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NSTRUCT ON MANUAL erial Number __________ ektronix, Inc. S.W. Millikan Way • P. O. Box 500 • Beaverton, Oregon • Phone Ml 4-0161 • Cables: Tektronix 070-382...
WARRANTY ll Tektronix instruments are warranted against defective materials and workman ship for one year. Tektronix transformers, manufactured in our own plant, are war ranted for the life of the instrument. ny questions with respect to the war ...
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CONTENTS Section Characteristics Section Operating Instructions Section Circuit Description Section Maintenance Section Calibration Procedure Section 6 Parts List and Schematic Diagrams...
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2 volts General peak-to-peak from 0.1 mv/cm, to .2 v/cm, 20 volts peak-to- The Tektronix Type 502 Oscilloscope provides linear peak from .5 v/cm to 2 v/cm, and 200 volts peak-to-peak dual-beam displays with a wide range of sweep rates com ...
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Characteristics — Type 502A nput characteristics at TR GGER NPUT connector Graticule Edge lighted — marked in 10 vertical and 10 horizontal C coupled — 1 megohm in series with 0.01 μ f. 1 cm divisions with 2 mm markings on the baselines.
SECT ON 2 OPER TING INSTRUCTIONS Shipping Blocks a thermal cutout switch will disconnect the power and keep it disconnected until the temperature drops to a sofe value. It is very important to remove the shipping blocks from For proper air circulation, the bottom and side panels the vertical amplifier prior to using the oscilloscope.
Operating nstructions — Type 502A Fig. 2-2. The power transformer has two extra windings permitting nominal primary voltages of 110, 117, 124, 220, 234 or 248 volts, 50 or 60 cycle operation. Fan Connections nput Selection The manner in which the fan is wired depends on the line...
Operating nstructions — Type 502A nput Connections Here are some precautions you should observe in connect ing your oscilloscope to the signal source: void errors in readings due to stray electric or magne coupling between circuits, particularly leads connected to the input connector.
Operating nstructions — Type 502A Fig. 2-6. Location of locking sleeve and knurled parts on the Type P6006 Probe. the probe body until a flat top is obtained on the square The following instructions tell you how to select the wave waveform.
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Operating nstructions — Type 502A gering will normally be used when you are observing a AC Coupling waveform which bears a fixed time relationship to the power C coupling is selected in the LINE, LOWER C, UPPER line frequency.
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Operating nstructions — Type 502A Note: n this illustration of the TR GGER NG LEVEL control, the AUTOMAT C and RECURRENT positions are not shown. The “ Higher Region ’ ’ and “ Lower Region ” shown do not actually appear on the front panel, but refer to the relative graticule position at which triggering occurs.
Operating nstructions — Type 502A Magnified sweep rates are all calibrated within 3% ac Magnifier curacy so long as their true time per centimeter is 1 mico- To expand a particular part of the display horizontally, second or more.
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Operating nstructions — Type 502A ponent voltage measurements. reference line must be es How to measure the ac component of a wave tablished on the c rt screen. The actual voltage measurement form is taken with respect to this reference line.
Operating nstructions — Type 502A (Do not adjust the vertical positioning control after this reference point has been established.) 3. Remove the probe tip from ground and connect the probe to the signal source. djust the TRIGGERING LEVEL Control for a stable display.
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Operating nstructions — Type 502A It may be necessary to readjust the INTENSITY B L NCE If the trace shifts slightly between the different ranges of the SENSITIVITY Control this may be cured by a very slight Control each time the setting of the INTENSITY Control is changed.
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Operating nstructions — Type 502A tube sockets. Before connecting the resistors to the leads from the amplifier, slip a piece of insulated sleeving (spa ghetti) over the wire. Then, after making the connections, CUPS TO DEFLECT ON PLATE P NS draw the sleeving back over the insulated resistor pigtail.
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Operating nstructions — Type 502A TR GGER SELECTOR — TR GGER NG LEVEL — Determines whether trig Selects the voltage point gering occurs on the triggering wave rising portion form where the sweep MODE — Provides means Slope) or falling por ...
