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TM 9-6625-646-14&P TECHNICAL MANUAL OPERATOR, ORGANIZATIONAL, DIRECT SUPPORT, AND GENERAL SUPPORT MAINTENANCE MANUAL (INCLUDING REPAIR PARTS) FOR
OSCILLOSCOPE, TEKTRONIX, MODEL 212 NSN 6625-01-061-5519
MULTIPLE LAUNCH ROCKET SYSTEM
DEPARTMENT OF THE ARMY JUNE 1984
TM 9-6625-646-14&P WARNING DANGEROUS VOLTAGE is used in the operation of this equipment DEATH ON CONTACT may result if personnel fail to observe safety precautions
Never work on electronic equipment unless there is another person nearby who is familiar with the operation and hazards of the equipment and who is competent in administering first aid. When the technician is aided by operators, he must warn them about dangerous areas. Whenever possible, the power supply to the equipment must be shut off before beginning work on the equipment. Take particular care to ground every capacitor likely to hold a dangerous potential. When working inside the equipment, after the power has been turned off, always ground every part before touching it. Be careful not to contact high-voltage connections when installing or operating this equipment. Whenever the nature of the operation permits, keep one hand away from the equipment to reduce the hazard of current flowing through vital organs of the body.
WARNING Do not be misled by the term "low voltage." Potentials as low as 50 volts may cause death under adverse conditions. COMMON and probe ground straps are electrically connected. Therefore, an elevated reference applied to any is present on each - as indicated by the yellow warning bands under the probe retractable hook tips. For Artificial Respiration, refer to FM 21-11.
EXTREMELY DANGEROUS POTENTIALS greater than 500 volts exist in the following units: 1. CRT Power Supply 2. Horizontal Deflection System 3. Vertical Deflection System
a/(b blank)
TM 9-6625-646-14&P
Copyright 1972 by Tektronix, Inc. All rights reserved. REPRODUCED BY PERMISSION OF TEKTRONIX, INC. Distribution is limited to use in connection with the Multiple Launch Rocket System.
Technical Manual No. 9-6625-646-14&P
HEADQUARTERS DEPARTMENT OF THE ARMY Washington, D.C., 8 June 1984 Operator's, Organizational, Direct Support, and General Support Maintenance Manual (Including Repair Parts) for OSCILLOSCOPE, TEKTRONIX, MODEL 212 (NSN 6625-01-061-5519) MULTIPLE LAUNCH ROCKET SYSTEM
REPORTING OF ERRORS You can help improve this bulletin by calling attention to errors and by recommending improvements and stating your reasons for the recommendations. Your letter or DA Form 2028, Recommended Changes to Publications, should be mailed directly to Commander, U.S. Army Missile Command, ATTN: DRSMISNPM, Redstone Arsenal, AL 35898. A reply will be furnished to you. TABLE OF CONTENTS Page iii 0-1 0-1 0-1 1-1 1-4 1-5 1-6 1-7 2-1 3-1 3-1 3-1 3-1 3-2 3-2
LIST OF ILLUSTRATIONS............................................................................................................................ SECTION 0. GENERAL INFORMATION .......................................................................................... Scope............................................................................................................................ Indexes of publications ................................................................................................. INTRODUCTION .......................................................................................................... Option information ........................................................................................................ Accessories .................................................................................................................. Manual change information .......................................................................................... Calibration test equipment replacement ....................................................................... FUNCTIONS OF CONTROLS AND CONNECTORS .................................................. PREVENTIVE MAINTENANCE.................................................................................... Disassembly instructions .............................................................................................. Cleaning........................................................................................................................ Visual inspection ........................................................................................................... Semiconductor checks ................................................................................................. Recalibration .................................................................................................................
SECTION
1.
SECTION SECTION
2. 3.
This manual is, in part, authenticated manufacturer's commercial literature. A Maintenance Allocation Chart and Recommended Spare Parts List has been added to supplement the commercial literature. The format of this manual has not been structured to consider levels of maintenance.
i
TM 9-6625-646-14&P SECTION 4. CALIBRATION ................................................................................................................ Test equipment required................................................................................................. Preliminary procedure..................................................................................................... Preliminary control settings............................................................................................. Procedure ....................................................................................................................... TROUBLESHOOTING AIDS .......................................................................................... Component color-code ................................................................................................... Semiconductor lead configurations ................................................................................ Equipment recommended .............................................................................................. CIRCUIT DESCRIPTION................................................................................................ Block ............................................................................................................................... Circuit operation.............................................................................................................. CORRECTIVE MAINTENANCE ..................................................................................... Obtaining replacement parts........................................................................................... Component replacement ................................................................................................ Instrument repackaging .................................................................................................. PARTS LIST, DIAGRAMS AND CIRCUIT BOARD ILLUSTRATIONS .......................... Electrical parts list........................................................................................................... Mechanical parts list ....................................................................................................... Exploded drawings.......................................................................................................... Circuit board drawings and schematics .......................................................................... REFERENCES ........................................................................................... MAINTENANCE ALLOCATION CHART (MAC) ......................................... RECOMMENDED REPAIR PARTS LIST................................................... 4-1 4-1 4-3 4-3 4-4 5-1 5-1 5-2 5-2 6-1 6-1 6-1 7-1 7-1 7-1 7-4 8-1 8-2 8-12 8-17 8-19 A-1 B-1 C-1
SECTION
5.
SECTION
6.
SECTION
7.
SECTION
8.
APPENDIX A. B. C.
ii
TM 9-6625-646-14&P LIST OF ILLUSTRATIONS
Figure
1-1 1-2 2-1 3-1 3-2 4-1 4-2 4-3 4-4 4-5 5-1 5-2 6-1 6-2 6-3 6-4 6-5 7-1 7-2
Title
212 Oscilloscope. 212 Oscilloscope Accessories. Side Panel Controls and Connectors. Location of Screws Securing Bottom Cover and Side Panel. Location of Circuit Boards Within the 212. Location of Power Supply Test Points and CRT Grid Bias Adjustment. Location of Trace Rotation Adjustment. Location of Vertical Centering Adjustment and Test Point. Location of Attenuator Compensation Capacitors. Location of Horizontal Centering Adjustment and Test Point. Color Code for Resistors, Ceramic Capacitors, and Dipped Tantalum Electrolytic Capacitors. Lead Configuration of Semiconductors Used in this Instrument. Vertical Input Amplifiers Detailed Block Diagram. Vertical and Horizontal Output Amplifiers Detailed Block Diagram. Trigger/Sweep Generator Detailed Block Diagram. Power Supply Detailed Block Diagram. CRT Circuit Detailed Block Diagram. Selecting C210 and C212 Capacitance Values for 48 to 52 Hz Operation. Selecting C210 and C212 Capacitance Values for 58 to 62 Hz operation. Mechanical Parts, Exploded View. Block Diagram. Al Input Circuit Board (Front). Al Input Circuit Board (Near). Waveform Conditions - Vertical Amplifier. Vertical Amplifier Schematic Diagram. Vertical Amplifier Schematic Diagram. A2 Amplifier Circuit Board. Waveform Conditions - Horizontal and Vertical Output Sweep and Trigger. Horizontal and Vertical Output Sweep and Trigger Schematic Diagram. A3 Power Supply Circuit Board, SN B040000-up. A3 Power Supply Circuit Board, below SN B040000. CRT Circuit Schematic Diagram. Power Supply Schematic Diagram.
