Tektronix 7A21N User manual

Tektronix, lnc.
P.O. Box
500
Beaverton, Oregon 97005
INSTRUCTION MANUAL
Serial Number
---
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Tektronix, Inc.
P.O. Box
500
Beaverton, Oregon 97005
070-1367-00
TEKTRONI~
7A21N
DIRECT ACCESS
INSTRUCTION MANUAL
Se ri al Number
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WARRANTY
All TEKTRONIX instruments are warranted apinst
defective materials and workmanship for one year. Any
questions
with respect to the warranty should be taken up
with your TEKTRONIX Fteld Engineer or representative.
All requests for repairs and replacement
part s should be
directed 10 the TEKTRONIX Field Office or represe nl at iv.
in your area. This will assure you the faslest po ssi bl.
service. Please include the ins trument Typ e Number or Part
Number a
nd Serial Number with a ll requ ests for parts or
service.
Specifications and Pfice change privileges reserved.
Copyright ®
1972 by Te ktroni x, lnc ., Beave rton , Oregon.
Printed in
the United States of America. All rights reserved.
Contents of this publication may not be reproduced in any
form
without permi ss ion of Tektronix, Inc.
U.S.A. and foreign TEKTRONIX
products covered by U.S.
and foreign
patents andl or patents pending.
TEKTRONIX
is a registered trademark of Tektr onix, Inc.
ScaM bv OIl/sOlIrce-Optio"5 ->

TABLE OF CONTENTS
Operating Instructions
lnstallation
General Operating lnstructions
Specifications
Circuit Description
Maintenance
Calibration
Performance Check
Electrical Parts List
7A21 N Diagram
Mechanical Parts List
Page
1
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7A21N
TABLE OF CONTENTS
Page
Operating Instructions 1
Installation 1
General Operating Instructions 4
Specifications 5
Circuit Description 5
Maintenance 6
r Calibration 7
Performance Check 7
Electrical Parts List
11
7A21N Diagram
<Y
Mechanical Parts List 13
®

7A21 N Features
The 7A21N Direct Access plug-in is designed for use with TEKTRONIX 7900-Seriesoscilloscopes. This unit provides
AC coupling of high-frequency or fast-risetime signals directly to the CRT vertical deflection plates. Two front-panel
input connectors permit either single ended or differential operation (internally selected). Trace positioning is accom-
plished with a front-panel control.
@
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7A21N Features
POSITION
DIfFERENTIAL
MODE
+INPlIT
E
MODE D£TERMINED
BV INTERNAL
CDNNECT I ONS
SINGLE EHOEO
MODE
INPUT
NOT
CONNECTEO
DIRECT ACCESS
7A21N~ h ______________ ~U
The 7A2 1N Direct Access plug· in is designed f or use with TEKTRONI X 7900 ·Series oscilloscopes. This unit provides
AC coupling of high-frequency or fast-risetime signals directly to the CRT vertical deflection plates. Two front·panel
input connectors permit either single ended
or differential operation (internally se le cted). Trace positioning is accom-
plished with a front-panel control.
7A21N ®

OPERATING INSTRUCTIONS
General
the 7A21N CRT Termination assembly. The CRT Input
Network and 7A21N CRT Termination assembly are
effectively use the 7A21N* the 'peration and
provided as standard accessories and are stored on the left
capabilities of the instrument must be known. This section
side of the 7~21~, see ~i~. 1. cableand wire assemblies are
gives installation procedures, describes front panel controls, provided
to connect the signal and the position control
and gives general information On operation and signal voltages
to the CRT deflection plates. The parts of the
connections. mainframe affected by this installation and their relative
locations are shown in the before and after illustrations in
INSTALLATION
Fig. 2.
The 7A21N is designed to operate in the Left Vertical
Procedure
plug-in compartment of TEKTRONIX 7900-Series oscillo-
scope mainframes. When shipped from the factory, this Preliminary
instrument has been calibrated to meet the tolerances listed
in the Performance Requirement column in the Specifica- 1. Disconnect the mainframe from the power source.
tion section. 2. Remove all plug-in units from the vertical compart-
ments.
Installation includes replacing the mainframe Vertical
Amplifier board with the 7A21N CRT Input Network and
3. Remove the left side panel from the mainframe.
Fig. 1. Standard accessories supplied with 7A21N.
1
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7A21N
OPERATING INSTRUCTIONS
General
To effectively use the 7A21N, the operation and
capabilities
of the instrument must be known. This section
gives installation procedures, describes front panel controls,
and gives general information on operation and signal
connections.
INSTALLATION
The 7A21N is designed to operate in the L eft Vertical
plug-in compartment of TEKTRON IX 7900-Series oscillo-
scope mainframes. Wh
en shipped from the factory, this
instrument has been calibrated to meet the tolerances listed
in the Performance Requirement column in the Specifica-
tion section.
Installation includes replacing the mainframe Vertical
Amplifier board with the 7A21N CR T Input Network and
Eltlenlion
Cabl"
Input
I
'-..r
Positioning
Wire
Asse
mbly
the 7A21 N CRT Termination assembly. The CRT Input
Network and 7A21N CRT Termination assembly are
provided as
standard accessories and are stored on the left
side
of the 7A2 1N , see Fig. 1. Cable and wire assemblies are
provided to
connect the signal and the position control
voltages to the CRT deflection plates. The parts of the
mainframe affected by this installation and their relative
l
ocations are shown in the before and after illustrations in
Fig. 2.
Installation Procedure
Preliminary
1. Disconnect
the mainframe from the power source.
2. Remove all plug·in
units from the vertical compart·
ments.
3. Remove the left side panel from the mainframe.
7A21NCRT
Termination Assemblv
son
T ... mination
=- =-
=- =-
Standoff,
IIII
TEKTRONIX to
TEKTRONIX
AQp11lu
Clamp and
Mounting
H.rdwa ..
Fig. 1. Standard accessories supplied with 7A21 N.
® 1

Before
After
JllO
(brown on blue cable)
7A21N CRT
Vertical Amplifier
ck on blue cable)
Fig. 2. Shows board positionsand cable connections Fig.
3. Installation of positioningwire assembly.
before
and after installation of 7A21N.
8
2
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7A21N
Before
After
2
Fig. 2. Shows board positions and cable connection~
before and after installation of 7A21N.
(Red on Blue)
J110
(brown on blue cable)
J112
(red on blue cable)
7A21N CRT
Termination
Assembly
Positioning
gg.~;;:::- __ -- Wire
Assembly
J152
(blue cable)
J150
(black on blue cable)
Clamp
Fig. 3. Installation of positioning wire assembly.
®

Move Vertical Amplifier Board
4. Remove the nine screws securing the Vertical Ampli-
fier board to the mainframe. Disconnect the vertical
deflection plate leads from the CRT. Disconnect all cables
and connectors from the Vertical Amplifier board except
the cables connected to J660 and J661.
5. Install the four standoffs (shown in Fig. 1) in the
holes on the chassis. These standoffs are used to mount the
Vertical Amplifier board to the rear of the boards original
position. The three cables to be connected to the top left
corner of the Vertical Amplifier board will have to be
re-routed to accommodate the new board location. Secure
the board to the standoffs using four of the nine screws
removed in step 4. Reconnectthe 3 cables connected to the
top left of the board and the 2 pin connector.