SECT ON 3 CIRCUIT DESCRIPTION ntroduction The sensitivity of the Vertical mplifier, as mentioned previously, is 100 microvolts per centimeter. However, by The Type 502 is a dual-beam, high-gain, low frequency means of attenuation and degeneration networks, the vertical oscilloscope employing a T5021 type dual-gun cathode-ray deflection factor can be increased to 20 volts per centimeter.
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Circuit Description — Type 502A Fig. 3-1. Simplified Upper and Lower Beam Vertical Amplifiers.
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Circuit Description — Type 502A (or C440 for Input B) plus the tube and stray capacitance. mplifier stage. Conversely, the less the shunting of R408 C410 is then adjusted so that the total input capacitance the greater the values of R408 and the smaller the gain of is 47 pf.
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Circuit Description — Type 502A R424 provides additional differential balance for the low- DC TRIG Control R495 is adjusted to set the cathode volt sensitivity ranges, and is most effective when the SENSI age to zero when triggering with DC coupling and with the TIVITY switch is in the .2 VOLTS PER CM position.
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+ 35OV VI6IB > UNBLANKING VI35B + IOOV sawtooth ------------ ► to horiz amp + IOOV VI45A + IOO V (TIME BASE TRIG DIAG) NORMAL (X ) TIME BASE AMP UPPER BEAM AMP SWEEP MAG POS T ONS -I50V 150 V -I5OV -I5OV...
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Circuit Description — Type 502A for the voltage at the grid of V45B to rise exponentially from at the plate of V45 to rise, which in turn will complete its starting point, below cutoff, to a point where plate current the negative step-voltage output from the Trigger Multivi ...
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Circuit Description — Type 502A voltage, and the voltage at the plates of the Disconnect the Hold-Off allows a finite time for the Time-Base circuits Diodes, moves negative. This cuts off the diodes. to regain a state of equilibrium after the completion of a sweep.
Circuit Description — Type 502A The negative going trigger pulse when it arrives will Input mplifier cathode-coupled paraphase cause V135 to go into cutoff and V145 to come into amplifier, and converts the positive-going sawtooth voltage, conduction. The action of the Sweep Generator circuit as...
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Circuit Description — Type 502A supplies have their own regulation circuits. In addition to emitter of Q644 will also go more negative since it is strapped directly to the output. The collector of Q644 the three main power supplies, a transistorized full-wave...
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Circuit Description — Type 502A network composed of R864, C868, C869 and R868 for one AMPL TUDE CAL BRATOR grid circuit, and R864, C866, C867 and R866 for the other, MPLITUDE C LIBR TOR is a square-wave gen is employed. By this arrangement, the fast leading edge of...
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Under normal operating conditions the filter you prefer, you can order the solder directly from Tektronix should be inspected and cleaned if necessary every three in one pound rolls. Order by Tektronix part number 251-514. to four months. More frequent inspection is required when the operating conditions are more severe.
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Maintenance — Type 502A 1. Use a soldering iron of about 75-watt rating. 2. Prepare the tip of the iron as shown in Fig. 4-1. 3. Tin only the first 1/16 to 1/8 inch of the tip. For soldering to ceramic terminal strips tin the iron with solder containing about 3% silver.
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Maintenance — Type 502A sockets; if this procedure is followed less recalibration of the instrument will be required upon completion of the servicing. When replacing any tube in the instrument, check first to see that components through which the tube draws current have not been damaged.
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Maintenance — Type 502A On the other hand, the crt display can often be used to isolate trouble to one particular circuit when trouble ob viously exists in that circuit. If there is no vertical deflection, for example, when the intensity and horizontal deflection...
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Maintenance — Type 502A f the output voltage is high with excessive ripple, check: 1. For high line voltage 2. The amplifier tubes and transistors (V746, V666, V636, Q644, and Q634) 3. For insufficient loading f the output voltage is high with normal ripple, check: 1.
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Maintenance — Type 502A the short is removed, the vertical amplifier is in a state of d c the input stage. When you reach a point where the spot unbalance. To determine the cause of this condition, short does not return to the screen, the stage immediately following the plates of the output stage (V474B and V484B) together.