Page
0-1 1-5 2-1 3-1 3-2 4-4 4-4 4-5 4-7 4-10 5-1 5-2 6-2 6-3 6-4 6-5 6-6 7-2 7-3 8-17 8-19 8-21 8-21 8-23 8-23 8-25 8-25 8-27 8-27 8-29 8-31 8-33 8-35
8-0 8-1 8-1A 8-1B 8-1C 8-1D 8-1E 8-2 8-2A 8-2B 8-3A 8-3B 8-4 8-5
iii
TM 9-6625-646-14&P SECTION 0 GENERAL INFORMATION
O-1. Scope. This manual contains instructions for the operator, organizational, direct support, and general support maintenance of and calibration procedures for Tektronix Oscilloscope, Model 212. Throughout this manual, Tektronix Oscilloscope, Model 212 is referred to as the 212. O-2. Indexes of Publications. a. DA Pam 310-4. Refer to the latest issue of DA Pam 310-4 to determine whether there are new editions, changes, or additional publications pertaining to Tektronix Oscilloscope, Model 212. b. DA Pam 310-7. Refer to the latest issue of DA Pam 310-7 to determine whether there are modification work orders (MWO's) pertaining to Tektronix Oscilloscope, Model 212. O-3. Forms, Records, and Reports. Department of Army forms and procedures used for equipment maintenance and calibration are those prescribed by TM 38-750, The Army Maintenance Management System. Accidents involving injury to personnel or damage to materiel will be reported on DA Form 285, Accident Report, in accordance with AR 385-40.
O-4. Reporting Equipment Improvement Recommendations (EIR). If your 212 needs improvement, let us know. Send us an EIR. You, the user, are the only one who can tell us what you don't like about your equipment. Let us know why you don't like the design. Tell us why a procedure is hard to perform. Put it on an SF 368 (Quality Deficiency Report). Mail it to Commander, U.S. Army Missile Command, ATTN: DRSMI-SNEM, Redstone Arsenal, AL 35898. We'll send you a reply. O-5. Administrative Storage. To prepare the Tektronix Oscilloscope, Model 212 for placement into and removal from administrative storage, refer to Section 3, Chapter 4, AR 750-25-1, Maintenance of Equipment and Supplies. Temporary storage should be accomplished in accordance with TB 750-25-1, Section 2, Maintenance of Supplies and Equipment. O-6. Destruction of Army Electronics Materiel. Destruction of Tektronix Oscilloscope, Model 212 to prevent enemy use shall be in accordance with TM 430002-26, Organizational Maintenance Manual, Destruction of Equipment to Prevent Enemy Use for Launcher, Rocket, Armored Vehicle Mounted: XM270, Multiple Launch Rocket System.
0-1
TM 9-6625-646-14&P
Figure 1-1. 212 Oscilloscope.
0-2
TM 9-6625-646-14&P SECTION 1 INTRODUCTION The 212 Oscilloscope is a dual-channel portable oscilloscope using all solid state and integrated circuitry (except the CRT). The small size of the 212 makes it an extremely portable oscilloscope for on-location maintenance in many fields of application. The 500 kilohertz vertical system provides vertical deflection factors from one millivolt (at a reduced bandwidth) to 50 volts/division at the tip of either of the two integral high-impedance probes. Both single-trace and dualtrace modes of operation are offered. Singletrace displays are achieved by turning off either vertical channel with its position control. In the dual-trace mode, the instrument automatically chops or alternates, depending upon the sweep rate. The trigger circuits provide stable triggering over the full bandwidth capabilities of the vertical system. The horizontal deflection system provides calibrated sweep rates from 500 milliseconds to five microseconds/ division. It also provides uncalibrated sweep rates, via a variable sweep magnifier, to at least five times the indicated sweep rate for a maximum of at least one microsecond/ division. In addition, X-Y operation is provided. Channel 1 supplies the horizontal (X) deflection, with a range from less than one millivolt to 50 volts/division (at a reduced bandwidth of 50 kilohertz), and Channel 2 the vertical (Y) deflection. The resultant CRT display is presented on a 6 X 10 division graticule (each division equals 0.203 inch). The 212 is operated either from AC line voltage or from internal rechargeable batteries. The internal batteries are recharged from the AC power line by the integral battery charger. This instrument will meet the following electrical characteristics after complete instrument calibration. These characteristics apply over an ambient temperature of -15àC to +55àC (+5àF to +131àF), except as otherwise indicated. Warmup time for given accuracies is five minutes. VERTICAL DEFLECTION SYSTEM DEFLECTION FACTOR: Calibrated Range: One millivolt to 50 volt/division. 15 steps in 1-2-5 sequence. Accuracy: Within 5% with VOLTS/DIV VAR control in CAL position and gain correctly set at 5 mV/div. Uncalibrated (variable) Range: Continuously variable between calibrated settings. Extends maximum deflection factor to at least 125 volts/division. BANDWIDTH (with six-division reference): 10 mV/DIV to 50 V/DIV: DC to at least 500 kilohertz. 5 mV/DIV: DC to at least 400 kilohertz. 2 mV/DIV: DC to at least 200 kilohertz. 1 mV/DIV: DC to at least 100 kilohertz. Lower Bandwidth Limit, AC (capacitively) Coupled: about 2 hertz at all deflection factors. INPUT RESISTANCE: Approximately one megohm. INPUT CAPACITANCE: 1 mV/DIV to 50 mV/DIV: picofarads. 100 mV/DIV to 50 V/DIV: picofarads.
Approximately 160 Approximately 140
MAXIMUM USABLE INPUT VOLTAGE: 50 V/DIV to .1 V/DIV: 600 volts (DC + peak AC). 600 volts peak-to-peak AC (five megahertz or less). 50 mV/DIV to 1 mV/DIV: 600 volts (DC + peak AC). AC not over 2 kilohertz or risetime not less than 100 nanoseconds. CHOPPED MODE: From 500 ms/DIV to 2 ms/DIV of time base at approximately 50 kilohertz. ALTERNATE MODE: From 1 ms/DIV to 5ps/DIV of time base. INPUT IMPEDANCE MATCHING: Matched to within approximately 10%.
1-1
TM 9-6625-646-14&P GAIN ACCURACY BETWEEN CHANNELS: Within 5% with both VOLTS/DIV VAR controls in CAL position and gain correctly set at 5 mV/DIV. TRIGGERING TRIGGER SENSITIVITY: Internal: COMP: 0.2 division from DC to 500 kilohertz. CH 2: 0.2 division from 2 hertz to 500 kilohertz. External: 1.0 volt from DC to 500 kilohertz. PRESET TRIGGER LEVEL: Triggered at preset level on positive slope of triggering signal. Sensitivity same as stated above. DISPLAY JITTER: 0.5 microsecond or less at 500 kilohertz. EXTERNAL TRIGGER: Input Resistance: Approximately one megohm. Input Capacitance: Approximately 30 picofarads. Maximum Usable Input Voltage: 8 volts (DC + peak AC) 16 volts peak-to-peak AC (one megahertz or less). HORIZONTAL DEFLECTION SYSTEM SWEEP RATE: Calibrated Range: 500 milliseconds to five microseconds/ division. 16 steps in 1-2-5 sequence. Accuracy (over center eight divisions): Within 5% with HORIZ MAG control in CAL position and timing correctly set at 1 ms/DIV (disregard first 0.5 microsecond of total sweep length). Linearity (any two division portion within center eight divisions): Within 5% (disregard first 10% of total sweep length). Variable Magnifier: Continuously variable between Calibrated Deflection Factor: 1 millivolt to 50 volts/ division. Variable: At least five times (using HORIZ MAG). Accuracy: Within 10% (with HORIZ MAG control in CAL position). X-Y Phasing: Less than 3à at five kilohertz. Maximum Input Voltage: 600 volts (DC + peak AC); 600 volts (peak-to-peak AC). DISPLAY GRATICULE: Type: Internal black line, non-illuminated. Area: Six divisions vertical by 10 divisions horizontal. Each division equals 0.203 inch. PHOSPHOR: P31 Standard. ISOLATION PROBE COMMON TO 212 CASE EXTERIOR: (When battery operated with AC power plug secured in the insulated cover.) Maximum safe potential between probe common (floating circuit ground) and 212 case exterior not to exceed 500 V RMS sinusoidal, or 700 V (DC + peak AC). PROBE COMMON TO AC LINE: Maximum safe potential between probe common (floating circuit ground) and the AC power line is not to exceed 250 V RMS sinusoidal minus the AC power line RMS voltage. (i.e., when the AC power line RMS voltage is 117 V, the maximum allowable potential on the probe common is 250 -117 = 133 V RMS.) calibrated settings. Extends maximum sweep rate to at least 1.0 microsecond/division. CH 1 HORIZONTAL INPUT:
