Tektronix 067-0700-00 User manual

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Tektronix, Inc.
P.O. Box 500
Beaverton, Oregon 97005
070-1836-00
TEKTRONI»
INSTRUCTION MANUAL
Serial Number
First Printing JUNE 1974 ·

by Tektronlx, tnc.,
,Be"'vert(),i:ii:
inted in the United States of America. All
":rights re~~rved.Contents oft.his publication may not.
be<'~epte)ducedin any form without permission of
Tektrortix, Inc.
· lX.
products covered
•.tpatentspending.

067-0700-00
TABLEOFCONTENTS
SECTION 1 Characteristics
SECTION 2 Operating Instructions
r SECTION 3 Theory of Operation
SECTION 4 Maintenance
f" SECTION 5 Performance Check
SECTION 6 Diagrams
SECTION 7 Electrical Parts List
SECTION 8 Mechanical Parts List
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067-0700-00
Figure 1. 7D12 Calibration Fixture.
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Section 1-067-0700-00
CHARACTERISTICS
ELECTRICAL
SIGNAL INPUTS
Vertical Display
Termination Resistance 51 n, within 5%, 250 mW
In 7D12
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Scale Factor
Attenuator Setting
1 X 87 mV/div
2X
174 mV/div
5X 435 mV/div
Accuracy within 3%
Bandwidth ~100MHz
Aberrations +5%, -5%, total not to exceed 10% peak to peak
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Gate Waveform
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In 7D12
Termination Resistance 50 n, within 1.5%, 190 mW
Bandwidth
~
100 MHz
A/D Direct Input
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Range +2.0 V to -2.0 V
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Input Resistance 1 M.s1within 1%
Accuracy within 1%
Maximum Non-Destruct Input Voltage 1 kV peak between input connectors. 1 kV peak
between either connector and ground.
Common Mode Rejection Ratio (In 7D 12) 80 dB at 60 Hz (using 100 n unbalance in either input
connector)
Normal Mode Rejection Ratio (In 7D12) 50 dB at 60 Hz
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1-1

Characteristics-067-0700-00
SIGNAL OUTPUT
Readout Calibration
Output Current
Temperature Range
Altitude
Height
Width
Length
Weight
1-2
-0.9 mA, within
1%
with +15.0 V mainframe supply.
Varies linearly by -60µA/V with.the +15 V supply
ENVIRONMENTAL
0°C to 65°C
To 15,000 foot
PHYSICAL
6.5 cm (2.6 inches)
6.4 cm (2.5 inches)
20.4 cm (8.0 inches)
227 grams (8 ounces)
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Section 2-067-0700-00
OPERATINGINSTRUCTIONS
FUNCTIONS OF CONTROLS AND CONNECTORS
VERTICAL DISPLAY Connector
Provides a 50 .Q terminated direct input to the 7D12 vertical display.
GATE WAVEFORM Connector
Provides a direct input to the 7D12 50 .Q terminated gate waveform display.
Readout Mode Switch
READOUT CALIBRATION-Provides the channel 2 column with a constant current for the B's reference level, to
display a row of ten B's.
ATTEN READOUT CHECK-Allows the attenuator 1-2-5 readout to be displayed in channel 2.
A/D DIRECT INPUT Connectors
Provides a direct input for signals to the 7D12 A/D converter circuitry, and displays the readout in channel 1.
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Section 3-067-0700-00
THEORYOFOPERATION
INTRODUCTION
The following is a brief discussion of the basic operation of the major circuits in the 7D12 Calibration Fixture (067-
0700-00). The simplified block diagram in Figure 2 and on the schematic is provided to aid in understanding this discussion.
GATE WAVEFORM DIRECT INPUT
The gate waveform signal is routed directly from connector J1 to the 7D12 (50-ohm terminated input) gate waveform
display circuit.
VERTICAL DISPLAY DIRECT INPUT
The vertical display signal is routed from connector J4 to the 7D12 vertical display circuit. Resistor RBprovides
proper signal termination and R7 provides damping.
ATTENUATOR READOUT CHECK
This calibration fixture provides an interconnection from the 7D12 attenuator switch to the readout system. The
readout system displays the amount of attenuation (1, 2, or 5 times) as determined by the attenuator switch setting.