NOTE
If the red on white wire of the2-pinconnector is too
short to allow the connector to seat, replace it with
one supplied with the
7A2 1 N.
Install CRT lnputNetwork
6. Remove the CRT lnput Network assembly from the
storage space in the 7A21N (see Fig. 1). Mount the CRT
lnput Network assembly to the chassis, using four of the
nine screws removed in step 4. Refer to Fig. 2 for exact
board locations.
7. Connect the leads located on the underside of the
CRT lnput Network to the vertical deflection plate pins.
After these leads are connected, lightly pull on each lead to
be sure it will remain connected. These leads should be
dressed close to each other to obtain optimum high
frequency characteristics.
Use care when handling the CRTpin connectors. The
CRTpinsmay break if thepins are bent.
ReplaceCRT Termination Assembly
8. Remove the two screws securing the CRT Termina-
tion assembly to the oscilloscopechassis, refer to Fig. 2 for
location. Disconnect the pin connectors from the CRT
Termination assembly and the CRT. Remove the CRT
Termination assembly.
9. Remove the 7A21N CRT Termination assembly from
the storage space in the 7A21N, see Fig. 1. Mount the
7A21N CRT Termination assembly to the oscilloscope
chassis, using the hardware removed in step
8.
10. Connect the leads located on the underside of the
7A21N CRT Termination assembly to the CRT deflection
plates. Lightly pull on each lead to be sure it will remain
connected.
Connect Cables and Connectors
11. Move the cable connected to J660 (blue)to J152 on
the CRT lnput Network, see Fig. 2.
12. Move the cable connected to J661 (black on blue)
to J150 on the CRT lnput Network, see Fig. 2.
13. Move the multi-pin connector, P794, (previously
connected to J794 on the Vertical Amplifier board) to
J154 on the CRT lnput Network. The connector index
(end with brown lead) should be toward the rear of the
oscilloscope.
14. Remove the cable connected to J604 (brown on
blue) and connect itto J110 on the CRT lnput Network by
using the TEKTRONIX to TEKTRONIX adapter1 and the
brown on blue extension cable. See Fig. 2.
15. Remove the cable connected to J601 (red on blue)
and connect
it to J112 on the CRT lnput Network by using
the TEKTRONIX to TEKTRONIX adapter1 and the red on
blue extension cable. See Fig. 2.
16. Clamp the two cables installed in steps 14 and 15 to
the chassis, using the clamp and hardware supplied with the
7A21N. See Fig. 2.
17. Insert the connectors of the Positioning Wire
assembly into sockets J5-3 and J5-4, located on the
oscilloscope interface connector. Refer to Fig. 2 and
close-up in Fig.
3. Push the connectors into the sockets
until they snap into place.
It may be necessary to use a pair
of long-nose pliers or tweezers to push the sockets until
they extend beyond the plastic housing. These connectors
are now permanently installed and cannot be removed.
18. Connect the multi-pin connector end of the Posi-
tioning Wire assembly to J120 of the CRT Termination
'In some earlier oscilloscope models, SEALECTRO connectors are
used. In these cases, the 7A21N can be equipped with special
SEALECTRO cable assemblies. Consult your TEKTRONIX Field
Engineer or Representative for details.
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Move Vertical Amplifier Board
4. Remove the nine screws securing the Vertical Ampli-
fier
board to the mainframe. Disconnect the vertical
deflection plate leads from
the CRT. Disconnect all cables
and connectors from the Vertical Amplifier board except
the cables connected to J660 and J66l.
5. Install the four standoffs (shown in Fig. 1) in the
holes on the chassis. These standoffs are used to mount the
Vertical Amplifier board to the rear of the boards original
position.
The three cables to be connected to the top left
corner of the Vertical Amplifier board will have to be
re-routed
to accommodate the new board location. Secure
the board to the standoffs using four of the nine screws
removed
in step 4. Reconnect the 3 cables connected to the
top left of the board and the 2 pin connector.
NOTE
If the red on white wire of the 2-pin connector is too
short to allow the connector to seat, replace
it with
one supplied with the 7
A21 N.
Install CRT Input Network
6. Remove the CRT Input Network assembly from the
storage space in the 7A21N (see Fig. 1). Mount the CRT
Input Network assembly to the chassis, using four of the
nine screws removed in step 4. Refer to Fig. 2 for exact
board locations.
7.
Connect the leads located on the underside of the
CRT Input Network to the vertical deflection plate pins.
After these leads are
connected, lightly pull on each lead to
be sure it will remain connected. These leads should be
dressed close
to each other to obtain optimum high
frequency characteristics.
Use care when handling the CRT pin connectors. The
CRT pins may break if the pins are bent.
Replace CRT Termination Assembly
8. Remove the two screws securing the CRT Termina-
tion assembly to the oscilloscope chassis, refer to Fig. 2 for
location. Disconnect
the pin connectors from the CRT
Termination assembly and the CRT. Remove the CRT
Termination assembly.
9. Remove
the 7A21 N CRT Termination assembly from
the storage space in the 7A21N, see Fig. 1. Mount the
7A21N
7A21N CRT Termination assembly to the oscilloscope
chassis, using
the hardware removed in step 8.
10.
Connect the leads located on the underside of the
7A21N CRT Termination assembly to the CRT deflection
plates. Lightly pull on each lead
to be sure it will remain
connected.
Connect Cables and Connectors
11. Move the cable connected to J660 (blue) to J152 on
the CRT Input Network, see Fig. 2.
12. Move
the cable connected to J66l (black on blue)
to J150 on the CRT Input Network, see Fig. 2.
13. Move
the mUlti-pin connector, P794, (previously
connected to J794 on the Vertical Amplifier board) to
J154 on the CRT Input Network. The connector index
(end with
brown lead) should be toward the rear of the
oscilloscope.
14. Remove
the cable connected to J604 (brown on
blue)
and connect it to Jll0 on the CRT Input Network by
using
the TEKTRON IX to TEKTRON IX adapter
l
and the
brown on blue extension cable. See Fig. 2.
15. Remove
the cable connected to J60l (red on blue)
and
connect it to Jl12 on the CRT Input Network by using
the TEKTRON IX to TEKTRON IX adapter
l
and the red on
blue
extension cable. See Fig. 2.
16. Clamp
the two cables installed in steps 14 and 15 to
the chassis, using the clamp and hardware supplied with the
7A21 N. See Fig. 2.
17. Insert
the connectors of the Positioning Wire
assembly
into sockets J5-3 and J5-4, located on the
oscilloscope interface connector. Refer to Fig. 2 and
close-up in Fig. 3. Push the connectors into the sockets
until
they snap into place. It may be necessary to use a pair
of long-nose pliers or tweezers to push the sockets until
they extend beyond the plastic housing. These connectors
are now permanently installed and cannot be removed.
18.