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TM 9-6625-646-14&P AC OPERATION CAUTION Due to the capacitive line input circuit, sudden voltage changes may cause damaging input current transients. Avoid operating this instrument from squarewave inverter supplies, or other sources that produce large voltage transients. LINE VOLTAGE RANGE: 110 to 126 volts, AC. Batteries can not be charged during AC operation. Instrument can be operated between 104 and 110 volts with resulting slow discharge of internal batteries. LINE FREQUENCY: 58 to 62 hertz. NOTE Refer to Option and Corrective Maintenance information for other line voltages and frequencies. MAXIMUM POWER CONSUMPTION: Three watts or less at 126 volts, 60 hertz. INTERNAL BATTERY OPERATION BATTERIES: 10 rechargeable A nickel-cadmium cells. CHARGE TIME (from AC line): 16 hours for full charge (instrument off during charge cycle). POWER (BATTERY) INDICATOR: When extinguished, indicates less than 10 minutes of scope operating life left in the batteries. BATTERY EXCESSIVE DISCHARGE PROTECTION: Instrument operation automatically interrupted when battery charge drops to 10 volts +0.5 volt. TYPICAL OPERATING TIME (at maximum trace intensity after full charge cycle at +20àC to +30àC): Three to five hours. Longest operating time provided at lower trace intensity. TYPICAL CHARGE CAPACITY (reference to charge/ discharge at +20àC to +30àC):
CHARGE TEMPERATURE 0°C (+32°F) +20àC to +30àC (+68° F to +86à F) 40°C (+104àF)
OPERATING TEMPERATURE 15°C +20°C to +30°C +55°C (+5°F) (+68°F to +860F) (+131°F) 40% 60% 50% 65% 100% 85% 40% 65% 55%
GENERAL ENVIRONMENT: Temperature: Operating from Batteries, -15°C to +55àC (+5àF to +131àF). Charging or operating from AC line, 0°C to +40°C (+32°F to +104àF). Storage, -40àC to +60°C (-40àF to +140à F). Altitude: Operating, to 25, 000 feet (maximum operating temperature decreased by 10C per 1, 000 feet above 15, 000 feet). Non-operating, to 50, 000 feet. Humidity (operating and non-operating): 5 cycles (120 hours) to 95% relative humidity referenced to MIL-E-16400F. Shock (operating and non-operating): Tested with two shocks at 150 g, one-half sine, two millisecond duration each direction along three major axes. WEIGHT (without accessories): 3.4 pounds (1.5 kilograms) DIMENSIONS (measured at maximum points): Height: 3.0 inches (7.6 centimeters). Width: 5.25 inches (13.2 centimeters). Depth: 8.9 inches (22.6 centimeters).
1-3
TM 9-6625-646-14&P OPTION INFORMATION Your instrument may be equipped with one or more options. This section describes those options or directs the reader to where the option is documented. OPTION 1 Option 1 equips the 212 for operation from a 220 to 250 V ac 48 to 52 Hz power line source. Option 1 parts values that differ from the standard 212 are listed here. A power cord cable assembly, for adapting to appropriate power plugs, is included with Option 1 instruments. Refer to the Corrective Maintenance and Diagrams sections of this manual for additional information concerning Option 1. ELECTRICAL PARTS LIST DIFFERENCES FOR OPTION 1 A3 C204 C210 C212 C215 670-2405-21* 283-0279-00 285-0932-00 285-0933-00 283-0279-00 POWER SUPPLY Circuit Board Assembly (Option 1) 0.001 UF, 20%, 3 KV 1.0 UF, 10%, 400V 2.0 UF, 10%, 400V 0.001 UF, 20%, 3 KV
ADDITIONAL STANDARD ACCESSORIES FOR OPTION 1 161-0077-01 CABLE ASSEMBLY, POWER (Adapts to users plug type)
*In some Option 1 instruments, the suffix number on the board may not be marked -21. OPTION 2 Option 2 equips the 212 for operation from a 90 to 110 V ac 48 to 52 Hz power line source. Option 2 parts values that differ from the standard 212 are listed here. Refer to the Corrective Maintenance and Diagrams sections of this manual for additional information concerning Option 2. ELECTRICAL PARTS LIST DIFFERENCES FOR OPTION 2 A3 C210 C212 670-2405-31 ** 285-0934-00 285-0935-00 POWER SUPPLY Circuit Board Assembly (Option 2) 2.2 UF, 10%, 200V 4.4 UF, 10%, 200V
**ln some Option 2 instruments, the suffix number on the board may not be marked -31.
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TM 9-6625-646-14&P
Fig. &
Index No. -1 -2 -3 -4 Tektronik Part No. 015-0199-01 016-0512-00 346-0104-00 159-0121-00 070-1375-00 070-1376-00 Serial/Model No. Eff Dscont 1 1 1 2 1 1 Qty 1 2 3 4 5 Name & Description Mfr Code 80009 80009 17516 75915 80009 80009 Mfr Part Number 016-0199-01 016-0512-00 4188-BA 212.400 070-1375-00 070-1376-00
VISOR, CRT: CASE, CARRYING: STRAP, CARRYING: FUSE, CARTRIDGE :DIN, 0.4A, 250V,5 SEC MANUAL, TECH: OPERATORS MANUAL, TECH: INSTRUCTION
Figure 1-2. 212 Oscilloscope Accessories
1-5
TM 9-6625-646-14&P MANUAL CHANGE INFORMATION At 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 and shipping requirements, we can't get these changes immediately into printed manuals. Hence, your manual may contain new change information on following pages. A single change may affect several sections. Since the change information sheets are carried in the manual until all changes are permanently entered, some duplication may occur. If no such change pages appear following this page, your manual is correct as printed.
SERVICE NOTE Because of the universal parts procurement problem, some electrical parts in your instrument may be different from those described in the Replaceable Electrical Parts List. The parts used will in no way alter or compromise the performance or reliability of this instrument. They are installed when necessary to ensure prompt delivery to the customer. Order replacement parts from the Replaceable Electrical Parts List.
1-6
TM 9-6625-646-14&P CALIBRATION TEST EQUIPMENT REPLACEMENT Calibration Test Equipment Chart This chart compares TM 500 product performance to that of older Tektronix equipment. Only those characteristics where significant specification differences occur, are listed. In some cases the new instrument may not be a total functional replacement. Additional support instrumentation may be needed or a change in calibration procedure may be necessary. Comparison of Main Characteristics
DM 501 replaces 7D13 PG 501 replaces 107 108 111 114 115 PG 501 - Risetime less than 3.5 ns into 50. PG 501 - 5 V output pulse; 3.5 ns Risetime. PG 501 - Risetime less than 3.5 ns; 8 ns Pretrigger pulse delay. PG 501 + 5 V output. PG 501 - Does not have Paired, Burst, Gated, or Delayed pulse mode; +5 V dc Offset. Has +5 V output. PG 502 - 5 V output PG 502 - Risetime less than 1 ns; 10 ns Pretrigger pulse delay. PG 502 -+5 V output PG 502 - Does not have Paired, Burst, Gated, Delayed & Undelayed pulse mode; Has ±5 V output. PG 502 - Does not have Paired or Delayed pulse. Has ±5 V output. PG 506 - Positive-going trigger output signal at least 1 V; High Amplitude output, 60 V. PG 506 - Does not have chopped feature. 107 108 111 114 115 - Risetime less than 3.0 ns into 50. - 10 V output pulse; 1 ns Risetime. - Risetime 0.5 ns; 30 to 250 ns Pretrigger Pulse delay. - ±10 V output. Short proof output. - Paired, Burst, Gated, and Delayed pulse mode; +10 V output. Short-proof output. - 10 V output. - Risetime 0.5 ns; 30 to 250 ns Pretrigger pulse delay. - 10 V output. Short proof output. - Paired, Burst, Gated, Delayed & Undelayed pulse mode; +10 V output. Short-proof output. - Paired and Delayed pulse; 10 V output. - Positive and Negative-going trigger output signal, 50 ns and 1 V; High Amplitude output, 100 V. - Comparator output can be alternately chopped to a reference voltage. - Amplitude range 40 mV to 10 V p-p. - Frequency range 350 kHz to 100 MHz. - Frequency range 65 MHz to 500 MHz. - Marker outputs, 5 sec to 1 us. Sinewave available at 20, 10, and 2 ns. Trigger pulses 1, 10, 100 Hz; 1, 10, and 100 kHz. Multiple time-marks can be generated simultaneously. - Marker outputs, 1, 10, 100, 1000, and 10, 000 us, plus 10 ns sinewave. - Marker outputs, 5 sec to 2 ns. Sinewave available at 50, 20, 10, 5, and 2 ns. Separate trigger pulses of 1 and .1 sec; 10, 1, and .1 ms; 10 and 1 /s. Marker amplifier provides positive or negative time marks of 25 V min. Marker intervals of 1 and .1 sec; 10, 1, and .1 ms; 10 and 1 us. - Marker outputs, 5 sec to 0.1 us. Sinewave available to 50, 10, and 5 ns. Separate trigger pulses, from 5 sec to 0.1 us. Multiple time-marks can be generated simultaneously.