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Maintenance — Type 502A vary between approximately 34 and 135 volts. n incorrect Low frequency distortion is usually caused by a change in the time constant of the input coupling circuit. If tubes voltage range indicates a defective trigger input amplifier or become gassy, their resultant grid current will establish a TRIGGERING LEVEL Control.
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Maintenance — Type 502A Next, measure the grid to cathode voltage of the Hold- Single Sweep will not perform properly Off Cathode Follower, V183 and V145B. Both of these If D126 opens, the Time-Base Generator will still operate readings should be approximately — 4 volts if the cathode normally when the MODE switch is in the NORM L position.
Each numbered step contains the information required to make one adjustment or a series of related Fig. 5-1. Tools required for calibrating the Type 502A Oscilloscope. adjustments. In each calibration step only the required information is ccurate rms-reading ac voltmeter, 0-150 volts (0-250 given.
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Calibration Procedure — Type 502A 13. Coaxial "Straight" Connector. (1) NOMIN L RESIST NCES OF POWER SUPPLIES 14. Jumpers, 6 inch with banana plugs. (3) SUPPLY PPROX. RESIST NCE TO GROUND constant amplitude sine-wave generator having output frequencies of 1 kilocycle, 50 kilocycles, 100 kilocycles, 200 -150V 3.5 k...
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Calibration Procedure — Type 502A graticule, then tighten the clamp. Now with the red knob, Using the test oscilloscope, check the ripple voltage at near the bottom of the clamp, rotate the crt until the trace the output of each power supply when the autotransformer runs parallel to the horizontal lines of the graticule.
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Calibration Procedure — Type 502A Fig. 5-4. Adjustment of the GEOM control. n waveform A the GEOM control is improperly set causing bowing of the vertical lines. waveform B the bowing of the vertical lines has been reduced to a minimum by the proper adjustment of the GEOM control.
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Calibration Procedure — Type 502A djustment of the faster sweep rates is indicated in the 10. NORM MAG REG S chart below. The 1 μ SEC and the 5 μ SEC timing adjustments Turn the TRIGGERING LEVEL to RECURRENT and place will interact and therefore will have to be rechecked several the HORIZONT L DISPL Y switch in the X20 position.
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Calibration Procedure — Type 502A 15. Gas and Hum Check -DC position and the SENSITIVITY switch in the .2 VOLTS PER CM position. Set the .2V/CM G IN for 2.5 centimeters With jumpers, ground both the inputs and set the SENSI ...
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Calibration Procedure — Type 502A 19. .2MV/CM GA N R462 C469 pply a .5 millivolt signal from the calibrator to input of the vertical amplifier. Place the SENSITIVITY switch in the .2 mVOLTS PER CM position. Set the .2MV/CM G IN control for 2.5 centimeters of vertical deflection.
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Calibration Procedure — Type 502A 24. Setting GA N ADJ FOR HOR Z MODE The vertical line may be used to determine the amplitude of the input signal. Turn the HORIZ DEF PL TE SELECTOR to the UPPER Once the proper amplitude has been determined, turn...
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Calibration Procedure — Type 502A Place the SENSITIVITY switch in the 2 VOLTS PER CM Checking Min. Initial SENSITIVITY position and adjust the Type 105 output for approximately for Proper Freq . and Freq. Setting 3 cm of vertical deflection.
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Calibration Procedure — Type 502A 29. FEEDBACK BAL 31. STAB L TY ADJUST Set the TIME/CM switch of the Type 502 to 2 mSEC; the Disconnect the Calibrator signal, remove the jumper from Input Selector to B-DC and the SENSITIVITY switch to .2...
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Calibration Procedure — Type 502A position the lower trace under the lower horizontal center- 35. Single Sweep Check line. Set the DC TRIG Control so that the sweep triggers properly on both the + and — settings of the TRIGGER Reset the following controls: SELECTOR Slope Switch.
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GEOM C311 AST G UPPER NORM/MAG X20 CAL REG S Fig. 5-14. Top view, Type 502A. .2 MV/CM GA N DC TR G FEEDBACK BAL HOR Z DEF PLATE SELECTOR SW TCH HOR Z BEAM REG S CRT Alignment Clamp...
