performance Requirements DM44_1con_tl_ Within 0 25 1 count probe resistance Within 0 25 1 count Within 0 30 1 count Approximately 3 3 measurements per second Within 1 second Within 5 seconds 120 V rms between and COM inputs for an indefinite time 465B DM44 Operators Supplemental Information 220 V rms between and COM inputs for 1 minute or less 250 par...

Page 101: ... C to 35 C 15 C to 55 C Table 7 cont Performance Requirements Supplemental Information DM44 contl OHMS RANGE CURRENT 200 nand 2 k Q 1 rnA 20 k Q 100J LA 200 k Q 10J LA 2M Q 1 J LA 20M Q 100 nA 55 C to 150 C in one range Ambient Probe Tip Temperature Temperature Accuracy oC oC oC 15to 35 55 to 150 2 15 to 55 55 to 125 3 15 to 55 125to 150 4 15 to 35 55 to 150 6 15 to 55 55 to 150 8 Within 1 of read...

Page 102: ...quirements Supplemental Information DM44 cont Within 2 of reading 1 count Within 3 5 1 count Table 8 Environmental Characteristics Description 15 C to 55 C 62 C to 85 C To 4 500 m 15 000 ft Maximum operating temperature decreased 1 C per 300 m 1 000 ft above 1 500 m 5 000 ft To 15 000 m 50 000 ft 465B DM44 Operators REV A AUG 1979 I I I I I I I I I ...

Page 103: ...2 2 Class C 95 to 97 humidity 15 minutes along each of three major axes at a total displacement of 0 025 inch p p 4 gat 55 Hz with frequency varied from 10Hz to 55 Hz to 10Hz in one minute sweeps After sweep vibration in each axis frequency held steady at each major resonance for 10 minutes or if no such resonances found held at 55 Hz for 10 minutes 30 g half sine 11 ms duration 3 shocks per axis ...

Page 104: ...ithout Pouch Width With Handle Without Handle Depth Including Panel Cover With Handle Extended 94 Table 9 cont 14 9 kg 32 71b Approximately 22 kg 48 lb 19 1 em 7 5 in 15 7 em 6 2 in 32 8cm 12 9 in 29 2 em 11 5 in 46 0cm 18 1 in 51 6 em 20 3 in 465B DM44 Operators Description I I I I I I I I I ...

Page 105: ...016 01 003 0120 00 070 2036 01 01 0 6430 00 C 5B Option 02 low cost general purpose Camera Order C 5B Option 02 Protective Cover Waterproof blue vinyl Order 016 0554 00 Polarized Collapsible Viewing Hood Order 016 0180 00 Folding Viewing Hood light shielding Order 016 0592 00 Collapsible Viewing Hood binocular Order 016 0566 00 Mesh Filter Improves contrast and emi filter Order 378 0726 01 SCOPE M...

Page 106: ...ng instructions presented in this manual OPTION OS Option 05 when installed in the 4658 oscilloscope adds a TV Sync Separator and other changes to provide stable sweep triggering from composite video waveforms Two positions are added to the A TRIGGER COUPLING switch TV FIELD and TV LINE When these positions are selected the A Sweep may be triggered at the Field or Line rate with the A TRIGGER LEVE...

Page 107: ...e 24 volt ex ternal input permits use with marine and aircraft con ventional de power The modified oscilloscope has a three position voltage input selection slide switch visible through the right hand side panel at the rear of the line voltage selector switch A de input connector is located below the fan cover on the rear panel Option 07 is not provided with 4658 oscilloscopes equipped with the DM...

Page 108: ...D or TV LINE coupling When the A TRIGGER COUPLING switch is set to TV FIELD or TV LINE the output of the Sync Separator is automatically applied to the A Sweep Trigger circuits and only this signal may be used for triggering the A Sweep For B Sweep the horizontal sync signal line rate sync from the Separator is fed only to the TV LINE position on the B TRIGGER SOURCE switch which may be selected a...

Page 109: ...ive Probe 1 Mn 2 24 pF 2 24p s 2 3dB 1 Hz 0 1 Hz 2 5 o 25 Triggering Sync Separation Amplitude p p Internal Composite Video nominal 1 Composite sync External Composite video nominal Composite sync Ext 1 0 Composite video nominal Composite sync 1Peak video 7 3 sync amplitude 465B DM44 Operators Stable video rejection and sync separation from sync positive or sync negative composite video 405 to 819...