PG 502 replaces
107 108 111 114 115
108 111 114 115
2101 PG 506 replaces 106
2101 106
067-0502-01
0502-01
SG 503 replaces 190, 190A, 190B 191 067-0532-01 TG 501 replaces 180, 180A
SG 503 - Amplitude range 5 mV to 5.5 V p-p. SG 503 - Frequency range 250 kHz to 250 MHz. SG 503 - Frequency range 250 kHz to 250 MHz.
190B 191 0532-01
181 184
TG 501 - Marker outputs, 5 sec to 1 ns. Sinewave available at 5, 2, and 1 ns. Trigger output - slaved to marker output from 5 sec through 100 ns. One time-mark can be generated at a time. TG 501 - Marker outputs, 5 sec to 1 ns. Sinewave available at 5, 2, and 1 ns. TG 501 - Marker outputs, 5 sec to 1 ns. Sinewave available at 5, 2, and 1 ns. Trigger output - slaved to marker output from 5 sec through 100 ns. One time-mark can be generated at a time.
180A
181 184
2901
TG 501 - Marker outputs, 5 sec to 1 ns. Sinewave available at 5, 2, and 1 ns. Trigger output - slaved to marker output from 5 sec through 100 ns One time-mark can be generated at a time.
2901
NOTE: All TM 500 generator outputs are short-proof. All TM 500 plug-in instruments require TM 500-Series Power Module. 1-7
TM 9-6625-646-14&P
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TM 9-6625-646-14&P SECTION 2 FUNCTIONS OF CONTROLS AND CONNECTORS The controls and connectors necessary for operation of the 212 are located on the right side of the instrument. (See Fig. 2-1.) The POWER (BATTERY) indicator is on the front panel. A brief description of each control and connector is given here. VOLTS/DIV-selects vertical deflection factor (vertical VARiable control must be in CAL position for indicated deflection. INPUT COUPLING-selects the method used to couple the channel input signal to the vertical amplifier system. AC-the DC component of input signal is blocked. GND-vertical amplifier input circuit is grounded. The applied input signal is connected to ground through a one megohm resistor to provide a precharge path for the AC input coupling capacitor. DC-all components of the input signal are passed to the vertical amplifier system input. STEP ATTEN BALance-a screwdriver adjustment to balance the vertical amplifier system for minimum trace shift when switching deflection factors. Vertical POSition-controls the vertical position of the appropriate trace. OFF detent turns the channel off. VOLTS/DIV VARiable-provides a continuously variable deflection factor between the calibrated settings of the VOLTS/DIV switch for the appropriate vertical channel. VERTical GAIN-screwdriver adjustment to set the gain of the vertical amplifier system. AUTO PRESET-screwdriver adjustment to set the AUTO PRESET trigger point for automatic trigger operation. Trigger SOURCE-selects the source of the trigger signal. COMP-the sweep is triggered from a sample of the vertical deflection signal after the vertical switching. CH 2-the sweep is triggered from a sample of the vertical deflection signal before the vertical switching and only from CH 2. EXT-the sweep is triggered from the signal applied to the EXT TRIG banana jack.
Figure 2-1. Side Panel controls and connectors.
2-1
TM 9-6625-646-14&P LEVEL/SLOPE-selects the amplitude point and the slope of the trigger signal on which the sweep is triggered. When the indicator dot is to the left of center, the sweep is triggered on the positive-going slope of the trigger signal; to the right of center, on the negativegoing slope. When the LEVEL/SLOPE control is set to the AUTO PRESET detent, the sweep is automatically triggered at a preset level on the positive-going slope. INTENSITY-controls brightness of CRT display. SWP CAL-screwdriver adjustment to provide calibrated sweep timing. POWER-controls power to the instrument. Does not interrupt charging current to the internal batteries when the instrument is connected to an AC line voltage. FOCUS-screwdriver adjustment to obtain a well-defined display. HORIZontal MAGnifier-provides continuously variable sweep magnification to a maximum of approximately five times the sweep rate indicated by the SEC/DIV switch. HORIZontal GAIN-screwdriver adjustment to set the basic gain of the horizontal amplifier system.
Horizontal POSition-controls the horizontal position of the trace. SEC/DIV-selects horizontal sweep rate (HORIZ MAG must be in CAL position for indicated sweep rate) X-Y position allows for X-Y operation; CH 2 supplies the vertical deflection and CH 1 the horizontal deflection. EXT TRIG-banana jack for input of an external trigger signal. COMMON-banana jack to establish common ground between the 212 and the external signal source or equipment under test. WARNING COMMON and probe ground straps are electrically connected. Therefore, an elevated reference applied to any is present on each - as indicated by the yellow warning bands under the probe retractable hook tips. POWER (BATTERY) Indicator-red light to indicate when the instrument is on. When light extinguishes, less than 10 minutes of operating life remain.
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TM 9-6625-646-14&P SECTION 3 PREVENTIVE MAINTENANCE Preventive maintenance, when performed on a regular basis, can prevent instrument breakdown and may improve the reliability of this instrument. The severity of environment to which the 212 is subjected will determine the frequency of maintenance. A convenient time to perform preventive maintenance is preceding recalibration of the instrument.
Disassembly To gain access to the interior of the instrument, unwind both the probe cords and the power cord from the rear of the instrument. Remove the five screws in the bottom cover of the instrument. See Fig. 3-1. Gently separate the bottom cover from the instrument and lay aside. The Power Supply circuit board with the batteries can be lifted up and pivoted out of the way. Most of the internal workings of the instrument are now accessible. If it is necessary to have access to the front of the Input circuit board, remove the knobs from all of the external control shafts. Remove the four screws securing the side panel to the Input circuit board and remove the instrument side panel.
Cleaning The 212 should be cleaned as often as operating conditions require. Accumulation of dirt in the instrument can cause component breakdown. The high impact plastic covers provide protection against dust in the interior of the instrument. Loose dust accumulated on these covers can be removed with a soft cloth or small brush. The brush is also useful for dislodging dirt on and around the side-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. It should be only occasionally necessary to clean the interior. The best way to clean the interior is to blow off the accumulated dust with dry, low-velocity air. A softbristle brush or a cotton-tipped applicator is useful for cleaning in narrow spaces or for cleaning more delicate circuit components.
Figure 3-1. Location of screws securing bottom cover and side panel.
CAUTION Avoid the use of chemical cleaning agents which might damage the plastics used in this instrument. Avoid chemicals which contain hydrochloric acid, sodium hydroxide, or sulfuric acid. Visual Inspection The 212 should be inspected occasionally for such defects as broken connections, improperly seated transistors, damaged circuit boards, and heat-damaged parts.
