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Summary of Contents for 7B71

Page 1: ...Tektronix Inc P O Box 500 Beaverton Oregon 97005 TEKTRONIX DELAYING TIME BASE SN B2050D0 AND UP INSTRUCTION MANUAL Serial Number JtXiiD 070 1580 00 373...

Page 2: ...re you the fastest possible service Please include the instrument Type Number or Part Number and Serial Number with all requests for parte or service j s Specifications and price change privileges res...

Page 3: ...sitivity 1 2 Environmental Characteristics Altitude 1 2 Physical Characteristics Finish 1 2 Dimensions 1 2 Weight 1 2 SECTION 2 OPERATING INSTRUCTIONS General 2 1 Installation 2 1 Front Panel Controls...

Page 4: ...t Description 3 1 Trigger Input 3 1 Input Source 3 1 Trigger Amplifier 3 2 General 3 2 External Input Amplifier 3 2 Input Stage 3 2 Peak Detector 3 3 Slope Comparator 3 3 Output Stage 3 4 Trigger Gene...

Page 5: ...orm Procedure and Index 5 2 Performance Check Calibration Procedure 5 4 General 5 4 Preliminary Control Settings 5 5 Check Adjust Steps refer to Short Form Procedure 5 5 for index to steps SECTION 6 E...

Page 6: ...PE SiNGlE FINE POSITION R T MAGNIFIER READY VARJABiE CAL IN time div ORDLYTIME B DELAY MODE A INTER DURING 8 II INDEPENDENT B STARTS AFTER DELAY 8 TRIGGERABLE AFTER DELAY DELAY TIME MULT DELAYING TIME...

Page 7: ...e of 0 C to 50 C unless otherwise noted Warmup time for given accuracy is 20 minutes TABLE 1 1 Electrical Characteristics Characteristic Performance Sweep Rate Calibrated Range 5 seconds division to 0...

Page 8: ...ng Only the specified upper 3 dB frequency of the Vertical System replaces upper limit frequencies in the above table when the number in the table is greater than the 3 dB frequency of the Vertical Sy...

Page 9: ...plug in compartment push it in until it fits firmly into the indicator plug in compart ment To remove pull the release latch see Fig 2 1 to disengage the unit from the indicator and pull it out of th...

Page 10: ...ies of push button switches to select the trigger mode Selected mode is indicated by lighted button P P AUTO Sweep automatically triggered at point selected by the LEVEL SLOPE control when the trigger...

Page 11: ...es of push button switches to select the trigger coupling Selected coupling is indicated by lighted button AC Rejects DC and attenuates AC signals below about 30 hertz Accepts signals between 30 hertz...

Page 12: ...operate independently as normal time base units B STARTS AFTER DELAY The companion delayed sweep unit B produces a sweep immediate ly following the delay time selected by the TIME DIV OR DLY TIME swit...

Page 13: ...Operating lnstructions 7B71 SN B205000 and Up 7B71 TEST SET UP CHART NOTES Fig 2 3 7B71 Test Setup Chart...

Page 14: ...h and POSITION control for a display which remains on the display area horizontally VARIABLE control should be in CAL position for cali brated sweep rates 5 If the display does not start at the correc...

Page 15: ...his range on either slope In the P P AUTO mode the trigger circuit automatically compensates for changes in trigger signal amplitude for signals above the minimum amplitude requirement Therefore if th...

Page 16: ...he SINGLE SWP MODE is also useful to photograph non repetitive or unstable displays To obtain a single sweep display of a repetitive signal first obtain the best possible display in the NORM MODE Then...

Page 17: ...el one of the remaining COUPLING switch positions will provide a better display The triggering point in the AC position depends upon the average voltage level of the trigger signal If the trigger sign...

Page 18: ...e EXT 10 position is the same as described for EXT except that the external signal is attenuated 10 times Attenuation of high amplitude exter nal trigger signals is desirable to broaden the range of t...

Page 19: ...Operating lnstructions 7B71 SN B205000 and Up CRT displays obtained with LEVEL SLOPE control in negative slope region Fig 2 7 Effect of LEVEL SLOPE control on CRT display AUTO P P MODE 2 n...