READOUT CALIBRATION
Integrated circuit U16 provides a precise 900 microampere current through the 7D 12 to the readout system. When
the proper calibration current is present, ten B's appear in the channel 2 readout position (lower readout).
U16 is an operational amplifier used as a current converter. Negative feedback, provided through R14, attempts to
stabilize the negative input with the positive input level. Loading variations (from about Oto -300 millivolts), control the
positive input level with positive feedback through R18.
A/D DIRECT INPUT
Input signals are routed to connectors J21 (positive) and J24 (negative). A 1 megohm input termination is provided
by R23 and R24. Resistor R22 protects the 7D12 input against excessive input voltage. Signal filtering is provided by C24
and C25. Decimal-point encodin9 for channel 1 is provided by R28 and R32. The V suffix is encoded by R30 and H34.
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Theory of Operation-067-0700-00
IN
OUT
3-2
GATE
WAVEFORM
DIRECT
INPUT
VERTICAL
DISPLAY
DIRECT
l!\IPUT
READOUT
CALIBRATION
ATTEN
READOUT
CHECK
AID
DIRECT
INPUT
~
!BLACK!
J1
~
J4
~
------------------------------~ b10 GATE DISPLAY
-------------------11TERl~E~riONI t-------->~b20 SIGNAL DISPLAY
~
r-----------------------------__:~b6 1, 2, 5 SCALE
FACTOR DISABLE
S11 OUT u COMPENSATED
PRECISION
CURRENT
SOURCE
1------- U16
b12 CH2COLUMN
J21 a1 VHIGH
1 MEGOHM INPUT a2 GUARD
TERMINATION
J24 AND FILTER. b2 FGUARD
b1 VLOW
b14 CH 1 COLUMN
READOUT
ENCODING b15 CH 1 ROW
RESISTOR
NETWORK a13 TSB
.a20 TS 1
1836-2
Figure 2. Block Diagram.
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Section 4-067-0700-00
MAINTENANCE
INTRODUCTION
This section of the manual contains information for use in preventive maintenance, corrective maintenance, and trouble-
shooting of the 7D12 Calibration Fixture.
Further maintenance information relating to component color codes and soldering techniques can be found in the
instruction manuals for the 7000-Series oscilloscopes.
PREVENTIVE MAINTENANCE
Preventive maintenance, performed on a regulat basis, will improve the reliability of this instrument. Periodic checks
on the semiconductor devices used in the unit are not recommended as a preventive-maintenance measure. See semiconductor-
checking information given under Troubleshooting.
CLEANING
Front Panel
CAUTION
Avoid the use of abrasive or chemical cleaning agents that might damage
the plastics or dissolve the lubricants used in this instrument. Do not use
benzene, toluene, xylene, acetone, MEK, MIBK, carbon tetrachloride,
triclor, trichlene, methylalcohol, methylene chloride, sulfuric acid, Freon
TA-TC-TE-TF-12-22, or similar solvents.
Loose dust may be removed with a soft cloth or a dry brush. Water and mild detergent may also be used.
Interior
Use low-velocity compressed air to blow off the accumulated dust. Remove stubborn dirt with isopropyl alcohol,
petroleum ether, white kerosene, or a solution of 1% mild liquid detergent and 99% water.
PERFORMANCE CHECK
The Performance Check procedure can be helpful in isolating major troubles in the unit. Moreover, minor troubles not
apparent during regular operation may be revealed and corrected.
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Maintenance-067-0700-00
TROUBLESHOOTING
The following information is provided to aid in troubleshooting the 7D12 Calibration Fixture. The schematic, Theory
of Operation and Performance Check sections can also be used to troubleshoot this instrument. The Theory of Operation
section gives detailed information on circuit behavior and output requirements.
TROUBLESHOOTING AIDS
Diagrams
A circuit diagram is given on a foldout page. The circuit number and electrical value of each component in this instru-
ment are shown on the diagram. Important voltages are also shown.
Circuit Board
The circuit board used in the 7D12 Calibration Fixture is outlined on the diagram, and a drawing of the board-mounted
components is shown in the back with the diagram; each board-mounted electrical component is identified by its cirucit
number.