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TM 9-6625-646-14&P parts. The corrective procedure for most visible defects is apparent; however, particular care must be taken if heat-damaged components are found. Overheating usually indicates other trouble in the instrument; therefore, it is important that the cause of the overheating be corrected to prevent recurrence of the damage. Semiconductor Checks Periodically checking the semiconductors in the 212 is not recommended. The best check of semiconductor performance is actual operation in the instrument. If it is desired to check the performance of a semiconductor out of the instrument, a dynamic checker such as a TEKTRONIX Type 576 Transistor Curve Tracer is recommended. Lead configurations of the semiconductors used in the 212 are shown in Fig. 5-2. An extracting tool should be used to remove the 14-, and 16-pin flat integrated circuits to prevent damage to the pins. If an extracting tool is not available when removing one of these integrated circuits, pull slowly and evenly on both ends of the device. Try to avoid having one end of the integrated circuit disengage from the socket before the other, as the pins may be damaged. When replacing semiconductors, key the semiconductor's index with that of its socket. Failure to do so can result in damaged components. Recalibration To assure accurate measurements, check the calibration of this instrument after each 1000 hours of operation or every six months if used infrequently. In addition, replacement of components may necessitate recalibration of the affected circuits. The calibration procedure can also be helpful in localizing certain troubles in the instrument. In some cases, minor troubles may be revealed or corrected by recalibration.
Figure 3-2. Location of circuit boards within the 212.
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TM 9-6625-646-14&P SECTION 4 CALIBRATION General To assure instrument accuracy, check the calibration of the 212 every 1000 hours of operation, or every six months if used infrequently. Before complete calibration, throughly clean and inspect this instrument as outlined in the Preventive Maintenance section. Tektronix, Inc., provides complete instrument repair and recalibration at local Field Service Centers and the Factory Service Center. Contact your local TEKTRONIX Field Office or representative for further information. To aid in locating a step in this procedure, an index is given prior to the complete procedure. Completion of each step in the Calibration procedure ensures that this instrument meets the electrical specifications given in the Introduction of this manual. Where possible, instrument performance is checked before an adjustment is made. For best overall instrument performance, make each adjustment to the exact setting even if the CHECK- step is within the allowable tolerances. TEST EQUIPMENT REQUIRED The following test equipment and accessories, or their equivalent, are required for complete calibration of the 212. Given specifications for the test equipment are the minimum necessary for accurate calibration. Therefore, the specifications of any test equipment must either meet or exceed those listed below. All test equipment is assumed to be correctly calibrated and operating within the listed specifications. Detailed operating instructions for the test units are not given in this procedure. Refer to the instruction manual for the test equipment if more information is needed.
Special Calibration Fixtures Special TEKTRONIX Calibration fixtures are used in this procedure only where they facilitate instrument calibration. These special calibration fixtures are available from Tektronix, Inc. Order by part number through your local TEKTRONIX Field Office or representative.
Description
1. Time-Mark Generator
TABLE 4-1. TEST EQUIPMENT Minimum Specifications
Marker outputs, 5 microseconds to 0.1 second; marker accuracy, within 0.1%.
Usage
Example
a. TEKTRONIX 2901 Time-Mark Generator. b. TEKTRONIX 184 Time-Mark Generator. a. TEKTRONIX calibration fixture Part Number 067-0502-01. a. TEKTRONIX Type 106 Square-Wave Generator. a. General Radio 1310-B Oscillator. operation checks. a. Triplett Model 630-NA. b. Simpson Model 262.
Horizontal timing check and adjustment.
2. Standard Amplitude Calibrator
3. Square-Wave Generator 4. Low-Frequency Constant-Amplitude Signal Generator 5. DC Voltmeter
Amplitude accuracy, 0.25%; signal amplitude, 5 millivolts to 100 volts; output signal one-kilohertz square wave. Frequency, one kilohertz; risetime, 100 nanoseconds or less; output amplitude, 0.4 volt to 40 volts. Frequency, one kilohertz to 500 kilohertz; output amplitude, at least 200 millivolts. Range, zero to 1000 volts; accuracy, within 3%; input impedance, 20, 000/volt.
Vertical and horizontal amplifier gain checks and adjustments. Vertical amplifier compensation checks and adjustments. Vertical Amplifier bandwidth check. Trigger Power supply output level checks. Vertical and horizontal centering adjustment. CRT grid bias adjustment.
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TM 9-6625-646-14&P
Description
6. Cable 7. Adapter 8. Adapter 9. Termination 10. Attenuator 11. Adapter 12. T-Connector 13. Screwdriver 14. Low-Capacitance Screwdriver
TABLE 4-1 (cont) Minimum Specifications
Impedance, 50 ohms; type, RG-58/U; length, 42 inches; connectors, BNC. Connectors, BNC female and dual banana plug. Connectors, GR874 and BNC female. Impedance, 50 ohms; accuracy, 2%; connectors, BNC. Ratio, 10X; connectors, BNC; impedance, 50 ohms. Connectors, probe tip to BNC. Connectors, BNC. Three-inch shaft, 3/32 inch bit. 1 1/2-inch shaft.
Usage
Example
a. TEKTRONIX Part Number 012-0057-01. a. TEKTRONIX Part Number 103-0090-00. a. TEKTRONIX Part Number 017-0063-00. a. TEKTRONIX Part Number 011-0049-01. a. TEKTRONIX Part Number 011-0059-01. a. TEKTRONIX Part Number 013-0084-01. a. TEKTRONIX Part Number 103-0030-00. a. Xcelite R-3323. a. TEKTRONIX Part Number 003-0000-00.
External trigger operation check. Horizontal gain check and adjustment. External trigger checks. Vertical Amplifier compensation checks and adjustment. Vertical amplifier compensation checks and adjustment. Vertical amplifier bandwidth check. Used throughout procedure for signal interconnection. External trigger operation checks. Used throughout Procedure to adjust variable resistors. Used to adjust variable capacitors.
INDEX TO CALIBRATION PROCEDURE Power Supply and Display 1. Check Power Supply DC Levels 2. Adjust CRT Grid Bias (internal adjustment of R273) 3. Adjust FOCUS (external side panel adjustment of R398) 4. Adjust Trace Rotation (internal adjustment of R141)
side panel adjustment of R415) 7. Adjust CH 2 STEP ATTENuation BALance (external side panel adjustment of R315) 8. Adjust VERTical GAIN (external side panel adjustment of R470) 9. Check CH 2 VARiable VOLTS/DIV Range 10. Check CH 2 VOLTS/DIV Accuracy VOLTS/DIV Range 11. Check CH 1 VOLTS/DIV Accuracy and VARiable 12. Adjust CH 1 VOLTS/DIV Switch Compensation (internal side panel adjustment of C407, C408, C409)
Vertical System Adjustment 5. Adjust Vertical adjustment of R101) DC Centering (internal
13. Adjust CH 2 VOLTS/DIV Switch Compensation (internal side panel adjustment of C307, C308, C309 14. Check CH 2 Vertical Amplifier Bandwidth
6. Adjust CH 1 STEP ATTENuation BALance (external
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TM 9-6625-646-14&P 15. Check CH 1 Vertical Amplifier Bandwidth Trigger Circuit Adjustment 16. Adjust AUTO PRESET (external side panel adjustment of R375) 17. Check Trigger Circuit Operation Horizontal System Adjustment 18. Adjust Horizontal Centering (internal adjustment of R366) 19. Adjust HORIZontal GAIN (external side panel adjustment of R475) 20. Adjust SWEEP CALibration (external side panel adjustment of R370) 21. Check HORIZ MAG Range 22. Check SEC/DIV Accuracy PRELIMINARY PROCEDURE This instrument should be adjusted at an ambient temperature of +250C (+ 50C) for best overall accuracy. 1. Remove the instrument covers as described in the Disassembly Instructions in the Preventive Maintenance section. 2. Connect the instrument to a 117 VAC 60 Hz line source. If the batteries are not fully charged, leave the 212 connected to the line with the power switch turned off for a period of approximately one hour before continuing with calibration. 3. Set the instrument controls as given under Preliminary Control Settings. Allow at least five minutes of warmup before proceeding. NOTE Titles for external controls of this instrument are fully capitalized in this procedure (e.g., INTEASITY). Internal adjustments are initial capitalized only (e.g., Grid Bias). PRELIMINARY CONTROL SETTINGS Preset the instrument controls to the settings given below when starting a calibration procedure. Channel 1 Controls VOLTS/DIV VOLTS/DIV VAR POS INPUT COUPLING 5m CAL Midrange GND
Channel 2 Controls VOLTS/DIV VOLTS/DIV VAR POS INPUT COUPLING 5m CAL OFF GND
Trigger Controls SOURCE LEVEL/SOURCE COMP AUTO PRESET
Sweep Controls SEC/DIV HORIZ MAG POS 1m CAL Midrange Display Controls POWER INTENSITY ON Fully Counterclockwise
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TM 9-6625-646-14&P CALIBRATION PROCEDURE POWER SUPPLY and DISPLAY Equipment Required 1. DC Voltmeter Control Setting Preset instrument controls to the settings given under Preliminary Control Settings. 1. Check Power Supply DC Levels NOTE If the instrument has been operating satisfactorily prior to recalibration, proceed with step 2. a. Using the DC voltmeter, measure the DC level of the power supplies given in Table 4-2. Observe proper meter polarity. See Fig. 4-1 for test point locations. 2. Three-inch Screwdriver 2 of plug P3 (negative meter lead to pin 2) on the Power Supply Board. See Fig. 4-1. b. Turn the INTENSITY control fully clockwise. c. CHECK-Meter reading of +1.9 volts. d. ADJUST-CRT Grid Bias, R273 (see Fig. 4-1) for a meter reading of +1.9 volts. e. Disconnect all test equipment. Turn the INTENSITY control fully counterclockwise. 3. Adjust FOCUS a. Turn CH 2 POS midrange and CH 1 POS to the OFF detent. b. Set the SEC/DIV switch to X-Y and adjust the INTENSITY control for a nominal display intensity. c. ADJUST-FOCUS, R398 (located on the 212 side panel) for a well-defined dot. 4. Adjust Trace Rotation a. Set the SEC/DIV switch to 1 m. b. CHECK-Free-running sweep is parallel with a horizontal graticule line. c. ADJUST-Trace Rotation, R141 (see Fig. 4-2) so the trace is parallel with the center horizontal graticule line.