Page 20: ...2 nanoseconds division with MAGNIFIER at X10 to about 12 5 seconds division When making time measurements from the graticule the area between the second division and tenth division vertical lines of t...

Page 21: ...rk 1965 Robert G Middleton and L Donald Payne Using the Oscilloscope in Industrial Electronics Howard W Sams Co Inc The Bobbs Merrill Company Inc Indianapolis 1961 1 Connect the reference signal to th...

Page 22: ...repetition rate of an unknown signal which completes one cycle in seven horizontal divisions can be determined by using the repetition rate formula step 6 Example Assume that the distance between the...

Page 23: ...t number of divisions in amplitude 4 Center the display about the center horizontal line with the vertical POSITION control 5 Set the A Triggering controls to obtain a stable display 6 Set the TIME DI...

Page 24: ...MODE selector to CHOP or ALT see Oscilloscope Manual discussion on hori zontal mode switching to display both Time Base sweeps 2 Set the VOLTS DIV selector to produce a display about three divisions...

Page 25: ...uses the B STARTS AFTER DELAY posi tion to allow the delayed portion to be positioned with the DELAY TIME MULTIPLIER dial If there is too much jitter in the delayed display use the Triggered Delayed S...

Page 26: ...ny greater detail because the sweep is triggered by the larger amplitude pulses at the start of the display and a faster sweep rate moves this area of the wave imnnnini nTnni TiiiTrrnmniiTmTmimw mnimn...

Page 27: ...nal produced by sweep gener ator circuits The sweep gate multivibrator produces a Sweep Gate for use by the indicator oscilloscope The bright line auto feature which provides a free running trace in t...

Page 28: ...or network in the input to this ampli fier can be selected by the front panel EXT i 10 push button to extend the triggering level range of the unit TRIGGER AMPLIFIER General The Trigger Amplifier circ...

Page 29: ...nput stage and applied through CR210 to the peak sensing network C210 charges to the peak value of the input signal The signal is amplified by Q220 Q224 and applied to the gate of source follower Q248...

Page 30: ...ulse from the Trigger Pulse Gener ator enables CR319 opening an additional current path for VR358 the sweep gate tunnel diode VR358 switches to its high voltage state applying a positive signal to the...

Page 31: ...55 and discon nects the bright line auto circuit from the sweep gate stage but allows the TRIG D light to function TIME BASE GENERATOR General The Time Base Generator circuit see Fig 3 4 produces a sa...

Page 32: ...ART GATE SAWTOOTH DISCONNECT SWEEP AMPLIFIER 1 GENERATOR 0526 L 0532 0533 S ny 0534 0537 SAWTOOTH TO HORIZONTAL PREAMP SWEEP START AMPLIFIER 0592 SWEEP STOP COMPARATOR 0406 0408 RESET TO SWEEP GATE ST...

Page 33: ...nt of Q582 VR576 and CR576 limit the negative voltage on the hold off capacitor C580 The HF STAB control R 146B through R583 varies the discharge rate of the holdoff capacitor to provide a stable disp...

Page 34: ...gain turned off Alternate Operation In alternate operation the indicator oscilloscope pro vides a sweep inhibit current to the emitter of 0410 0410 provides a low impedance input and a voltage drive f...

Page 35: ...negative going step at the collector of Q492 is applied to the base of Delay Gate Emitter Follower Q496 The negative going step at the emitter of Q496 is sent to the Indicator Oscilloscope as the Dela...

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Page 37: ...for dislodging dirt on and around the front panel controls Dirt which remains can be removed with a soft cloth dampened in a mild detergent and water solution Abrasive cleaners should not be used Int...

Page 38: ...are color coded in picofarads using a modified EIA code see Fig 4 1 Diode Color Code The cathode end of each glass encased diode is indicated by a stripe a series of stripes or a dot For most silicon...

Page 39: ...not be obtained in the EXT mode the external trigger amplifier or the SOURCE switch is prob ably at fault When trouble symptoms appear use the front panel controls and the CRT display to try to isolat...