Page 110: ...king on the outside NOTE The extended tab at the bottom of the graticule mates with the slightly wider bottom margin of the graticule cover The graticule can be moved slightly horizontally to align the external graticule and mask with the crt graticule and viewing area Reinstall the bezel When the video graticule is installed the 10 horizontal divisions along line 0 correspond to the internal grat...

Page 111: ...ave form should be at least 10 units or 0 5 division on the CCIR graticule 14 units or about 0 75 division on the NTSC graticule For external triggering the sync portion of the waveform should be at least 75 mV in amplitude or 0 75 V in the EXT 10 mode Do not exceed the indicated maximum amplitudes 20 divisions for internal triggering 40 volts for external triggering to avoid circuit overloads and...

Page 112: ...or is not capable of correct processing of switched composite vertical deflection wave forms present on the NORM bus in the ALT or CHOP modes it is therefore not possible to obtain stable simultaneous displays of two independent video signals that are not time related SINGLE CHANNEL TRIGGERING When triggering from Channel 1 or Channel 2 the waveform fed to the Sync Separator is the same except for...

Page 113: ...play an odd number of fields plus a fraction of a field in the unmagnified display For 50 and 60 Hz field rates the 2 ms div setting is usually selected For some PAL system observations a setting of 5 ms div approximately 2 field display with the A TRIGGER HOLDOFF control set to approximately the four o clock position additional one field holdoff may be desirable to maintain a stable display relat...

Page 114: ...ufficient resolution to identify the field Adjust the A TRIGGER HOLDOFF as necessary If the displayed field is not the desired one first rotate the A TRIGGER SLOPE control momentarily to the opposite polarity then rotate back again until the start of the desired field is displayed Press A INTEN and use the DELAY TIME POSITION control to position the intensified zone 8 Sweep on the desired line Pre...

Page 115: ...me FM and TV transmitters may show objectionable amounts of rf signal energy in the display even when coaxial input connections are used The front panel 20 MHz BW LIMIT switch will usually eliminate such interference from the display but will not affect the signal reaching the Sync Separator Where the rf interferes with Sync Separator operation external filters will be required Use of probes desig...

Page 116: ...eld PAL sequence with Bruch Sequence Color burst blanking the fields are identified as follows Field 1 Field that follows a field ending in a half line of video when preceding field has color burst on the last full line Field 1 lines are 1 through 312 and half of line 313 Color burst starts on line 7 of Field 1 a half line of video appears on line 23 Field 2 Field that follows a field ending in a ...

Page 117: ...r or power lead is 50 volts with respect to oscilloscope chassis or ground CONTROLS AND CONNECTORS Mode Switch Three position switch located adjacent to the Line Voltage Selector switch on the right side panel and used to select the proper input power to the 4658 AC DC12 DC24 DC Input Connector 465B DM44 Operators Permits application of ac power to the oscilloscope power switch Permits operation o...

Page 118: ...charged Order Tektronix 1106 Battery Pack OPERATING INFORMATION To operate the 465B Option 07 oscilloscope Connect the oscilloscope frame to a ground earth reference before using 1 Set the 465B Line Selector switch and the Option 07 Mode switch to the appropriate positions for the power source to be used Refer to the following table for proper switch positions Power Source 4658 Line Option 07 Sele...

Page 119: ...I I I I I I I I I NOTES ...

Page 120: ...NOTES I I I I I li I I I ...

Page 121: ...and composite video TV signals in comparison with the old Option 05 and provides a FIELD 1 or FIELD 2 sync selection feature lhe new Option 05 requires that the polarity of the input signals be observed since the SYNC SEPARA IDR operates on sync negative signals only Operation of the instrument from sync positive signals is described in operation of the sync separator under Operating Instructions ...

Page 122: ...a TV Sync Separator and provides the instrument with front panel selection of additional trigger signal processing to facilitate observation and measurement of composite video and related television waveforms Added circuitry provides amplification clipping and vertical sync recognition Vertical field rate and horizontal line rate trigger signals are selected with the A TRIGGER COUPLING switch for ...