Component and Wiring Color Code
Colored stripes or dots on resistors and capacitors signify electrical values, tolerances, etc., according to the EIA
standard color code. Components not color coded usually have the value printed on the body.
TROUBLESHOOTING EQUIPMENT
A voltmeter for checking voltages within the circuit and an ohmmeter for checking resistors, capacitors, and diodes is
useful for troubleshooting the 7D12 Calibration Fixture. A Tektronix DM 501 Digital Multimeter with Power Module is
recommended.
TROUBLESHOOTING PROCEDURE
The following procedure is recommended for effectively troubleshooting the 7D12 Calibration Fixture.
1. CHECK CONTROL SETTING.
An incorrect control setting or input can indicate a trouble that does not exist. If there
is any question about the correct function or operation of a control or front-panel connector, see Operating Instructions.
2. CHECK ASSOCIATED EQUIPMENT.
Before proceeding with troubleshooting, check that the equipment used with the
Calibration Fixture is operating correctly. If possible, substitute equipment known to be operating correctly and see if the
problem persists. Check that the inputs are properly connected and that the interconnecting cables are not defective.
3. VISUAL CHECK.
Visually check the instrument. Many troubles can be located visually, such as unsoldered connections,
broken wires, damaged circuit board, or damaged components, etc.
4. CHECK INSTRUMENT PERFORMANCE.
Localize the trouble to a circuit by using the Performance Check procedure.
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Maintenance-067-0700-00
5. CHECK VOLTAGES. Often the defective component or stage can be located by checking for the correct voltage in the
circuit. Typical voltages are given on the schematic and might vary slightly between instruments, To obtain operating condi-
tions similar to those used to take these readings, see the instructions in the Diagram section.
6. CHECK INDIVIDUAL COMPONENTS. The following methods are provided for checking the individual components in
the 7D12 Calibration Fixture. Components that are soldered in place are best checked by disconnecting one end to isolate
the measurement from the effects of surrounding circuitry.
IntegratedCircuits (IC's). A good understanding of the circuit is essential to troubleshooting circuits containing IC's. IC's can
be checked with a voltmeter, test oscilloscope, or by direct substitution. Use care when checking voltages around the IC's so
that adjacent leads are not shorted together. When substituting a suspected component, check that circuit conditions are
normal so that the replacement IC will not also be damaged. Be sure the power is off before attempting to remove or re-
place any IC.
Diodes. A diode can be checked for an open or shorted condition by measuring the resistance between terminals. With an
ohmmeter scale having an internal source of between 800 millivolts and 3 volts, the resistance should be very high in one
direction and very low when the leads are reversed.
CAUTION
Do not use an ohmmeter scale that has a high internal current source.
High currents may damage the diodes.
Resistors.Check resistors with an ohmmeter. Resistor tolerance is given in the Electrical Parts List. Resistors normally do
not need to be replaced unless the measured value varies widely from the specified value.
Capacitors. A leaky or shorted capacitor can be detected by checking resistance with an ohmmeter on the highest scale. Use
an ohmmeter that will not exceed the voltage rating of the capacitor. The resistance reading should be high after the initial
charge of the capacitor. An open capacitor can best be detected with a capacitance meter, or by checking whether the
capacitor passes ac signals.
7. REPAIR AND CHECK THE CIRCUIT. Special techniques required to replace components in this unit are given under
Component Replacement. Be sure to check the performance of any circuit that has been repaired or that has had any
electrical components replaced.
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Maintenance-067-0700-00
REPLACEMENT PARTS
STANDARD PARTS
All electrical and mechanical replacement parts for the 7D12 Calibration Fixture can be obtained through your local
Tektronix Field Office or representative. However, manv._ofthe standard electrical components can be obtained locally in
Jesstime than is required to order them from Tektronix, Inc. Before purchasing or ordering replacement parts, check the
parts list for value, tolerance, ratin.9, and description.
SPECIAL PARTS
NOTE
When selecting replacement parts, it is important to remember that the
physical size and shape of the component may affect its performance in
the instrument. All replacement parts should be direct replacements
unless it is known that a different component will not adversely affect
the instrument performance.