Page 40: ...Maintenance 7B71 SISl B205000 and Up Fig 4 2 Troubleshooting chart for the 7B71 lAl 4 4...

Page 41: ...aintenance 7 B71 SIM B205000 and Up For a trouble not covered by this chart use the troubleshooting methods in steps 6 and 7 of the troubleshooting techniques Fig 4 2 Troubleshooting chart for the 7B7...

Page 42: ...scale The diode resistance should be very high in one direction and very low when the meter leads are reversed Do not check tunnel diodes or back diodes with an ohmmeter CAUTION Do not use an ohmmete...

Page 43: ...flux with a flux removing solvent Be careful that the solvent does not re move any printing from the circuit board Metal Terminals When soldering metal terminals e g switch terminals potentiometers et...

Page 44: ...ircuit board Use the minimum amount of heat necessary to remove the pin The new pins are supplied with ferrules intact Remove the ferrule from the new pin before inserting the pin into the old ferrule...

Page 45: ...osen the set screw on the collar securing the VARIABLE shaft to the VARIABLE potentiometer and pull the shaft completely out the front of the unit Loosen the two set screws on the TIME DIV knob and re...

Page 46: ...on of the old bulb Reassemble by reversing the above procedure Instrument Repackaging If the 7B71 is to be shipped for long distances by com mercial means of transportation it is recommended that the...

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Page 48: ...R Magnifier f...

Page 49: ...RAP CR702 CR204 cr7o5 I KSj CRfl2 cR fa CR722 JtRAP STRAP Ja s ilW R721 R7QqW M R705 strap STRAP C STRAP I f fl R461 I 5 R728j f R724 i r713 1s ir R723p R71 1 r iR704 R702f R7011 I CR703 C STRAP i Si...

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Page 51: ...C1 Maintenance 7B71 SN B205000 and Up Fig 4 8 External board showing location of components...

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Page 53: ...formance data or to check off steps as they are completed This procedure may be reproduced and used as a permanent record of instrument calibration NOTE AH waveforms shown in this procedure were taken...

Page 54: ...1 9 Standard Amplitude Calibrator Frequency 1 kHz output amplitude 0 5 mV to 50 V peak to peak in a 1 2 5 step sequence amplitude accuracy 0 25 Tektronix calibration fixture 067 0502 00 recommended 10...

Page 55: ...width meets the specifica tions given in Section 1 Refer to complete procedure Performance Correct Incorrect list dis crepancies 11 Check Internal Trigger Jitter Page 5 8 Requirement No more than one...

Page 56: ...ajor dial setting between 1 00 and 9 00 Performance Correct Incorrect 24 Adjust 1 JUS Sweep Timing to Match Page 5 15 Delay Time Multiplier C530J 25 Check Delay Time Accuracy Page 5 15 Requirement Acc...

Page 57: ...rols Allow several minutes warmup before proceeding with calibration In the following steps whenever the B Hori zontal Mode is selected adjust the B Intensity to view the trace Whenever the A Horizont...

Page 58: ...b CHECK Remove the signal from the 7A16 Press the RESET button and check that the READY light is lit Reconnect the signal to the 7A16Aand check that the sweep runs one time Increase the A Intensity a...

Page 59: ...from the left vertical plug in to pin F on the External Input board and a 1 X probe from the right vertical plug in to pin H on the External Input board 7B71 Sine Wave Generator COUPLING SOURCE Frequ...

Page 60: ...30 Hz 0 3 div DC INT 30 Hz 0 3 div AC LF REJ INT 30 kHz 0 3 div AC HF REJ INT 50 kHz 0 3 div AC EXT 30 Hz 75 mV AC HF REJ EXT 30 Hz 75 mV DC EXT 30 Hz 75 mV AC LF REJ EXT 30 kHz 75 mV AC HF REJ EXT 5...

Page 61: ...Sweep Calibration SWP CAL a front panel adjustment a Set the 7B71 TIME DIV to 1 ms SOURCE to INT and TRIGGERING MODE to P P AUTO 7A16A Volts Div Coupling b Apply 1 ms markers from the 2901 time mark...