Connect the multi-pin connector end of the Posi-
tioning Wire assembly
to J120 of the CRT Termination
lin some earlier oscilloscope models, SEALECTRO connectors are
used. In
these cases, the 7A21N can be equipped with special
SEALECTRO cable assemblies. Consult your TEKTRONIX Field
Engineer
or Representative for details.
3
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assembly. The connector index (end with brown on white however, should be disconnected and placed where
it will
lead)should be toward the bottom of the oscilloscope. not interfere with operation of this mainframe.
19. Fully insert the 7A21N into the oscilloscope Left
Vertical compartment. This completes the installation
procedures for the
7A21N.
Removal
To use other plug-in units in the Vertical compartments
of the mainframe, it
is necessary to remove the parts added
for direct-access operation with the exception of the
Positioning Wire assembly. The connector ends of this
assembly are permanently installed and should not be
removed. The multi-pin connector end of this assembly,
GENERAL OPERATING INSTRUCTIONS
Modes of Operation
The 7A21N can be connected (internally) for single-
ended operation of differential operation. The illustrations
shown in Fig.
4 show the internal cable connections used
for the single ended and differential modes of operation.
When used in the differential mode and if only one input
is used, the other input should be terminated into 50 a. It
is always good practice to terminate the unused input. Use
the 50 Terminator supplied with the
7A21N.
Fig. 4. Cable connections for single-ended and differential operation.
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7A 21N
assembly. T
he connector index (end with brown on white
lead) should be toward the bottom of the oscilloscope.
19.
Fully insert the 7A2 1N into the oscilloscope L eft
Vertical compartment. This completes the installation
procedures
for the 7A2 1N.
Remov al
To use other plug -i n units in the Vertical compartments
of the mainframe, it is necessary to remove the parts added
for direct-access operation
with the exception of the
Positioning Wire assembly. The connector
ends of this
assembly are permanently installed and should
not be
removed. The
multi -pin connector end of this assembly,
however, should
be disconnected and placed where it will
not interfere with operation of this mainframe.
GENERAL OPERATING INSTRUCTIONS
Modes of Operation
T he 7A2 1N can be connected (internally) for single·
ended operation
of di ff erential operation. T he illustrations
sh own in Fig. 4 sh ow the internal cable connections used
for the si ngle ended and differential modes of operation.
When used
in the differential mode and if only one input
is used, the other input should be terminated i nto 50 n. It
is always good practice to terminate the unused input. Use
the 50 n Terminator supplied with the 7A2 1 N.
Fig. 4. Cable c onn ec tion s for single·e nded and diffe renti al o pe ra tion.
4 ®
ArtekMedia
Digitally signed by ArtekMedia
DN: cn=ArtekMedia, o=ArtekMedia.com, ou, [email protected], c=US
Date: 2008.11.16 19:15:44 -06'00'

SPECIFICATION
The following electrical characteristics are valid for instrumentscalibrated at an ambient temperaturebetween+20°c and
+30°c after a20 minute warmup period.
TABLE
1-1
ELECTRICAL CHARACTERISTICS
CIRCUIT DESCRIPTION
The 7A21N circuitry is explained first as internally
connected for the differential mode of operation, then as
internally connected for the single-ended mode of opera-
tion.
It should be noted that the entire signal line is
designed to maintainaconstant impedance of 50 a.
SupplementalInformation
Using a reflectometer with a system
risetimeof 75 ps.
Characteristic
Deflection Factor
Single Ended Mode
Differential Mode
Bandwidth
Maximum Input Power
(Each Input)
Input Impedance
(Each Input)
ReflectionCoefficient
The signal connected to the -INPUT
is AC coupled
through C18 and inverted in L21. The signal
is invertedto
provide proper phasing with the +INPUT signal. After
inversion, the signal is algebraically added to the +INPUT
signal in the 50 Bridge, U12. The characteristics of this
bridge are such that each input
is terminatedinto50 and
the output of the bridge has
a source impedance of 50 a.
PerformanceRequirement
Less than four volts/division
Less than ten volts/division
20 kilohertz to one gigahertz
Six watts average; 200 volts DC
50 ohms, AC coupled
0.1 peak-to-peak
C
The signal connected to the +INPUT is AC coupled
through C5, then connected to U12 through the delay line,
L6. The delay time of L6
is calculated so that the transit
L -
time from the +INPUT connector to U12 is the same as the
transit time from the -INPUT connector to U12.
The output of the 50
fl Bridge assembly, U12, is
connected to the compensatingnetwork composed of R24,
C24, R25, C25, R26, and L26. This network compensates
for the skin effect losses and line losses in U12 and the
cables.
Power divider U30 splits the signal into two directions.
The characteristics of the Power Divider are such that,
when properly terminated, the impedance looking into any
leg
is 50 a.
The output of U30 at J31 is inverted at L56. Com-
ponents R61, C61, R62, C62, R63, and L63 compensate
for skin effect losses and line losses of the cables, the
Inverter, and the Power Divider. The signal
is then
capacitively coupled to the CRT deflection plate. The
output of U30
at J30 is connected to the delay line L36.
Delay time for L36 is calculated so that the transit times of
the inverted and non-invertedsignals are equal. R41, C41,
R42, C42, R43, and L43 compensate for the skin effect
losses and line losses of the cables, delay line and Power
Divider. The non-invertedsignal is connected to the CRT
lnput Network where
it is capacitively coupled to the CRT
vertical deflection plate. The 69 resistors on the CRT
lnput Network parallel the 182.5 impedance of the
deflection plates to form 50
a termination for the inverted
and non-invertedsignals.
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7A21N
SPECIFICATION
The following electrical characteristics are valid for instruments calibrated at an ambient temperature between +20°C and
+30°C after a
20 minute warmup period.
TABLE
1-1
ELECTRICAL CHARACTERISTICS
Characteristic Performance
Requirement
Supplemental Information
Deflection Factor
Single Ended Mode Less
than four volts/division
Differential Mode Less
than ten volts/division
Bandwidth 20 kilohertz
to one gigahertz
Maximum Input Power Six watts average;
200 volts DC
(Each Input)
Input Impedance
50 ohms, AC coupled
(Each Input)
Reflection Coefficient 0.1 peak-to-peak Using a reflectometer with a system
risetime
of 75 ps.
CIRCUIT DESCRIPTION
The 7A21 N circuitry is explained first as internally
connected for the differential mode of operation, then as
internally connected for
the single-ended mode of opera-
tion. It should be noted that the entire signal line is
designed to maintain a constant impedance of 50 Q.
The signal connected to the -INPUT is AC coupled
through C18 and inverted
in L21. The signal is inverted to
provide proper phasing with the +INPUT signal. After
inversion,
the signal is algebraically added to the +INPUT
signal
in the 50 Q Bridge, U12. The characteristics of this
bridge are such
that each input is terminated into 50 Q and
the output of the bridge has a source impedance of 50 Q.
The signal connected to the +INPUT is AC coupled
through C5,
then connected to U12 through the delay line,
L6. The delay time
of L6 is calculated so that the transit
time from the +INPUT connector to U12 is the same as the
transit time from the -INPUT connector to U12.