Supply -5.6 volt +5.6 volt +65 volt -1000 volt
TABLE 4-2. Power Supply Accuracy Measurement -5.6 volts ±0.4 volt +5.6 volts ±0.4 volt +65 volts ±4 volts -960 volts ±40 volts (due to meter loading)
2. Adjust CRT Grid Bias a. Connect the DC voltmeter between pin 5 and pin
Figure 4-1. Location of power supply test points and CRT Grid Bias adjustment.
Figure 4-2. Location of Trace Rotation adjustment.
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TM 9-6625-646-14&P VERTICAL SYSTEM ADJUSTMENT Equipment Requested 1. Standard Amplitude Calibrator 2. Square-Wave Generator 3. Low Frequency Constant Amplitude Signal Generator 4. DC Voltmeter 5. GR-to-BNC Female Adapter Control Settings Preset instrument controls to the settings given under Preliminary Control Settings, except as follows: INTENSITY INPUT COUPLING (both) Visible Display DC 6. 7. 8. 9. 10. Probe Tip-to-BNC Adapter 50-Ohm BNC Termination 10X 50-Ohm Attenuator Three-inch Screwdriver Low-Capacitance Screwdriver
6. Adjust CH 1 STEP ATTENuator BALance a. Rotate the CH 1 VOLTS/D)V switch from 50 m to 1 m. b. CHECK-The CRT display for 0.1 division or less of trace shift between adjacent switch positions when rotating the VOLTS/DIV switch from 50 m to 1 m. c. ADJUST-CH 1 STEP ATTEN BAL, R415 (located on the side panel) for minimum trace shift when rotating the CH 1 VOLTS/DIV switch from 50 m to 1 m. 7. Adjust CH 2 STEP ATTENuator BALance a. Turn the CH 1 POS control to the OFF detent and the CH 2 POS control to midrange. b. Rotate the CH 2 VOLTS/DIV switch from 50 m to 1 m. c. CHECK-The CRT display for 0.1 division or less of trace shift between adjacent switch positions when rotating the VOLTS/DIV switch from 50 m to 1 m. d. ADJUST-CH 2 STEP ATTEN BAL, R315 (located on the side panel) for minimum trace shift rotating the CH 2 VOLTS/DIV switch from 50 m to 1 m. 8. Adjust VERTical GAIN a. Set the CH 2 VOLTS/DIV switch to 5 m. b. Connect the CH 2 probe tip to the output of the Standard Amplitude Calibrator via a probe tip-to-BNC adapter. c. Set the Standard Amplitude Calibrator for a 20 millivolts output signal. d. CHECK-The CRT display for four divisions of deflection within 0.2 division. e. ADJUST-VERT GAIN, R470 (located on the side panel) for exactly four divisions of deflection.
5. Adjust Vertical DC Centering a. Connect the DC voltmeter between pin 11 of U105 (positive meter lead to pin 11) and ground (see Fig. 4-3). b. Adjust CH 1 Vertical POS control for a 0 volt meter reading. c. CHECK-Trace should be within approximately 0.4 division of graticule center. d. ADJUST-Vertical Centering, R101 (see Fig. 4-3) to position the trace to the center horizontal graticule line. e. Disconnect all test equipment.
Figure 4-3. Location of Vertical Centering adjustment and test point.
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TM 9-6625-646-14&P 9. Check CH 2 VARiable VOLTS/DIV Range a. Rotate the CH 2 VOLTS/DIV VAR control fully clockwise. b. CHECK-The CRT display for 1.6 divisions or less of deflection. 1.6 divisions of deflection indicates a VARiable VOLTS/DIV range of at least 2.5: 1. c. Set the VARiable VOLTS/D IV control to CAL. 10. Check CH 2 VOLTS/DIV Accuracy a. CHECK-Using the CH 2 VOLTS/DIV switch and Standard Amplitude Calibrator settings given in Table 43, check that the deflection factor accuracy for CH 2 is within 5% at each position. a. Turn CH 2 POS to the OFF detent and the CH 1 POS to midrange. b. Connect the CH 1 probe tip to the output of the Standard Amplitude Calibrator via a probe tip-to-BNC adapter. c. CHECK-Using the CH 1 VOLTS/DIV switch and Standard Amplitude Calibrator settings given in Table 43, that the deflection factor accuracy of CH 1 at each position is within 5%. d. Set the Standard Amplitude Calibrator for a 20 millivolts output signal. e. Set the CH 1 VOLTS/DIV switch to 5 m. f. Rotate the CH 1 VARiable VOLTS/DIV control fully clockwise. g. CHECK-The CRT display for 1.6 divisions or less of deflection. 1.6 divisions of deflection indicates a VARiable VOLTS/DIV range of at least 2.5: 1. h. Set the VARiable VOLTS/DIV control to CAL. 12. Adjust CH 1 VOLTS/DIV Switch Compen-sation a. Set the CH 1 VOLTS/DIV switch to 0.1 V. b. Connect the CH 1 probe tip to the high amplitude output of the Type 106 Square-Wave generator via a GR-to-BNC female adapter, a 50-ohm BNC termination, and a probe tip-to-BNC adapter. c. Adjust the Square-Wave generator for a fourdivision display of a one kilohertz square wave. d. Adjust the Triggering controls for a stable display. e. CHECK-The CRT display for flat-top waveform with no more than +0.2 division, -0.1 division, or a total of 0.2 division of aberration. NOTE If C307, C308, C309, C407, C408, or C409 require adjustment, it will be necessary to remove the instrument side panel from the Input Board. Refer to the Disassembly Instructions for removal procedure.