Page 62: ...eight divisions f INTERACTION Check steps 15 through 18 20 21 15 Check Adjust Magnifier Registration R795 b Position the middle marker to the center vertical line there are three markers on the total...

Page 63: ...lloscope not on the extender The 7B70 Test Time Base plug in may be removed and the 7B71 temporarily installed in the right B horizontal compartment If the 7B71 is placed in the B compartment set the...

Page 64: ...the right B horizontal compart ment not on the extender and set the controls as specified under Preliminary Control Settings except as follows 7B70 Removed from the oscilloscope Oscilloscope Horizont...

Page 65: ...display TABLE 5 8 7B71 on rigid extender 7B71 TIME DIV 2901 Markers Markers Div Allowable Error 02 Os 10 ns 1 cycle 5 div 0 13 div 5 div 05 Os 5 ns 1 0 2 div 1 Os 10 ns 1 2 Os 20 ns 1 5 Os 50 ns 1 1 O...

Page 66: ...portion starts at the tenth marker h Change the Oscilloscope Horizontal Mode to Alt and the 7B71 DELAY TIME MULTIPLIER to 1 00 d ADJUST Delay Start R590 left side forward of center so the intensified...

Page 67: ...MULT dial to read the number recorded in step i the intensified zone of the A Sweep trace should be near the tenth time mark 7B71 TIME DIV ns DELAY TIME MULT Near 1 00 7B70 Time Div 02 ns 7A16A Volts...

Page 68: ...rkers Rotate the DELAY TIME MULTIPLIER until the eleventh A Sweep time marker is intensified then rotate it slightly to position the nearest B Sweep marker to the center of the CRT c CHECK Jitter on t...

Page 69: ...I Centered on Positive Slope Norm AC Int Time Base XI Per Table 5 10 Fig 5 13 CRT display when checking sweep holdoff time c CHECK The holdoff time see Fig 5 13 corres ponds with the values given in T...

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Page 71: ...licon V Electron tube DS Indicating device lamp controlled rectifier Var Variable Elect Electrolytic P Connector movable portion VR Voltage regulator zener diode EMC electrolytic metal cased PMC Paper...

Page 72: ...46 00 Silicon CD12676 or FD3375 RELAYS K3 148 0035 00 Armature spdt 15V DC K6 148 0034 00 Armature dpdt 15V DC TRANSISTORS Q20A B 151 1009 00 Silicon FET N channel junction dual Q30 151 0221 00 Silico...

Page 73: ...2UF Cer 25V 80 20 C138 283 0079 00 O OluF Cer 250V 20 C141 281 0593 00 3 9pF Cer 500V 10 C147 281 0593 00 3 9pF Cer 500V 10 C150 281 0629 00 33pF Cer 600V 5 C152 281 0543 00 270pF Cer 500V 10 C156 281...

Page 74: ...lect 20V 20 C409 290 0523 00 2 2uF Elec t 20V 20 DIODES CR148 152 0153 00 Silicon FD7003 or CD5574 CR149 152 0153 00 Silicon FD7003 or CD5574 CR181 152 0322 00 Silicon A1108 CR182 152 0322 00 Silicon...

Page 75: ...N MPS918 Q171 151 0198 00 Silicon NPN MPS918 Q181 151 0223 00 Silicon 2N4275 Q182 151 0223 00 Silicon NPN 2N4275 Q220 151 0221 00 Silicon PNP 2N4258 Q221 151 0221 00 Silicon PNP 2N4258 Q224 151 0190 0...

Page 76: ...00 R135 315 0361 00 R136 315 0102 00 R141 323 0151 00 R142 315 0511 00 R143 321 0115 00 R144 321 0115 00 R145 315 0511 00 R147 323 0151 00 R148 315 0223 00 R149 315 0223 00 R150 315 0560 00 1 69K ohm...

Page 77: ...R233 315 0124 00 R234 315 0153 00 R235 315 0162 00 R239 307 0112 00 R241 315 0106 00 R243 315 0474 00 R244 315 0623 00 R246 315 0106 00 I No Disc Description 28 7 ohm 0 125W 1 383 ohm 0 50W 1 28 7 oh...