Some parts are manufactured or selected by Tektronix to satisfy particular requirements, or are manufactured for
Tektronix to our specifications. Most of the mechanical parts used in this instrument have been manufactured by Tektronix.
To determine manufacturer of special parts, refer to Parts List, Gross Index Mfr. Code Number to manufacturer. Order all
special parts directly from your local Tektronix Field Office or representative.
ORDERING PARTS
When ordering replacement parts from Tektronix, Inc., refer to the Parts Ordering Information and Special Notes and
Symbols on the page immediately preceding the Electrical Parts List section. Include the following information:
1. Instrument type (067-0700-00).
2. Instrument serial number.
3. A description of the part {if electrical, include the circuit number).
4. Tektronix Part Number.
SOLDERING TECHNIQUES
The following rules should be observed when removing or replacing parts:
1. Use small soldering iron (not over 15 watts on circuit boards).
2. Do not apply more heat, or apply heat for a longer time, than is absolutely necessary.
3. Clean parts as described under Cleaning.
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Maintenance-067-0700-00
COMPONENT REPLACEMENT
The exploded-view drawinq associated with the Mechanical Parts List may be helpful when disassembling or reassembl-
ing individual components or sub-assemblies.
CIRCUIT-BOARD REMOVAL
In general, the circuit board used in the 7D12 Calibration Fixture need never be removed unless the board must be re-
placed. When it becomes necessary to remove the circuit board assembly, use the following procedure:
1. Remove rear two screws holding side panels and slide out to remove side panels.
2. Disconnect both coaxial cables. These cables have plugs on both ends.
3. Remove four screws securing rear plate to frame.
4. Remove retaining clip from rear of module-retaining screw, and slide out module-retaining
screw from the front.
5. Rotate rear plate and slide over circuit-board connector.
6. Remove nuts on banana jacks using 3/8-inch wrench.
7. Pull circuit board out.
CIRCUIT BOARD REPLACEMENT
NOTE
To maintain the correct input polarity, the black banana jack should be
on the switch side of the circuit board.
1. Bend new solder lugs to match the original solder lugs. Place solder lugs on banana jacks. Place
nuts over the solder lugs and finger tighten.
2. Place circuit board tightly against front panel. Align solder lugs on circuit board, then solder to
circuit board.
3. Tighten nuts on banana jacks.
4. Reverse the order of the first five steps of the removal procedure to assemble module.
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Maintenance-067-0700-00
INTEGRATED CIRCUIT REPLACEMENT
CAUTION
Usecare when removing integrated circuits to prevent lead damage.
PERFORMANCE CHECK AFTER REPAIR
After any electrical component has been replaced, the performance of that particular circuit should be checked. The
Performance Check procedure provides a quick and convenient means of checking instrument operation.
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Section5-067-0700-00
PERFORMANCECHECK
INTRODUCTION
The following procedure checks the performance of the 7D12 Calibration Fixture. All tolerances given in this proce-
dure are intended to indicate proper operation only and should not be interpreted as instrument specifications.
TABLE 5-1
Test Equipment Required
DESCRIPTION MINIMUM USAGE EXAMPLES OF APPLICABLE
SPECIFICATIONS TEST EQUIPMENT
1. Indicator Oscilloscope Tektronix 7000-Series Oscillo- Used throughout pro- a. Tektronix 7704A Oscilloscope
scope equipped with a readout cedure to provide a System.
system and a calibrator square- display and square-wave
wave output, 0.2 V and 0.4 V calibrator signal. b. Tektronix 7904 Oscilloscope.
p-p into 50
n.
2. 7D12 A/D Converter Used throughout a. Tektronix 7012 A/O
procedure. Converter.
3. Time-base Unit Tektronix 7-B Series. Used throughout a. Tektronix 7B53A Dual Time
procedure to provide Base.
sweep. b. Tektronix 7B92 Dual Time
Base.
C.
Tektronix 7B70 Time Base.
4. Cable, Special Purpose Connectors, pin-jack to BNC Calibrator pin-jack a. Tektronix Part No. 175-1178-
male; length, 20 inches. signal coupling. Need 00.
depends on oscillo-
scope calibrator output.