The
output of the 50 Q Bridge assembly, U12, is
connected to the compensating network composed of R24,
C24, R25, C25, R26, and L26. This
network compensates
®
for the skin effect losses and line losses in U12 and the
cables.
Power divider U30 splits
the signal into two directions.
The characteristics
of the Power Divider are such that,
when properly terminated, the impedance looking into any
leg is 50 Q.
The output of U30 at J31 is inverted at L56. Com-
ponents R61, C61, R62, C62, R63, and L63 compensate
for skin
effect losses and line losses of the cables, the
Inverter, and the Power Divider. The signal is then
capacitively coupled to the CRT deflection plate. The
output of U30 at J30 is connected to the delay line L36.
Delay
time for L36 is calculated so that the transit times of
the inverted and non-inverted signals are equal. R41, C41,
R42, C42, R43, and L43 compensate for
the skin effect
losses and line losses of the cables, delay line and Power
Divider. The non-inverted signal
is connected to the CRT
Input Network where it
is capacitively coupled to the CRT
vertical deflection plate. The
69 Q resistors on the CRT
Input Network parallel
the 182.5 Q impedance of the
deflection plates to form 50 Q term ination for the inverted
and non-inverted signals.
5

Single ended circuitry is similar to differential circuitry
except that the -INPUT
is not used and the signal at the
+INPUT bypasses 50
a Bridge U12 and the compensation
network R24, C24, R25, C25, R26, and L26.
The vertical deflection plates are terminated into their
characteristic impedance by the CRT Termination
Assembly, U120. Positioning voltage
is supplied from R96.
R98
sets the nominal position voltage. This control also has
an effect on the CRT trace focus.
The Load Board (located on U110) provides a storage
space for the power line that was removed from the
Oscilloscope Vertical Amplifier board. The +50 V and -15
V supplies in the power line are loaded so'that the supplies
stay in regulation during direct access operation. Proper
bias is supplied from the Load Board to protect the
oscilloscopeChannel Switch.
MAINTENANCE
General
Before replacing any component first note the physical
position of the component. Install the replacement part in
This portion of the manual contains information con-
cerning preventive maintenance, corrective maintenance the same position.
and troubleshooting the 7A21N.
Cleaning Corrective Maintenance
To improve reliability and to avoid possible electrical Standard Replacement Parts. All electrical and
problems, it is recommended that the 7A21N be cleaned at mechanical replacement parts for the 7A21N can be
obtained through your local field office or representative.
periodic intervals. However, many of the electronic parts can be obtained
locallv in less time than
is required to order them from
Loose dust may be removed with a soft cloth or a dry Tektronix, Inc. Before purchasing or ordering replacement
brush, Hardened dirt can be removed with a cotton-tipped
parts. check the parts list for value, rating, tolerance, and
swab or cloth, dampened with a mild detergent and water
description'
solution, then carefully rinsedand dried
Special Parts. In addition to the standard electronic
NOTE
components, some special parts are used in the 7A21N.
These parts are manufacturedor selected by Tektronix, Inc.
Calibration of the
7A21N can be effected if the in accordance with our specifications. These special parts
physical position of the components are moved, are indicated in the parts list by an asterisk preceding the
part number. Order all special parts directly from your local
TEKTRONIX FieldOffice or representative.
Troubleshooting
If trouble is suspected, before moving or replacing any Ordering Parts. When ordering replacement parts from
components, check that all cables and interconnections are Tektronix, Inc., include the instrument type, instrument
properly made. Refer to the Operating Instructions portion serial number, adescription of the part (if electrical include
of this manual for complete information. If trouble is still circuit number), and the TEKTRONIX part number.
evident and if calibration does not correct the problem,
then acomponent malfunction is the likely cause.
Soldering Techniques. Care should be taken when
Since the 7A21N contains no active components, all that soldering to prevent damage due to excess heat.
A small
is usually required to locate the defective part is an wattage soldering iron (15 to 50 watts) should be used.
ohmmeter. A reflectometer (such as the TEKTRONIX Apply heat directly to the junction to be soldered. Use only
7L12 or 1501) can be used to pinpoint the problem area by enough heat to form a good bond. Heat sink components
checking for discontinuities in the 50 signal path. when necessary.
8
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7A21N
Single ended circuitry is similar to differential circuitry
except that the -INPUT is not used and the signal at the
+INPUT bypasses 50 n Bridge U12 and the compensation
network R24, C24, R25, C25, R26, and L26.
The vertical deflection plates are terminated into their
characteristic impedance by the CRT Termination
Assembly, U120. Positioning voltage is supplied from R96.
R98 sets the nominal position voltage. This control also has
an
effect on the CRT trace focus.
The Load Board (located on U110) provides a storage
space for
the power line that was removed from the
Oscilloscope Vertical Amplifier board. The +50 V and -15
V supplies in the power line are loaded so"that the supplies
stay in regulation during direct access operation. Proper
bias is supplied from the Load Board to protect the
oscilloscope Channel Switch.
MAINTENANCE
General
This portion of the manual contains information con-
cerning preventive
maintenance, corrective maintenance
and troubleshooting the 7A21 N.
Cleaning
To improve reliability and to avoid possible electrical
problems, it is recommended that the 7A21 N be cleaned at
periodic intervals.
Loose
dust may be rem oved with a soft cloth or a dry
brush. Hardened dirt can be removed with a cotton-tipped
swab or cloth, dampened with a mild detergent and water
solution, then carefully rinsed and dried.
NOTE
Calibration of the lA21N can be effected if the
phvsical position of the components are moved.
Troubleshooting
If trouble is suspected, before moving or replacing any
components, check that all cables and interconnections are
properly made. Refer to the Operating Instructions portion
of this manual for complete information. If trouble is still
evident and if calibration does not correct the problem,
then a component malfunction is the likely cause.
Since
the 7A21 N contains no active components, all that
is usually required to locate the defective part is an
ohmmeter. A reflectometer (such as the TEKTRON IX
7L12 or 1501) can be used to pinpoint the problem area by
checking for
discontinuities in the 50 n signal path.
6
Before replacing any component first note the physical
position
of the component. Install the replacement part in
the same position.
Corrective Maintenance
Standard Replacement Parts. All electrical and
mechanical
replacement parts for the 7A21 N can be
obtained through your local field office or representative.
However,
many of the electronic parts can be obtained
locally in less time than is required to order them from
Tektronix, Inc. Before purchasing or ordering replacement
parts, check the parts list for value, rating, tolerance, and
description.
Special Parts. In addition to the standard electronic
components, some special parts are used in the 7A21 N.
These parts are manufactured or selected by Tektronix, Inc.
in accordance with our specifications. These special parts
are indicated
in the parts list by an asterisk preceding the
part number. Order all special parts directly from your local
TEKTRONIX Field Office or representative.
Ordering Parts. When ordering
replacement parts from
Tektronix, Inc., include the instrument type, instrument
serial number, a description of the part (if electrical include
circuit number), and the TEKTRON IX part number.
Soldering Techniques. Care should be taken when
soldering
to prevent damage due to excess heat. A small
wattage soldering iron (15
to 50 watts) should be used.
Apply
heat directly to the junction to be soldered. Use only
enough heat to form a good bond. Heat sink components
when necessary.