TABLE 4-3. Vertical Deflection Accuracy VOLTS/DIV Standard Vertical Maximum Switch Amplitude Deflection Error For Setting Calibrator in Ù5% Accuracy Output Divisions 1m 5 millivolts 5 Ù0.25 division Ù0.25 division 2m 10 millivolts 5
5m 10 m 20 m 50 m .1 .2 .5 1 2 5 10 20 50 20 millivolts 50 millivolts 0.1 volt 0.2 volt 0.5 volt 1 volt 2 volts 5 volts 10 volts 20 volts 50 volts 100 volts 100 volts 4 5 5 4 5 5 4 5 5 4 5 5 2 Previously set in step 8. Ù0.25 division Ù0.25 division Ù0.2 division Ù0.25 division Ù0.25 division Ù0.2 division Ù0.25 division Ù0.25 division Ù0.2 division Ù0.25 division Ù0.25 division Ù0.1 division
b. Disconnect the CH 2 probe tip from the Standard Amplitude Calibrator. 11. Check CH 1 VOLTS/DIV Accuracy and VARiable VOLTS/DIV Range
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TM 9-6625-646-14&P f. ADJUST-C407 (see Fig. 4-4) for no more than +0.2 division, -0.1 division, or a total of 0.2 division of aberration. (Use a low-capacitance screwdriver.) g. Set the CH 1 VOLTS/DIV switch to 1 and adjust the Square-Wave generator for a four-division display. h. CHECK-The CRT display for flat-top waveform with no more than +0.2 division, -0.1 division, or a total of 0.2 division of aberration. i. ADJUST-C408 (see Fig. 4-4) for no more than +0.2 division, -0.1 division, or a total of 0.2 division of aberration. j. Set the VOLTS/DIV switch to 10, remove the 50ohm BNC termination from the test setup, and adjust the Square-Wave generator for a four-division display. k. CHECK-The CRT display for a flat-top waveform with no more than +0.2 division, -0.1 division, or a total of 0.2 division of aberration. I. ADJUST-C409 (see Fig. 4-4) for no more than +0.2 division, -0.1 division, or a total of 0.2 division of aberration. m. Disconnect CH 1 probe tip from the test setup.
13. Adjust CH 2 VOLTS/DIV Switch Compensation a. Turn CH 1 POS control to the OFF detent and turn CH 2 POS control to midrange. b. Set the CH 2 VOLTS/DIV switch to 0.1 V/div. c. Connect the CH 2 probe tip to the high amplitude output of the Type 106 Square-Wave generator via a GR-to-BNC female adapter, a 50-ohm BNC termination, and a probe tip-to-BNC adapter. d. Adjust the Square-Wave generator for a fourdivision display of a one-kilohertz square wave. e. CHECK-The CRT display for flat-top waveform with no more than +0.2 division, -0.1 division, or a total of 0.2 division of aberration. f. ADJUST-C307 (see Fig. 4-4) for no more than +0.2 division, -0.1 division, or a total of 0.2 division of aberration. g. Set the CH 2 VOLTS/DIV switch to 1 and adjust the Square-Wave generator for a four-division display. h. CHECK-The CRT display for a flat-top waveform with no more than +0.2 division, -0.1 division, or a total of 0.2 division of aberration. i. ADJUST-C308 (see Fig. 4-4) for no more than +0.2 division, -0.1 division, or a total of 0.2 division of aberration. j. Set the CH 2 VOLTS/DIV switch to 10, remove the 50-ohm BNC termination from the test setup, and adjust the Square-Wave generator for a four-division display. k. CHECK-The CRT display for a flat-top waveform with no more than +0.2 division, -0.1 division, or a total of 0.2 division of aberration. I. ADJUST-C309 (see Fig. 4-4) for no more than +0.2 division, -0.1 division, or a total of 0.2 division of aberration. m. Disconnect all test equipment, and re-install the instrument side panel.
Figure 4-4. Location of attenuator compensation capacitors.
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TM 9-6625-646-14&P 14. Check CH 2 Vertical Amplifier Bandwidth a. Set the CH 2 VOLTS/DIV switch to 1 m. b. Connect the CH 2 probe tip to the output of the Low Frequency Constant-Amplitude signal generator via a 50-ohm BNC 10X attenuator and a probe tip-to-BNC adapter. c. Adjust the signal generator for a six-division display for a one-kilohertz signal. d. Without adjusting the output amplitude, increase the output frequency until the display is reduced in amplitude to 4.2 divisions. e. CHECK-The signal generator output must be at least 100 kilohertz. f. Set the VOLTS/DIV switch to 2m and adjust the signal generator for a six-division display of a onekilohertz signal. g. Without adjusting the output amplitude, increase the output frequency until the display is reduced in amplitude to 4.2 divisions. h. CHECK-The signal generator output must be at least 200 kilohertz. i. Set the VOLTS/DIV switch to 5m and adjust the signal generator for a six-division display of a onekilohertz signal. j. Without adjusting the output amplitude, increase the output frequency until the display is reduced in amplitude to 4.2 divisions. k. CHECK-The signal generator output frequency must be at least 400 kilohertz. I. Set the VOLTS/DIV switch to 10 m and adjust the signal generator for a six-division display of a onekilohertz signal. m. Without adjusting the output amplitude, increase the output frequency until the display is reduced in amplitude to 4.2 divisions. n. CHECK-The signal generator output frequency must be at least 500 kilohertz. o. Remove CH 2 probe tip from the test setup. 15. Check CH 1 Vertical Amplifier Bandwidth a. Connect CH 1 probe tip to the test setup. b. Turn CH 2 POS to the OFF detent and CH 1 POS to midrange. c. Set the CH 1 VOLTS/DIV switch to 1 m. d. Repeat steps 14-c through 14-n.
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TM 9-6625-646-14&P TRIGGER CIRCUIT ADJUSTMENT Equipment Required 4. BNC to Banana Plug Adapter 5. Three-inch Screwdriver 6. Probe tip-to-BNC Adapter
1. Low Frequency Signal Generator 2. 42-inch 50-Ohm BNC Cable 3. BNC-T Connector
Control Settings Preset instrument controls to the settings given under Preliminary Control Settings except as follows: INTENSITY SEC/DIV CH 1 INPUT COUPLING CH 1 POS CH 2 POS Trigger SOURCE 16. Adjust AUTO PRESET a. Connect the CH 2 probe tip to the output of the Low Frequency signal generator via a BNC-T connector and a probe tip-to-BNC adapter. b. Adjust the signal generator for a 0.2 division display of a five-kilohertz signal. c. CHECK-For a stable display. d. ADJUST-AUTO PRESET, R375 (located on the side panel) for a stable display. 17. Check Trigger Circuit Operation Visible Display .1 m DC OFF Midrange CH 2 a. Set the CH 2 VOLTS/DIV switch to 1 V. b. Adjust the signal generator for a one-division display of a 500 kilohertz signal. c. Set the CH 2 VOLTS/DIV switch to 5 V. d. CHECK-A stable display can be obtained by adjusting the LEVEL/SLOPE control to trigger on both the positive-going and negative-going slopes of the displayed waveform. e. Return the LEVEL/SLOPE control to the AUTO PRESET detent. f. Set the Trigger SOURCE switch to COMP. g. CHECK-A stable display can be obtained by adjusting the LEVEL/SLOPE control to trigger on both the positive-going and negative-going slopes of the displayed waveform. h. Set the Trigger SOURCE switch to EXT and the LEVEL/SLOPE control to the AUTO PRESET detent. i. Connect the unused output of the BNC-T connector to the 212 EXT TRIG input via a 42-inch BNC cable and a BNC-to-banana plug adapter. j. CHECK-A stable display can be obtained by adjusting the LEVEL/SLOPE control to trigger on both the positive-going and negative-going slopes of the displayed waveform.
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TM 9-6625-646-14&P HORIZONTAL SYSTEM ADJUSTMENT Equipment Required 5. BNC-to-Banana Plug Adapter 6. Probe Tip-to-BNC Adapter 7. Three-inch Screwdriver
1. 2. 3. 4.