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FEEDBACK BAL 2MV/CM GA N C469 C440 --------- 2V/CM GA N C410 — ■ - DC TR G 2MV/CM D FF BAL R429 C406C C407A C407C C406A C406G C406J C407G 2V/CM D FF BAL Fig. 5-17. Bottom view, Type 502A. 5-13...
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If a part you have ordered has been replaced with a new or improved part, your local Tektronix Field Office will contact you concerning any change in part number. ABBREV AT ONS AND SYMBOLS...
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FRONT SE IAL NO. PA T NO. EFF. DISC. DESC IPTION 333-748 PANEL, front 004-174 COVE , panel, plastic 387-785 PLATE, subpanel, front, alum. 358-010 BUSHING, alum. 3/8-32 x 9/16 in. anodized LOCKWASHE , steel, internal 3/8 x 11/16 in. 210-013 NUT, hex, alum.
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Parts List — Type 502A FRONT SER AL NO. REF. PART DESCR PT ON EFF. D SC. 366-148 KNOB, charcoal NUT, hex, brass, 3/8 -32 x '/ 2 in. 210-413 210-840 W SHER, steel, .390 I D x 9/16 in. OD 210-013 LOCKW SHER, steel, internal 3/8 x 11/16 in.
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Parts List — Type 502A LEFT S DE SER AL/MODEL NO. REF. PART DESCR PT ON EFF. D SC. SOCKET, 14 pin 136-019 RING, clamping assembly 354-103 RING, CRT securing (not shown) 354-178 SCREW, 6-32 x 1 in. RHS 211-560 NUT, hex, brass, 6-32 x } /s, in.
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Parts List — Type 502A LEFT S DE SER AL NO. REF. PART DESCR PT ON EFF. D SC. SWITCH, INPUT SELECTOR "B", wired 262-190 Includes: 343-006 CL MP, cable, '/ 2 in. plastic SCREW, 6-32 x y 2 in. BHS 211-511 W SHER, steel, 6L x % in.
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Parts List — Type 502A LEFT S DE SER AL/MODEL NO. REF. PART DESCR PT ON EFF. D SC. 426-046 MOUNT, fan motor, 5-y 2 in. 348-008 SHOCKMOUNT, rubber, solid round, '/ 2 in. dia. x ’ / 2 in. high...
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Parts List — Type 502A R GHT S DE SER Al/MODEl NO. REF. PART DESCR PT ON EFF. D SC. SCREW, thread cutting, 6-32 x % in. truss HS, phillips 385-135 213-041 SCREW, thread cutting, 6-32 x % in. truss HS, phillips 376-007 COUPLING, 1 in.
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Parts List — Type 502A R GHT S DE SER AL NO. REF. PART DESCR PT ON EFF. D SC. 337-256 SHIELD, V. . chassis, alum. 3-'/ 4 x 5- 7 / 14 x ’ / 2 in. 211 -507 SCREW, 6-32 x 5 / 16 in.
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Parts List — Type 502A SER AL NO. REF. PART DESCR PT ON EFF. D SC. SOCKET, graticule light with ground lug 136-035 SCREW, 6-32 x 5 / 16 in. PHS, with lockwasher 211 -534 W SHER, steel, 6L x % in.
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Parts List — Type 502A SER AL NO. REF. PART DESCR PT ON EFF. D SC. SOCKET 136-008 SCREW, thread cutting, 5-32 x 3 / 16 in. Pan H steel, phillips 213-044 GROMMET, rubber, ’ / 2 in. 348-005 CL MP, #20 wire for neon bulbs 343-043 STRIP, ceramic, 3 / 4 in.
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Parts List — Type 502A BOTTOM SER AL NO. REF. PART DESCR PT ON EFF. D SC. SHIELD, alum. 1-% x ’ / 2 in. 337-237 LOCKW SHER, steel, internal #4 210-004 NUT, hex, brass, 4-40 x 3 / 16 in.
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Parts List — Type 502A BOTTOM SER AL/MODEL NO. REF. PART DESCR PT ON EFF. D SC. 210-202 LUG, solder, SE6 with 2 wire holes 211-504 SCREW, 6-32 x % in. BHS 210-407 NUT, hex, brass, 6-32 x ’ / 4 in.