®
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CALIBRATION
Adjustment Procedure
NOTE
Two methods of setting the 7A21N Vertical Voltage
adjustment follow. If a focused trace was obtained prior to
the installation procedure, use Method A. An alternative
adjustment procedure is given as Method
B.
Method A:
1. Position the trace to the center of the CRT graticule
area with the 7A21N POSITION control.
2. Adjust Vertical Voltage adjustment, R98 (located on
left side of 7A21N) for awell-defined trace.
Method
B:
1. Position the trace to the center of the CRT graticule
area with the 7A21N POSITION control.
2. Measure and record the DC voltage between pin 10 of
the cathode ray tube and ground. Use a VOM set to the
50 V range, or higher, for this purpose.
Pin
70 of theCRT connects to the shield surrounding
the Vertical Deflection plates. The easiest place to
measure the voltage of this shield is on the multi-pin
connector connecting pin
70 of the CRT to the
Z
Axis Amplifier board. Refer to the oscilloscope
mainframemanual for the exact location.
3. Measure the DC voltage between each of the two
Vertical deflection platesand ground. Average these two
answers by the formula:
4. Adjust the Vertical Voltage adjustment, R98 so that
the voltage measured at pin 10 of the CRT (step
2) and
the Vaverage(calculated from step 3) are within 0.5
volt.
This completes the adjustment for the 7A21N.
PERFORMANCE CHECK
General
The performance of this instrument can be checked
without making any internal adjustments by using the
following procedure. This procedure checks the instrument
against tolerances listed in the Specification section of this
manual. If the instrument does not meet any or all of these
specifications it is due to a malfunction. Refer to the
Troubleshooting portion of this manual for possible causes
and corrective techniques.
Test Equipment Required
General. The following test equipment and accessories,
or its equivalent, is required for a complete check of the
7A21N. Specifications given for the test equipment are the
minimum necessary for an accurate check. Therefore, the
specifications of any test equipment used must meet or
exceed the listed specifications. All
test equipment is
assumed to be correctly calibrated and operating within the
listed specifications. Detailed operating instructions for the
test equipment are not given in this procedure. Refer to the
instruction manual for the
test equipment if more informa-
tion
is needed.
Special Calibration Fixtures. Special TEKTRONIX test
fixtures are used in this procedure only where they
facilitate the PerformanceCheck. These special
test fixtures
are available from Tektronix, Inc. Order by part number
through your local TEKTRONIX Field Office or repre-
sentative.
Test Equipment Alternatives. All of the listed
test
equipment is required to completely check this instrument.
The PerformanceCheck procedure
is based on the first item
of equipment given as an example of applicable equipment.
When other equipment is substituted, control settings or
test setup may need to be altered slightly to meet the
requirements of the substitute equipment. If the exact item
of test equipment given as an example in the Test
Equipment list
is not available, first check the Specifica-
tions column carefully to see if any other equipment
is
available which might suffice. Then check the Usage
column to
see what this item of test equipment is used for.
If used for a check which is of little or no importance to
your measurement requirements, the item and correspond-
ing step(s)can be deleted.
7
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7A21N
CALIBRATION
Adjustment Procedure
Two methods of setting the 7A21 N Vertical Voltage
adjustment follow. If a focused trace was obtained prior to
the installation procedure, use Method A. An alternative
adjustment procedure is given as Method B.
Method A:
1. Position
the trace to the center of the CRT graticule
area with
the 7A21 N POSITION control.
2. Adjust Vertical Voltage adjustment, R98 (located on
left side
of 7A21N) for a well-defined trace.
Method B:
1. Position
the trace to the center of the CRT graticule
area with
the 7A21 N POSIT ION control.
2. Measure and record the DC voltage between pin 10 of
the cathode ray tube and ground. Use a VOM set to the
50 V range, or higher, for this purpose.
NOTE
Pin 10 of the CRT connects to the shield surrounding
the Vertical
Deflection plates. The easiest place to
measure the voltage
of this shield is on the multi-pin
connector connecting pin 10 of the CRT to the Z
Axis Amplifier board_ Refer to the oscilloscope
mainframe manual for the exact location.
3. Measure the DC voltage between each of the two
Vertical deflection plates and ground. Average these two
answers by the formula:
Vaverage
4. Adjust the Vertical Voltage adjustment, R98 so that
the voltage measured at pin 10 of the CRT (step 2) and
the Vaverage (calculated from step 3) are within 0.5
volt.
This
completes the adjustment for the 7A21 N.
PERFORMANCE CHECK
General
The performance of this instrument can be checked
without making any internal adjustments by using the
following procedure. This procedure checks the instrument
against tolerances listed in the Specification section of this
manual.
If the instrument does not meet any or all of these
specifications it
is due to a malfunction. Refer to the
Troubleshooting portion of this manual for possible causes
and corrective
techniques.
Test Equipment Required
General. The following test equipment and accessories,
or its equivalent, is required for a complete check of the
7A21 N. Specifications given for the test equipment are the
minimum necessary for an accurate check. Therefore, the
specifications of any test equipment used must meet or
exceed the listed specifications. All test equipment is
assumed to be correctly calibrated and operating within the
listed specifications. Detailed operating instructions for the
test equipment are not given in this procedure. Refer to the
instruction manual for the test equipment if more informa-
tion
is needed.
®
Special Calibration Fixtures. Special TEKTRONIX test
fixtures are used in this procedure only where they
facilitate the Performance Check. These special test fixtures
are available from
Tektronix, Inc. Order by part number
through your local TEKTRONIX Field Office or repre-
sentative.
Test Equipment Alternatives. All of the listed test
equipment is required to completely check this instrument.
The Performance Check procedure is based on the first item
of equipment given as an example of applicable equipment.
When other equipment is substituted, control settings or
test setup may need to be altered slightly to meet the
requirements of the substitute equipment. If the exact item
of test equipment given as an example in the Test
Equipment list is not available, first check the Specifica-
tions column carefully to see if any other equipment is
available which might suffice. Then check the Usage
column to see what this item of test equipment is used for.
If used for a check which is of little or no importance to
your measurement requirements, the item and correspond-
ing step(s) can be
deleted.
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TEST EQUIPMENT
Cables and Accessories
Description
1. Calibration
Oscilloscope
2. Time Base
Plug-in Unit
3. Test Oscilloscope
4. Time Domain
Reflectometer
5. Square-wave
Generator
6. Pulse Generator
7. Delay Line and
Trigger Pickoff
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MinimumSpecifications
T EKTRON
lX 7900-Series
7A21N system bandwidth to 1
GHz.
TEKTRONIX 76-Series time
base unit. 0.5 ns sweep rate
required.
Complete with time base unit
and vertical unit. Must have ver-
tical deflection factor of 5 V1
div.
System risetime, 75 ps; pulse
amplitude, 200 mV; input, single
ended; sensitivity, to 100mp.
Frequency, to 75 kHz; output
amplitude, 10 volts P-P into
50
a.
Pulse risetime, 250 ps or less;
pulse amplitude to 50 volts or
greater.
Delay time, approximately
75 ns; risetime, 175ps or less.