Standard Amplitude Calibrator Time-Mark Generator DC Voltmeter 42-inch 50-ohm BNC Cable
Control Settings Preset instrument controls to the settings given under Preliminary Control Settings except as follows: INTENSITY SEC/DIV CH 2 POS 18. Adjust Horizontal Centering a. Align dot to graticule center using HORIZ POS and CH 2 VERT POS control. b. Connect the DC voltmeter between pin 5 of U105 (positive meter lead to pin 5) and ground. (See Fig. 4-5 for test point and adjustment location.) Visible Display X-Y Midrange
c. CHECK-For a reading of 0 volts, +0.2 volt. d. ADJUST-Horizontal Centering, R366 for a meter reading of 0 volts +0.1 V. 19. Adjust HORIZontal GAIN a. Connect the CH 1 probe tip to the output of the Standard Amplitude Calibrator via a probe tip-to-BNC adapter. b. Set the Standard Amplitude Calibrator for a 20 millivolts output. c. Set CH 1 INPUT COUPLING switch to DC. d. CHECK-The CRT display for two dots separated horizontally by four divisions, +0.2 division. e. ADJUST-Horiz Gain, R475 (located on the side panel) for four divisions of deflection between dots. f. Disconnect all test equipment. 20. Adjust SWEEP CALibration a. Connect the CH 1 probe tip to the output of the Time-Mark generator via a probe tip-to-BNC adapter. b. Set the SEC/DIV switch to 1 m and the TimeMark generator for 1 millisecond markers. c. Set CH 2 POS to the OFF detent. d. Adjust the CH 1 VOLTS/DIV switch for a display approximately three divisions in amplitude.
Figure 4-5. Location of Horizontal Centering adjustment and test point.
4-10
TM 9-6625-646-14&P e. CHECK-The CRT display for one time mark per division. With the second time mark aligned with the second vertical graticule line, the tenth time mark should align with the tenth vertical graticule line within 0.4 division. f. ADJUST-SWEEP CAL, R370 (located on the side panel) for exactly eight divisions of deflection between the second and tenth time marks. 21. Check Horizontal Magnification Range a. Rotate the HOR IZ MAG control fully clockwise. b. CHECK-The CRT display for at least five divisions between adjacent time marks. Five-division spacing indicates a HORIZ MAG control range of at least 5:1. c. Return the HORIZ MAG control to the CAL detent. 22. Check SEC/DIV Accuracy a. CHECK-Apply the appropriate time marks and check each position of the SEC/DIV switch for proper timing over the center eight division portion of each sweep, within 0.4 division.
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TM 9-6625-646-14&P SECTION 5 TROUBLESHOOTING AIDS TROUBLESHOOTING AIDS Complete circuit diagrams are given in the rear of this manual. The component number and electrical value of each component in this instrument are shown on the diagrams along with important voltages. The portions of the circuit mounted on circuit boards are enclosed with blue lines. Component Color Coding The resistors used in this instrument are either composition resistors or precision resistors. The resistance values are color-coded on the components with EIA color-code (some precision resistors may have the value printed on the body). The color-code is read starting with the stripe nearest the end of the resistor. Composition resistors have four stripes which consist of two significant figures, a multiplier, and a tolerance value (see Fig. 5-1). Precision resistors have five stripes consisting of three significant figures, a multiplier, and a tolerance value. The capacitance values of common disc capacitors and small tubular electrolytics are marked in microfarads on the side of the component body. The molded electrolytic capacitors are color-coded in picofarads (see Fig. 5-1). The cathode end of each glass-encased diode is indicated by a stripe, a series of stripes, or a dot.
Figure 3-2 shows the location of the circuit boards within the instrument along with the assembly (A) numbers. The assembly numbers are also used on the diagrams to aid in locating the boards. Pictures of the circuit boards are shown in the Diagrams section, on the back of the page opposite the circuit diagram, to aid cross-referencing between the diagrams and the circuit board pictures. Each electrical component on the boards is identified by its circuit number as well as the interconnecting wires and/or connectors.
Figure 5-1. Color code for resistors, ceramic capacitors, and dipped tantalum electrolytic capacitors. 5-1
TM 9-6625-646-14&P
Figure 5-2. Lead configuration of semiconductors used in this instrument.
Semiconductor Lead Configuration Figure 5-2 shows the lead configurations of the semiconductors used in this instrument. such as a Triplett Model 630-NA or a Simpson Model 262. Use a dynamic transistor tester such as a TEKTRONIX Type 576 Transistor-Curve Tracer to check the semiconductor devices used in the 212. To check waveform(s) in this instrument, use a test oscilloscope with a DC to 500 kilohertz frequency response and one millivolt to 50 volts/division deflection factor.
Troubleshooting Equipment The majority of troubleshooting to be done on the 212 can be accomplished with a 20, 000 ohms/volt VOM
5-2
TM 9-6625-646-14&P SECTION 6 CIRCUIT DESCRIPTION The following circuit description begins with a discussion of the instrument using the block diagram located in the Diagrams section at the rear of this manual. Then each circuit is described in detail, using detailed diagrams where necessary to show the interconnections between the stages in each major circuit and the relationship of the side-panel controls to the individual stages. In addition to the block diagram, complete schematics are given in the Diagrams section. Generator circuit. The slope of the sawtooth signal is controlled by the SEC/DIV switch. The Sweep Generator circuit also produces an unblanking gate signal coincident with the sawtooth waveform. This gate signal unblanks the CRT to permit display presentation.
Block Diagram Signals to be displayed on the CRT are applied to the tips of the signal probes. The signals are then amplified by the appropriate channel Input Amplifier circuit, consisting of a two-section source-follower stage and two feedback amplifiers. The Input Amplifier circuits also contain the vertical deflection, position (with channel onOFF), input coupling, variable attenuation, and balance controls. The Trigger Generator circuit initiates the sweep signal produced by the Sweep Generator. The input signal to the Trigger Generator can be selected internally either from the capacitively coupled CH 2 Input Amplifier signal, or from the directly coupled COMPosite signal of the Feedback Amplifier. The Trigger Generator input signal can also be selected from the external signal applied to the EXT TRIG jack. The Trigger Generator circuit contains coupling and source controls in addition to a combination level/slope control. The Sweep Generator circuit produces a linear sawtooth output signal when initiated by the Trigger
The output of U370 is amplified by the Horizontal Amplifier circuit to produce the correct horizontal deflection for the CRT for all positions of the SEC/DIV switch. The Horizontal Amplifier contains a variable magnifier to increase the sweep rate up to at least a maximum of five times in any position of the SEC/DIV switch. The Power Supply and CRT circuits provide all the voltages necessary for operation of this instrument.
Circuit Operation In the following description of the electrical operation and relationship of the circuits in the 212, circuitry commonly used by TEKTRONIX is only briefly explained. If more information is desired on the commonly used circuits, refer to the following textbooks: Phillip Cutler, "Semiconductor McGraw-Hill, New York, 1964. Circuit Analysis",
Lloyd P. Hunter (Ed.), "Handbook of Semiconductor Electronics", second edition, McGraw-Hill, New York, 1962. Jacob Millman and Herbert Taub, "Pulse, Digital, and Switching Waveforms", McGraw-Hill, New York, 1965.
6-1
TM 9-6625-646-14&P Vertical Input Amplifiers Input signals for vertical deflection of the CRT of the 212 are applied to the tips of the attached probes. Each Input Amplifier provides control of input coupling, variable attenuation, vertical deflection factor, balance, and vertical position (with channel on-OFF) for the appropriate channel. Figure 6-1 shows a detailed block diagram of the Vertical Input Amplifier circuit. A schematic of this circuit is shown on diagram 1. positions .1 V/DIV and up, precision attenuators are used (in addition to changing the gain of U320-A and U320-B) to achieve the correct deflection factors. When the VOLTS/DIV VAR control is rotated, the signal is attenuated across R320 or R420. This offers variable (uncalibrated) deflection factors between the calibrated settings of the VOLTS/DIV switch. The STEP ATTEN BALance adjustments (R315 and R417) control the trace shift when switching between deflection factors.
Input signals applied to the tips of the probes are connected to the appropriate Attenuation Stage through the INPUT COUPLING switches (S305 and S405). The deflection factor in each channel is determined by the VOLTS/DIV switch (S310 or S410). In all positions of the VOLTS/DIV switches below .1 V/DIV, the correct deflection factor is achieved by changing the gain of Feedback Amplifiers U320-A and U320-B. In switch
The 212 can be operated single trace by turning either vertical POSition control to the OFF detent; this disables that channel in the last feedback stage of the Input Amplifier through the operation of the Vertical Mode Multivibrator U440. The CH 2 trigger signal is pr