Page 78: ...315 0183 00 R335 315 0202 00 R336 315 0102 00 R339 315 0471 00 R340 315 0102 00 R341 315 0303 00 R342 315 0102 00 R343 315 0154 00 R344 315 0223 00 R346 315 0302 00 51 ohm 0 25W 5 3 09K ohm 0 125W 1 1...

Page 79: ...GRATED CIRCUITS U260 156 0049 00 Operational amplifier uA741C U267 156 0049 00 Operational amplifier uA74lC DIODES ZENER VR304 152 0140 01 Tunnel 10mA 8pF VR322 152 0125 00 Tunnel TD3A 4 7mA Tek Spec...

Page 80: ...4 00 315 0154 00 321 0356 00 321 0335 00 321 0344 00 315 0154 00 315 0160 00 Serial Model No Eff Disc See Mechanical Parts List for replacement parts Furnished as a unit with S530 Description Silicon...

Page 81: ...Pushbutton COUPLING 670 1169 05 TIME BASE Circuit Board Assembly CAPACITORS C404 283 0080 00 0 022UF Cer 25V 80 20 C407 283 0080 00 0 022UF Cer 25V 80 20 C421 283 0080 00 0 022UF Cer 25V 80 20 C431 2...

Page 82: ...Cer 200V 10 C799 290 0136 00 2 2uF Elect 20V 20 C801 290 0420 00 0 68UF Elect 75V 20 C803 290 0136 00 2 2uF Elect 20V 20 C805 290 0529 00 47uF Elect 20V 20 C807 290 0136 00 2 2uF Elect 20V 20 C809 28...

Page 83: ...No Eff Disc XB220000 REV B NOV 1974 _ Description Silicon similar to 1N4152 Silicon similar to 1N4152 Silicon similar to 1N4152 Silicon similar to 1N4152 Silicon similar to 1N4152 Silicon similar to 1...

Page 84: ...174 00 321 0246 00 315 0101 00 Description Silicon PNP 2N3906 Silicon PNP 2N3906 Silicon NPN 2N3904 or TE3904 Silicon NPN 2N3904 or TE3904 Silicon PNP 2N3906 Silicon NPN 2N3904 or TE3904 Silicon NPN 2...

Page 85: ...315 0123 00 R462 315 0752 00 R464 321 0271 00 R465 321 0234 00 R466 321 0277 00 R468 321 0306 00 R469 321 0209 00 R471 321 0271 00 R472 321 0193 00 R474 321 0150 00 R475 321 0215 00 R477 321 0219 00 R...

Page 86: ...22 ohm 0 25W 5 R537 315 0681 00 680 ohm 0 25W 5 R538 315 0330 00 33 ohm 0 25W 5 R539 315 0101 00 100 ohm 0 25W 5 R540 315 0622 00 6 2K ohm 0 25W 5 R541 315 0131 00 130 ohm 0 25W 5 R542 321 0259 00 4...

Page 87: ...00 R789 315 0472 00 R790 315 0433 00 R791 323 0272 00 R794 321 0228 00 R795 311 1230 00 R796 321 0289 00 R797 321 0289 00 R798 315 0510 00 R799 315 0101 00 910 ohm 0 25W 5 100 ohm 0 25W 5 I 6K ohm 0...

Page 88: ...nal amplifier UA741C DIODES ZENER VR573 152 0279 00 Zener 1N751A 0 4W 5 1V 5 VR576 152 0326 00 Zener 1N755A 0 4W 7 5V 5 670 1103 02 B DELAY MODE Circuit Board Assembly BULB DS490 150 0048 01 Incandesc...

Page 89: ...to circuit board Connection made to circuit board with interconnecting pin Pi Cl dibcuit boarct Blue tint encloses components located on circuit board The following prefix letters are used as referen...