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Parts List — Type 502A REAR SER AL/MODEL NO. PART REF. DESCR PT ON EFF. D SC. PL TE, rear overlay, alum. 387-786 PL TE, subpanel, rear, alum. 387-787 SCREW, thread forming #6 x % in. THS, phillips 213-104 PL TE, brass, ’ /| 4 xl- ’ / 32 in. ground plated, open end...
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Parts List — Type 502A CAB NET SER AL NO. REF. PART DESCR PT ON EFF. D SC. 387-055 PL TE, cabinet side left, textured blue vinyl Includes: F STENER, latch assembly 214-057 Consisting of: (each) 210-480 NUT, nylon, large with insert 213-033 SCREW, steel, '/ 2 x '/ 2 x 8-32 in.
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Parts List — Type 502A ACCESSOR ES SER AL/MODEL NO. REF. PART DESCR PT ON EFF. D SC. 378-539 FILTER, polarized light, 5- ” / 16 x 5- n /i« in. 012-031 CORD, patch, banana plug both ends, 18 in. red...
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Parts List — Type 502A ELECTR CAL PARTS L ST Values are fixed unless marked Variable. Tektronix Ckt. No. Part Number S/N Range Description Bulbs B 1 24 150-027 Neon, Type NE-23 RE DY B 1 67 150-027 Neon, Type NE-23...
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Parts List — Type 502A Capacitors (continued) Tektronix Ckt. No. Part Number Description S/N Range C400 † matched within *295-066 .1 μf 600 v C401 † 1 % of each other C406 † 281-012 7-45 pf Cer. Var. C406C †...
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Parts List — Type 502A Capacitors (continued) Tektronix Ckt. No. Part Number Description S/N Range C800 285-501 .001 μf 600 v C805 285-510 .01 μf 400 v C807 283-538 .003 μf Mica 500 v C808 use 283-022 .02 μf Disc Type...
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Parts List — Type 502A Resistors (continued) Tektronix Ckt. No. Part Number S/N Range Description 302-124 120 k ½ W 302-101 100 Ω ½ W 304-473 47 k 311 -005 Ω TRIG. LEVEL CENT. Var. 302-333 33 k ½ W 302-101 100 Ω...
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Parts List — Type 502A Resistors (continued) Tektronix Ckt. No. Part Number S/N Range Description R166 306-154 150 k R1 67 302-155 1.5 meg ½ W R168 302-473 47 k ½ W R1 69 302-101 Ω ½ W R174 306-273 27 k R1 76 311-016 SWP.
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Parts List — Type 502A Resistors (continued) Tektronix Ckt. No. Part Number S/N Rarje Description R383 301-204 200 k ½ W R385 302-223 22 k ½ W R386 302-223 22 k ½ W R391 309-052 220 k ½ W Prec. R393 301-204 200 k ½ W...
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Parts List — Type 502A Resistors (continued) Tektronix Ckt. No. Part Number Description S/N Range R428 † 309-432 82.5 k ½ W Prec. R429 † 311-017 10 k .1 W Var. V R. DC B L. R433 † 311-243 50 k Var.
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Parts List — Type 502A Resistors (continued) Tektronix Ckt. No. Part Number S/N Range Description R488 † 311-120 2.5 k .2 W Var. .2 V/CM G IN R489 311-067 G IN DJ. FOR HORIZ. MODE .2 W Var. R490 302-683 68 k ½ W...
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Parts List — Type 502A Resistors (continued) Tektronix Ckt. No. Part Number Description R685 302-101 Ω ½ W ½ W R686 302-101 Ω R722 302-104 100 k ½ W R739 302 102 ½ W R740 302-273 27 k ½ W 470 k ½ W R741 302-474...
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Parts List — Type 502A Resistors (continued) Tektronix Ckt. No. Part Number Description S/N Range R858 306-156 15 meg R859 306-156 15 meg R860 311-397 2 meg Var. INTENSITY B L. R861 304-105 1 meg R862 311-397 2 meg Var.