Page 123: ... front panel showing Option 5 features Page 3 of 23 DELAY TIME POSITION BIDLY Dl TRIGGER CODUPUNGAC n rr u o J ME b 0 UNCAL ms 2 l S z l 50 Z1 01D o1D5 20 2 511 1 1 5 ADNLY J 2 AUDY I i 1 A 0 DISPlAY a Dlf l 0 o 11IG MODE 0 ATRIGGER AUTO COUMIG SOURCf E ULFACRU D HFRU Dll 0 DC LIHI _ _ I EXT Om Ext RESET If NORM IVIOIV E os A IIIICAUSE SERIAl ...

Page 124: ...TV LINE coupling With the A TRIGGER COUPLING switch set to either TV FIElD or TV LINE the selected sync output from the Sync Separator is automatically applied to the A SWeep TRIGGER circuit for use as the triggering signal for the A SWeep For the B SWeep the horizontal sync signal line rate sync from the Sync Separator is fed only to the TV LINE position of the B TRIGGER SOURCE switch to be selec...

Page 125: ...reases the input shunt capacitance to a normalized value of 24 pF Specification Electrical characteristics and performance requirements listed in the Specification part of this manual are applicable to the 465B cption 05 oscilloscope with the following exceptions or additions Vertical Input AC Input Coupling Iesistance 1 Megohm within 2 Low Frequency 3dB Point Capacitance 24 pF 10 Time Constant 24...

Page 126: ...ync negative composite video 405 to 1201 line 50 or 60 Hz field rate Sync positive composite video can be separated by applying the input signal to the CH 2 input connector and using the CH 2 INVERT feature FIELD 1 and FIELD 2 trigger signals are selectable with the A TRIGGER SLOPE switch for interlaced field systems A trigger signal is generated for every field in noninterlaced field systems Page...

Page 127: ... Internal CompositeaVideo nominal 1 5an 15 an I Composite Sync fiJ 5 an 2fiJ an External I Composite Video nominal a 15fiJ mV 1 5V Composite Sync 5fiJ mV 2 fiJ v I EXT lfiJ Composite Video nominal a 1 5V 15 v Composite Sync 5fiJfiJ mV 2fiJ v I a Peak video is approximately 7 3 sync amplitude I Page 7 of 23 t ...

Page 128: ...ith Option 5 instruments 1 Graticule NTSC CCIR System M 4 to 1 units with 7 5 unit setup line horizontal divisions along line zero Tektronix Part Number 337 1674 2 1 Graticule CCIR line horizontal 337 1674 3 CCIR System B divisions along zero to 1 units 35 unit setup line 3 Tektronix Part Number Page 8 of 23 I I I I I I I I I ...

Page 129: ...ve the bezel 2 Remove the implosion shield from the two bosses on the bezel and install the desired graticule ensuring that the markings are on the surface away from the crt face The graticule can be positioned horizontally a small amount to align the external graticule and mask with the internal crt graticule lines NOTE The extended tab at the bottom of the video graticule mates with the slightly...

Page 130: ...changed However the vertical divisions represent only proportions of the 100 unit CCIR or the 140 unit NTSC video waveform and the vertical VOLTS DIV calibration is inapplicable Tb calibrate for a standard 1 volt nominal video signal apply the 300 mV CALIBRATOR square wave signal to either the CH 1 or CH 2 vertical input and adjust the associated VOLTS DIV and VOLTS DIV VAR controls so that the di...

Page 131: ...egative video with sync at the negative peak Tb obtain proper Sync Separator operation from inverted sync positive video sync at the positive peaks and peak video at the negative peaks apply the signal to the CH 2 input connector select CH 2 as the A TRIGGER SOURCE and use the CH 2 INVERT feature to obtain the proper signal polarity NarE Composite Sync is the vertical and horizontal sync signals c...

Page 132: ...ision For external triggering the sync portion of the waveform should be at least 50 mv in amplitude or 0 50 V with the SOURCE switch set to EXT 10 TO avoid circuit overload and partial or complete loss of sync do not exceed the specified maximum composite video amplitude 15 div for internal triggering 1 5 V for external triggering Triggering the Sweep The output of the Sync Separator is fed via t...