Page 90: ...EXT TRIG IN OR E XT VOLTS iN TRlOGtR SIGNAL DELAY MOD6 CONTROL EXT SINGLE SWEEP RESET SWEEP NHlfc T 373 7B71 PLUG IM IS BLOCK DIAGRAM BLOCK DIAGRAM...

Page 91: ...EXT MAGNIFIER XI TIME DIV 1 ms B DELAY MODE INDEPENDENT DELAY TIME MULTIPLIER 0 00 POSITION Centered VARIABLE TIME DIV CAL IN The following control settings and connections were changed to obtain wav...

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Page 96: ...COUPLINS 270 1 I SOURCE S280 Kt3S RZ8Z K48 i K44 S FRONT PANEL SWITCHES e 2 0SOOO UP l VLB 73 7B71 PLUG IN 0 FRONT PANEL SWITCHES...

Page 97: ...TIME BASE GENERATOR...

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Page 100: ...DCPLtfc l s TO K48B lei 1 ISV StNOLE SWLLP MODE FROM R46I LIGHTS COMMON 6 S 4 S1G FROM QT8A EXT READY INDICATOR g FROM RAA A SV lights 5V ROW CURRENT WORD SCAN LINES AUX TRIG TR C TO 50V ISV ext singl...

Page 101: ...ad brass ig length or long THS truss head steel Fil HS fillister head steel OD outside diameter w wide or width Fig Index No Tektronix Part No Serial Model No Eff Disc Q t y Description 1 2 3 4 5 1 1...

Page 102: ...l connector 4 wire CONNECTOR terminal HOUSING light 3 button ATTACHING PARTS SCREW thread forming 2 x 0 375 inch PHS ATTACHING PARTS SCREW 1 72 X 0 25 inch 82 deg csk FHS CIRCUIT BOARD ASSEMBLY MODE T...

Page 103: ...66 1103 00 1 KNOB gray TIME DIV knob includes 213 0020 00 2 SETSCREW 6 32 x 0 125 inch HSS 44 366 1166 00 1 KNOB red VARIABLE CAL IN knob includes 213 0153 00 1 SETSCREW 5 40 x 0 125 inch HSS 45 670 1...

Page 104: ...NUT hex 0 25 32 x 0 312 inch WASHER flat 0 141 ID x 0 50 inch OD LINK terminal connector TERMINAL pin 1 15 inches long TERMINAL pin 0 67 inch long TERMINAL pin 0 365 inch long HOLDER variable resisto...

Page 105: ...136 0366 00 B226150 1 SOCKET 6 pin 136 0350 00 B226150 2 SOCKET 3 pin 200 0945 00 1 COVER half transistor temp stabilizer 200 0945 01 1 COVER half transistor tenp stabilizer dual threaded 211 0062 00...

Page 106: ...front SUBPANEL front ATTACHING PARTS SCREW thread forrming 6 32 x 0 50 Fil HS PANEL rear ATTACHING PARTS SCREW thread forming 6 32 x 0 50 Fil HS SPACER sleeve 0 10 inch SHIELD electrical SHIELDING GAS...

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Page 108: ...AL instruction B205000 up 7B71 DELAYING TIME BASE B205000up REPACKAGING Fig Index Tektronix Seriat Model No No Part No Eff Disc 2 065 0125 00 1 004 0241 00 2 004 0242 00 3 004 0243 00 4 004 0748 00 Q...

Page 109: ...mediately into printed manuals Hence your manual may contain new change information on following pages A single change may affect several sections Sections of the manual are often printed at different...

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Page 111: ...1 Tent S N ELECTRICAL PARTS LIST CORRECTION ADD Ferromic supjwessicai b acl 27 1 0507 00 on one leg of Cl 3 Location Trigger Amplifier Board 670 T 136 04 05 7B70 Trigger Amplifier 0 1141 03 04 Board 7...

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Page 113: ...ES iiterpage circuit BOARR C535 R335 CHA NGE TO G520 283 0028 00 CaDacitor ceramic 0022uP disc Value between 6 8K and 82K TINTS Bv SE CIRCUIT BOARD 281 0542 00 Capacitor ceramic 18 pp tub S530 ssiok S...

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