5. 50
D
Coaxial Cable Impedance 50
D;
length, 42 Used through proce- a. Tektronix Part No. 012-0057-
inches; connectors, BNC male. dure for signal coupling. 01.
6. Adapter Jack Connectors, dual banana plug Used in procedure for a. Tektronix Part No. 103-0090-
to female BNC. coupling of coaxial 00.
cable to banana jacks.
® 5-1

Performance Check-067-0700-00
INDEX TO PERFORMANCE CHECK
Preliminary Procedure for Performance Check
VERTICAL DISPLAY
1. Check Display Attenuator Readout and Gain Accuracy
2. Check Readout Calibration
VOLTAGE READOUT DISPLAY
3. Check A/D Direct Input
GATE DISPLAY
4. Check Gain Accuracy
PRELIMINARY PROCEDURE FOR PERFORMANCE CHECK
NOTE
The performance of this instrument can be checked at any temperature
within 0°C to +50°C unless stated otherwise.
Page
5-3
5-3
5-4
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5-4
5-5
5-5
1. Insert 7D12 Calibration Fixture in 7D12 and install both in either vertical plug-in compartment of indicator oscil-
loscope.
2. Install time-base unit in horizontal compartment of indicator oscilloscope.
3. Connect indicator oscilloscope to power source that meets the voltage and frequency requirement of the oscillo-
scope.
4. Turn indicator oscilloscope on. Allow at least twenty minutes warmup before checking 7D12 calibration fixture
performance.
5. Set indicator oscilloscope readout and intensity controls for a usable readout display on the crt. A/D direct input
readout display should appear in the upper graticule divisions. Vertical display attenuation factor or ten 8's should appear in
lower graticule divisions in a location corresponding to plug-in compartment used.
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Performance Check-067-0700-00
VERTICAL DISPLAY
EQUIPMENT REQUIRED
1. Indicator oscilloscope
2. 7D12 A/D Converter
3. 50 ohm coaxial cable
1. Check Display Attenuator Readout and Gain Accuracy
a. Set controls asfol lows:
7D12 Calibration Fixture
ATTEN READOUT CHECK
Vertical Display Atten
Triggering
Gate
7D12
b. Position trace two divisions below center graticule line.
OUT
1 X
Auto
Out-Off
c. Connect a 400 millivolt, 1 kilohertz signal from oscilloscope calibrator to VERTICAL DISPLAY DIRECT INPUT
connector of calibration fixture.
d. CHECK-Set 7D12 Vertical Display Atten switch to settings given in Table 5-2. Display amplitude and lower numeri-
cal readout display should be within limits for each switch setting listed in Table 5-2.
TABLE 5-2
Vertical Display Amplitude and Lower Numerical Readout
7D12 Display Amplitude Lower Numerical
Vertical Display (Divisions) Readout Display
Atten Switch Min. Max
1 X 4.4 4.8 1
2X 2.2 2.4 2
5X 0.87 0.97 5
e. Disconnect calibrator signal
5-3

PerformanceCheck-067-0700-00
2. Check Readout Calibration
a. Set controls as follows:
7D12 Calibration Fixture
READOUT CALIBRATION IN
Controls not mentioned can be set as desired.
b. CHECK-Lower numerical readout display for a row of ten 8's.
VOLTAGE READOUT DISPLAY
EQUIPMENT REQUIRED
1. Indicator oscilloscope
2. 7D12 A/D Converter
3. 50 ohm coaxial cable
4. Dual banana-plug to female BNC adapter
3. CheckA/D Direct Input
a. Set controls as follows:
7D12 Calibration Fixture
ATTEN READOUT CHECK OUT
7D12
Triggering Auto
Controls not mentioned can be set as desired.
b. CHECK-Voltage Readout display for a reading of approximately zero volts.
c. Connect a 4 volt, 1 kilohertz signal from oscilloscope calibrator to calibration fixture A/D DIRECT INPUT jacks.
d. CHECK-Voltage Readout display shoJld read approximately +2 volts (depending upon accuracy of oscilloscope
calibrator).
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