8. TEKTRONIX to
GRadapter
9. 20 ns Cable
10. GR Cable
(2each)
11. BNC Cable
12. SMA Male to
GR Adapter
Usage
Used throughout pro-
cedure to provide display.
Used throughout pro-
cedure to provide sweep.
Used for deflection factor
check.
Used tocheck input reflec-
tions and transit time.
Used to check Deflection
Factor.
Used to check risetime and
aberrations.
Used tocheck risetime and
aberrations.
TEKTRONIX female to GR
adapter.
Connectors, GR; impedance,
50
R; time delay, 20 ns.
Connectors, GR; impedance,
50
a; length, 20-inch.
Connectors, BNC; impedance,
50
a; length, 42-inch.
SMA (3mm)to GR adapter.
Examplesof Applicable
Test Equipment
a. TEKTRONIX 7904 oscillo-
scope with 7A21N installed.
a. TEKTRONIX 7692 Time
Base Unit.
a. TEKTRONIX 7603 Oscillo-
scope with TEKTRONIX
7A16A Vertical Unit and 7650
Time Base Unit or equivalent.
a. TEKTRONIX 7S12 TDRI
SAMPLER plug-in unit with
S-52 Pulse Generator head and
S-2 Sampling head. (Thissystem
to be used with the Test oscillo-
scope.)
a. TEKTRONIX 106 Square
Wave Generator.
a. TE
KTRONIX 109 Pulse
Generator.
a. TEKTRONIX 7M11 Delay
Line plug-inunit.
Used for transit time
check.
Used for risetime and aber-
ration checks and other
signal connections.
Used throughout proce-
dures for signal connec-
tions.
Used for external trigger in
the risetime and aberration
check.
Used for connections to
Time-Domain Reflecto-
meter pulse generator.
a. TEKTRONIX Part Number
017-0093-00.
a. TEKTRON
lX Part Number
017-0504-00.
a. TEKTRONIX Part Number
017-0515-00.
a. TEKTRONIX Part Number
012-0057-01.
a. TEKTRONIX Part Number
015-1007-00.
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7A21N
TEST EQUIPMENT
Examples of Applicable
Description
Minimum Specifications
Usage
Test Equipment
1. Calibration
TEKTRONIX
7900-Series Used
th roughout
pro-
a. TEKTRONIX
7904 oscillo-
Oscilloscope
7A21N system bandwidth to 1 cedure
to provide display. scope
with 7A21 N installed.
GHz.
2. Time Base
TEKTRONIX
7B-Series time Used throughout
pro- a.
TEKTRONIX
7B92 Time
Plug-in
Unit base unit.
0.5 ns
sweep rate cedure
to provide sweep.
Base Unit.
required.
3_ Test Oscilloscope Complete
with time
base unit
Used for deflection factor a. TEKTRONIX 7603 Oscillo-
and vertical
unit. Must have ver- check.
scope with
TEKTRONIX
tical deflection factor of 5 VI
7A16A Vertical Unit and 7B50
div.
Time Base Unit or equivalent.
4. Time Domain System risetime, 75 ps; pulse
Used to check input reflec- a. TEKTRON IX
7S12 TDRI
Reflectometer amplitude, 200 mV; input, single tions and transit time.
SAMPLER plug-in unit
with
ended; sensitivity, to 100 mp. S-52
Pulse Generator head and
S-2 Sampling head. (This system
to be used with the Test oscillo-
scope.)
5. Square-wave Frequency,
to
75 kHz; output Used to check Deflection a. TEKTRONIX
106 Square
Generator amplitude, 10 volts
Pop
into Factor.
Wave Generator.
50Q.
6. Pulse Generator
Pulse
risetime, 250 ps
or less; Used to check risetime and a. TEKTRONIX
109
Pulse
pulse amplitude
to 50 volts or aberrations. Generator.
greater.
7. Delay Line and
Delay time, a pproxim ately Used to check risetime and a. TEKTRONIX 7Mll Delay
Trigger
Pickoff 75 ns; risetime, 175 ps or less. aberrations. Line plug-in unit.
Cables and Accessories
8. TEKTRONIX to
TEKTRONIX
female
to
GR Used
for transit
time a. TEKTRON IX Part Number
GR adapter adapter. check. 017-0093-00.
9. 20 ns Cable
Co nnectors, GR;
impedance, Used for risetime and aber-
a. TEKTRONIX
Part Number
50
Q; time delay, 20 ns. ration checks and
other
017-0504-00.
signal connections.
10. GR Cable Connectors,
GR; impedance, Used throughout
proce- a. TEKTRONIX
Part Number
(2 each) 50
Q; length, 20-inch. dures for signal connec- 017-0515-00.
tions.
11. BNC Cable Connectors, BNC; impedance,
Used for external trigger in a. TEKTRONIX
Part Number
50
Q; length, 42-inch. the risetime and aberration 012-0057-01.
check.
12. SMA Male
to
SMA (3 mm) to GR adapter. Used for connections to a. TEKTRONIX Part Number
GR Adapter
Time-Domain
Reflecto- 015-1007-00.
meter pulse generator.
8 ®
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Preliminary Set Up
6. Vertically position the trace so that the pulse (now
negative going) starts at the graticule upper left side. Check
Connect the 7A21 internal connections for single- that the trace intersects the horizontal graticule centerline
ended operation. within
f 25 ps of the vertical line, see Fig. 6.
2. Install the 7A21N into the Calibration Oscilloscope 7. Disconnect Time-Domain Reflectometer. Reconnect
and turn power on. the cable to J29.
Alternate Procedure
Check Reflection Coefficient
Some reflectometers do not have a separate pulse
1. Connect the Time-Domain Reflectometer to the generator output and sampling input. If this
is the case,
7A21N +INPUT. Check that the reflections are 0.1 peak-to- disconnect the cable connected toJ29 and measure that the
peak or less (100mp peak-to-peakor less). reflected pulses at the +INPUT and -INPUT
is within 50 ps
of one another.
2. Change the 7A21N internal connections for differen-
tial operation.
3. Connect the Time-Domain Reflectometer to the
7A21N +INPUT. Check that the reflections are 0.1 peak-to-
peak or less (100mp peak-to-peakor less).
4. Connect the Time-Domain Reflectometer to the
7A21N -INPUT. Check that the reflections are 0.1
peak-to-peakor less (100 mp peak-to-peak).
Check +INPUT/-INPUT Transit Time
1. Remove the right side cover of the 7A21N. It is not
necessary to plug the 7A21N into the Calibration Oscillo-
scope for this check.
Fig. 5. +INPUT signal.
2. Remove the cable connected to J29 (on U30).
Connect the end of this cable to the Time-Domain
Reflectometer sampling head by using the TEKTRONIX to
GR adapter and GR Cable.
3. Connect the Time-Domain Reflectometer pulse
generator to the 7A21N +INPUT. Set the Reflectometer
TimeIDiv to 50 ps.
4. Use the Time-Domain Reflectometer controls to
obtain a full graticule display of the rising portion of the
pulse. Adjust the controls so that the pulse starts at the
lower left side of the graticule and intersects the graticule
center lines, see Fig. 5.