Page 133: ...ying Fields Frames and Lines in 525 60 and 625 50 TV Systems to identify the specific field being viewed Tb trigger the B Sweep from the line rate trigger output of the Sync Separator perform the following steps 1 Set the A TRIGGER COOPLING switch to either TV FIELD or TV LINE and ensure that the A Sweep is running NOTE Ihe B Sweep cannot be operated independently of the A Sweep and cannot run mor...

Page 134: ...the NORM trigger signal line in either the ALT or CHOP dual trace vertical mode it is therefore not possible to obtain stable simultaneous displays of two independent video signals that are not time related SINGLE cHANNEL TRIGGERING When triggering from Channel 1 or Channel 2 the waveform fed to the Sync Separator is the same except for positioning as that displayed on the crt when the channel is ...

Page 135: ...plitude is not affected by contribution of the other channel to an ADD vertical mode display When the ADD mode with Channel 2 inverted is used to compare two video waveforms by subtraction the Channel 1 or Channel 2 signal to the Sync Separator will be adequate for stable triggering providing the individual channel signal meets the triggering requirements including correct polarity When the ADD mo...

Page 136: ...vision approximately a 2 1 2 field display with the A TRIGGER HOLDOFF control set to approximately the four o clock position additional one field holdoff may be desirable to maintain a stable display relationship to the four field PAL burst blanking sequence All detailed measurements are then made using the B SWeep HORIZ DISPLAY switches set either to B DLY D or ALT with the B TRIGGER SOURCE switc...

Page 137: ...onsecutive pulses Use the Xl0 MAG switch to display the second pulse at 1 us division sweep rate For rise and fall time measurements on blanking and sync waveforms trigger the A or B SWeep directly from the displayed waveform avoiding the processing delay of the Sync Separator This permits viewing the trigger edge at sweep rates from 0 5 us division to 0 02 us division Selecting an Individual Line...

Page 138: ...one B SWeep on the desired line Pressing the B DLY D button will then display the desired line on the B trace Set OORIZ DISPLAY to ALT to view the A INTEN trace and B DLY D trace simultaneously IWG FAAME CYCLE If PAL burst blanking is to be checked set the A Sweep time for a 3 1 2 field cycle 5 ms division with the A TRIGGER HOLDOFF control set to about the four o clock position Then use the B Swe...

Page 139: ...nse aberrations in the main vertical amplifier will be increased when the signal is driven offscreen and the aberrations will become relatively serious if the amplifier is driven to saturation and cutoff HORIZCNTAL SYNC PUlSE MEASUREMENTS Measurements of the rise and fall times and the width of horizontal sync pulses typically do not require use of the Sync Separator except when only certain lines...

Page 140: ...ed to the Sync Separator Where rf energy interferes with Sync Separator operation external filters will be required Use of probes designed for 10 to 30 MHz bandwidth oscilloscopes will provide 6 to 10 dB attenuation in the 50 to 100 MHz range and may be beneficial in reducing rf interference Identifying Fields Frames and Lines in 525 60 and 625 50 TV Systems NTSC CCIR SYSTEM M Field 1 is defined a...

Page 141: ...ields 1 and 4 positive going zero crossovers of the reference subcarrier nominally coincide with the leading edge of even numbered horizontal sync pulses In Fields 2 and 3 negative going zero crossovers of the reference subcarrier nominally coincide with the leading edge of even numbered horizontal sync pulses CCIR SYSTEM B AND SIMILAR 625 50 SYSTEMS Except for PAL systems identification of parts ...

Page 142: ...6 full line of video The first field is referred to as odd and the second field is referred to as even Note that while the identification systems for System Mand System B are reversed the correct field sync Field 1 or Field 2 is selected indicated by the A TRIGGER SLOPE switch setting In the four field PAL sequence with Bruch Sequence Color Burst blanking the fields are identified as follows Field...

Page 143: ...o color burst on the last full line Field 3 lines are 1 through the first half of line 313 Burst starts on line 6 llnmediately following the last equalizing pulse one half line of video appears on line 23 Field 4 Field that follows a field ending in a full line of video carrying color burst Field 4 lines are the second half of line 313 through line 625 Color burst for Field 4 starts on line 320 tw...

Page 144: ...I I I I I I I I I ...

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