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Parts List — Type 502A Transformers Tektronix S/N Range Ckt. No. Part Number Description T602 *120-117 L. V. Power T801 *120-150 H. V. Power Transistors Q 1 24 151 -093 2N2043 Q634 151-004 2N214 Q644 151-004 2N214 Q647 Use 151-137...
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Parts List — Type 502A Electron Tubes (continued) Tektronix S/N Range Ckt. No. Part Number Description V822 154-051 5642 V832 154-051 5642 T5021-2 CRT Standard Phosphor V859 *154-246 V862 154-051 5642 V873 154-078 6 N8 V875 154-022 6 U6 6-32...
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C RCU T NUMBERS THRU TR IGGER TIME-BASE...
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-I5OV PJ as 41 K. W VEFORMS 4 VOLT GE RE DINGS WERE OBTAINED WITH CONTROLS BETAS FOLLOWS: -15OV HORIZONTAL DISPLAY ......... NORMAL TRIGGER SELECTOR ........- EXT., DC TIME/CM • • •............I MILLISEC ^ENT TRIGGERING LEVEL 2 FOR WAVEFORMS ..........
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T M NG T M NG RES 5TORS CAPAC TORS TYPE 502 OSCILLOSCOPE...
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HOLD-OFF CAPAC TORS T M NG 4 RES STORS CAPAC TORS SW 6O TIMING SWITCH...
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WITH CONTROLS SET AS FOLLOWS: HORIZONTAL DISPLAY NORMAL TRIGGER SELECTOR — EXT., DC TRIGGERING LEVEL FULL LEFT BUT NOT SWITCHED TO AUTOMATIC HORIZONTAL POSITIONS FOR LOWER VOLTAGE READINGS FULL RIGHT FOR UPPER VOLTAGE READINGS FULL LEFT TYPE 502A OSC LLOSCOPE...
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OUTPUT INPUT AMPL F ER AMPLIFIER CIR.CUIT NUMSER.5 300 THR.U 399...
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L ______________________ CHANNEL A _____________________ J L ______________________ CHANNEL E> ATTENUATOR ATTENUATOR TYPE. 5O2 OSCILLOSCOPE...
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NPUT AMP. SECOND AMP. READ NGS WERE WITH CONTROLS SET AS FOL INPUT SIGNAL ......SENSITIVITY ......VERTICAL POSITION: FOR LOWER. VOLTAGE READINC FOR UPPER VOLTAGE READIH< TYPE 5O2A OSCILLOSCOPE...
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SECOND AMP. DRJVEp. CF*S OUTPUT AMP. + 350V + 85OV R.474 V474A %/2A 7 TO LOWER. ‘ DEFLECTION PLATE V474B 5 +IOOV k/2A77 TO LEFT HAND DEFL PLATE 4-102 THRU SW489-2R- (HORlZ AMP DIA6) ■» V454 6AU6 SW 469 C470 HORiz DEFL PLATE SELUTORl ALSO SEE HOR Z AMP...
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HE TER WIRING DI GR M TYPE 5O2A OSCILLOSCOPE...
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POWER SUPPLY [C RCU T NUMBERS 600, THRU 799...
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VOLTAGE READ NGS WERE OBTA NED W TH CONTROLS SET AS FOLLOWS: INTENSITY • • • FULk. LEFT SEE P RTS LIST FOR E RLIER V LUES ND SERI L NUMBER R NGES OF P RTS M RKED WITH BLUE OUTLINE. TYPE 5O2A OSC LLOSCOPE...
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CA.L Bp-A.TOp. MULT V BP-A.TOR. + IOOV TYPE 5O2 OSCILLOSCOPE...
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CAL.OUT CF C LIBR TOR. C RCU T NUMBERS 8~7O THRU 899 4Z£...
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MANUAL CHANGE NFORMAT ON t Tektronix, we continually strive to keep up with latest electronic developments by adding circuit and component improvements to our instruments as soon as they are developed and tested. Sometimes, due to printing shipping require ...
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YPE 5 0 2A — EN . S/N 2343 0 PAR S LIS CORREC ION CHANGE V152 157- 0104 - 01 Selected 6AL5 M913U/665...
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