5. Without moving any controls, move the pulse
generator to the -INPUT.
Fig. 6. -INPUT signal.
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Prelim inary Set Up
1. Connect the 7A21 N internal connections for single·
ended operation.
2. Install the 7A21N into the Calibration Oscilloscope
and turn power on.
Check Reflection Coefficient
1. Connect the Time.-Domain Reflectometer to the
7A21 N +INPUT. Check that the reflections are 0.1 peak-to-
peak
or less (100 mp peak-to-peak or less).
2. Change
the 7A21 N internal connections for differen-
tial
operation.
3. Connect the Time-Domain Reflectometer to the
7A21 N +1 NPUT. Check that the reflections are 0.1 peak-to-
peak
or less (100 mp peak-to-peak or less).
4. Connect the Time-Domain Reflectometer to the
7A21 N -I NPUT. Check that the reflections are 0.1
peak-to-peak
or less (100 mp peak-to-peak).
Check +INPUT/-INPUT Transit Time
1. Remove the right side cover of the 7A21 N. It is not
necessary to plug the 7A21 N into the Calibration Oscillo-
scope for this check.
2. Remove
the cable connected to J29 (on U30).
Connect the end of this cable to the Time-Domain
Reflectometer sampling head by using the TEKTRON IX to
GR adapter and GR Cable.
3. Connect the Time-Domain Reflectometer pulse
generator
to the 7A21 N +INPUT. Set the Reflectometer
Time/Div to 50 ps.
4. Use the Time-Domain Reflectometer controls to
obtain a full graticule display of the rising portion of the
pulse. Adjust the controls so that the pulse starts at the
lower left side of the graticule and intersects the graticule
center lines, see Fig. 5.
5.
Without moving any controls, move the pulse
generator to the -INPUT.
®
7A21N
6. Vertically position the trace so that the pulse (now
negative going)
starts at the graticule upper left side. Check
that the trace intersects the horizontal graticule centerline
within
±25 ps of the vertical line, see Fig. 6.
7. Disconnect Time-Domain Reflectometer. Reconnect
the cable to J29.
Alternate Procedure
Some reflectometers do not have a separate pulse
generator
output and sampling input. If this is the case,
disconnect the cable connected to J29 and measure that the
reflected pulses at the +INPUT and -INPUT is within 50 ps
of one another_
Fig. 5. +INPUT signal.
Fig.
6. -INPUT signal.
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Check Deflection Factor
1. Install the 7A21N into the Calibration Oscilloscope.
2. Set the Square Wave Generator frequency control to
approximately 75 kHz. Use the
test Oscilloscope to adjust
the Square Wave Generator for an output of 10 volts
peak-to-peakinto 50
R.
3. Connect the Square Wave Generator to the 7A21N
+INPUT. Terminate the -INPUT into 50 R. Check for a
CRT display of at least 1division.
4. Connect the Square Wave Generator to the 7A21N
-INPUT. Terminate the +INPUT into 50 R. Check for a
CRT display of
at least 1division.
5. Change the 7A21N internal connections for single-
ended operation.
6. Connect the Square Wave Generator to the 7A21N
+INPUT. Terminate the -INPUT into 50 R. Check for a
CRT display of
at least 2.5 cm.
4. Check that the risetime of the display is less than
465
ps'.
5. Check that the aberrations are +4%, -6%, 8%
peak-to-peakor less.
6. Change the 7A21N internal connections to obtain
differential operation. Terminate the -INPUT into 50
R.
7. Connect the Pulse Generator to the 7A21N +INPUT
and adjust for
a 6 division display.
8. Check that the risetime of the display is less than
465 ps2.
9. Check that the aberrations are 10%peak-to-peakor
less.
10. Connect the Pulse Generator to the 7A21N
-INPUT. Terminate the +INPUT into 50
R.
11. Check that the risetime of the display is less than
465 ps'
.
Check Risetime and Aberration
1. Connect the Pulse Generator to obtain a pulse
duration of approximately 40 ns by connecting the 20 ns
GR cable between the two charge line outputs.
2. Connect the Pulse Generator output to the Delay
Line and Trigger Pickoff. Connectthe Delay Line output to
the 7A21N +INPUT. Connect the Trigger Pickoff to the
external trigger input of the Time Base unit.
3. Adjust the Pulse Generator to obtain a six-division
display. Set the triggering controls for
a stable display.
12. Check that the aberrations are 10%peak-to-peakor
less.
2~hisvalue was calculated from the formula where: TrpG is the
risetime of the pulse generator; TroL is the risetime of the delay
line; and Trsystem is the risetime of the
7A21N17904 system.
(TrpG)2 + (TrDL)2 + (Trsysteml2
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7A21N
Check Deflection Factor
1. Install the 7A21 N into the Calibration Oscilloscope.
2. Set
the Square Wave Generator frequency control to
approximately 75 kHz. Use the test Oscilloscope to adjust
the Square Wave Generator for an output of 10 volts
peak-to-peak into 50 st.
3. Connect the Square Wave Generator to the 7A21 N
+INPUT. Terminate
the -INPUT into 50 st. Check for a
CRT display of
at least 1 division.
4. Connect the Square Wave Generator to the 7A21 N
-INPUT. Terminate the +INPUT into 50 st. Check for a
CRT display of
at least 1 division.
5. Change
the 7A21 N internal connections for single-
ended
operation.
6. Connect the Square Wave Generator to the 7A21 N
+INPUT. Terminate
the -INPUT into 50 st. Check for a
CRT display
of at least 2.5 cm.
Check Risetime and Aberration
1. Connect the Pulse Generator to obtain a pulse
duration of approximately 40 ns by connecting the 20 ns
GR cable between
the two charge line outputs.
2. Connect the Pulse Generator output to the Delay
Line and Trigger Pickoff.
Connect the Delay Line output to
the 7A21 N +INPUT. Connect the Trigger Pickoff to the
external trigger input of the Time Base unit.
3. Adjust the Pulse Generator to obtain a six-division
display. Set
the triggering controls for a stable display.
10
4. Check that the risetime of the display is less than
465 pSl.
5. Check
that the aberrations are +4%, -6%, 8%
peak-to-peak or less.
6. Change
the 7A21 N internal connections to obtain
differential
operation. Terminate the -INPUT into 50 st.
7. Connect the Pulse Generator to the 7A21 N +INPUT
and adjust for a 6 division display.
8. Check that the risetime of the display is less than
465 pSl.
9. Check
that the aberrations are 10% peak-to-peak or
less.
10.
Connect the Pulse Generator to the 7A21 N
-INPUT. Terminate the +INPUT into 50 st.
11. Check that the risetime of the display is less than
465 pSl.
12. Check
that the aberrations are 10% peak-to-peak or
less.
2
This
value was calculated from the formula where: TrpG is the
risetime of the pulse generator; Tro L is the risetime of the delay
line; and Trsystem is the risetime of the 7A21N/7904 system.
Tr :y (Tr
pG
12 + (Tr
OL
I2 + (TrSysteml2
OR
Tr ;Y 2502 + 1752 + 350
2
®
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ELECTRICAL PARTS LIST
Replacement parts should be ordered from the Tektronix Field Office or Representative in your area.
Changes to Tektronix products give you the benefit of improved circuits and components. Please include
the instrument type number and serial number with each order for parts or service.
ABBREVIATIONS AND REFERENCE DESIGNATORS
AT
B
BT
C
Cer
CR
CRT
DL
DS
Elect.
EMC
EMT
F
Assembly, separable or
repairable
Attenuator, fixed or variable
Motor
Battery
Capacitor, fixed or variable
Ceramic
Diode, signal or rectifier
cathode-ray tube
Delay line
Indicating device (lamp)
Electrolytic
electrolytic, metal cased
electrolytic, metal tubular
Fuse
P
PMC
PT
Filter
Heat dissipating device
(heat sink, etc.
I
Heater
Connector, stationary portion
Relay
Inductor, fixed or variable
Inductor/resistor combination
Meter
Transistor or silicon-
controlled rectifier
Connector, movable portion
Paper, metal cased
paper, tubular
PTM
v
Var
VR
paper or plastic, tubular
molded
Resistor, fixed or variable
Thermistor
Switch
Transformer
Test point
Assembly, inseparable or
non-repairable
Electron tube
Variable
Voltage regulator (zener diode,
etc.
1
wire-wound
Crystal
Tektronix SerialIModel No.
Ckt. No. Part No.
Eff Disc Description
ASSEMBLY
670-2207-00
CAPACITORS
C5
C18
C24
C25
C41
C42
C61
C62
CONNECTORS
Jl,J3 017-0093-01
J 5 131-1003-00
J 6 131-1003-00
57 131-1003-00
J8 1
131-1003-00
JIOl
Jill
512
514,516
518
520
524
527
'~urnished as a unit with U30
MAIN Circuit Board Assembly
2.2 uF, Cer, 100
V, 20%
2.2 pF, Cer, 100
V, 20%
270 pF, Cer, 500
V,
5%
270 pF,
Cer, 500 V,
5%
270 pF, Cer, 500
V, 5%
270 pF, Cer, 500
V,
5%
270 pF,
Cer, 500 V,
5%
270 pF, Cer, 500
V,
5%
Adapter, GR to Tek connector
Receptacle, coaxial cable
Receptacle, coaxial cable
Receptacle, coaxial cable
Recepatcle, coaxial cable
Adapter, GR to Tek connector
Receptacle, coaxial cable
Receptacle, coaxial cable
Receptacle, coaxial cable
Recepatcle, coaxial cable
11
Scans bv OuCsource-Qotwns =>
Scans by ArtekMedia © 2007
ELECTRICAL PARTS LIST
Replacement parts should be ordered from the Tektronix Field Office or Representative in your area.
Changes to Tektronix products give you the benefit of improved circuits and components. Please include
the instrument type number and serial number with each order for parts or service.
ABBREVIATIONS AND
REFERENCE DESIGNATORS
A Assembly,
separable or
FL Filter PTM
paper or plastic, tubular
repairable
H Heat dissipating device molded
AT Attenuator, fixed or variable (heat sink, etc.)
R Resistor,
fixed or variable
B Motor HR Heater RT
Thermistor
BT Battery
J
Connector, stationary portion
S Switch
C
Capacitor, fixed or variable
K Relay T
Transformer
Cer Ceramic
L Inductor, fixed or variable TP
Test point
CR Diode, signal or rectifier LR
Inductor/resistor combination U Assembly,
inseparable or
CRT cathode-ray tube
M Meter
non-repairable
DL
Delay line Q Transistor or silicon- V Electron tube
DS Indicating device
(lamp)
controlled rectifier Var Variable
7A21N
Elect. Electrolytic P
Connector, movable
portion
VR
Voltage regulator
(zener diode,
EMC electrolytic, metal
cased
PMC Paper, metal cased
etc.)
EMT
electrolytic, metal tubular PT paper, tubular
WW
wire-wound
F Fuse Y Crystal
Tektronix Serial/Model
No.
Ckt. No. Part No.
Eff
Disc Description
ASSEMBLY
670-2207-00
MAIN Circuit Board Assembly
CAPACITORS
G5 283-0278-00
2.2
).IF, Ger, 100 V, 20%
G18
283-0278-00
2.2 ).IF,
Ger,
100 V, 20%
G24 283-0047-00
270 pF,
Ger,
500 V,
5%
G25 283-0047-00
270 pF,
Ger, 500 V, 5%
G41
283-0047-00 270
pF,
Ger,
500 V,
5%
G42
283-0047-00
270
pF, Ger, 500 v, 5%
G61 283-0047-00
270 pF,
Ger,
500 V, 5%
G62
283-0047-00 270
pF,
Ger,
500 V, 5%
CONNECTORS
J1,J3 017-0093-01
Adapter, GR
to Tek connector
J5
131-1003-00
Receptacle, coaxial cable
J6
131-1003-00
Receptacle, coaxial cable
J7
131-1003-00
Receptacle, coaxial cable
J8
131-1003-00
Recepatc1e, coaxial
cable
J10
1
J11
1
J12
1
J14,J16 017-0093-01
Adapter, GR to Tek connector
J18 131-1003-00
Receptacle, coaxial cable
J20
131-1003-00
Receptacle, coaxial
cable
J24
131-1003-00
Receptacle, coaxial
cable
J27
131-1003-00
Recepatc1e, coaxial
cable
1Furnished as a unit with U30
11
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Electrical Parts List-7A21 N
ELECTRICAL PARTS LIST (cont)
Tektronix SerialIModel No.
Ckt. No.
Part No. Eff Disc Description
CONNECTORS (cont )
1
J2g1
J301
531
, 533 131-1003-00
535 131-1003-00
537 131-1003-00
539 131-1003-00
INDUCTORS
L6 119-0370-00
L21 119-0397-00
L26 108-0182-00
L36 119-0370-00
L4 3 108-0182-00
L56 119-0369-00
L63 108-0182-00
Receptacle, coaxial cable
Receptacle, coaxial cable
Receptacle, caoxial cable
Receptacle, coaxial cable
Receptacle, coaxial cable
Receptacle, coaxial cable
Receptacle, coaxial cable
Receptacle, coaxial cable
Receptacle, coaxial cable
Receptacle, coaxial cable
Balun, 50
n, normalizer
Balun, 50
n, inverter (input)
0.3
pH
Balun, 50 R, normalizer
0.3
pH
Balun, 50 R, inverter
0.3
pH
RESIST9RS
U12 307-0397-00 Resistor, thick film, 50 n, bridge
~24 307-0023-00 4.7 n, 112 w, 10%
~25 307-0023-00 4.7 n, 1/2 w, 10%
R26 315-0431-00 BOlOlOO B010160 430 R, 1/4 W, 5%
~26~ 315-0271-00 ~010161 270 n, 1/4 w, 5%
U30 307-0378-00 Resistor, thick film, power divider
307-0059-00
BOlOlOO B010160
307-0056-00 B010161
307-0059-00 BOlOlOO B010160
307-0056-00 B010161
315-0431-00 BOlOlOO B010160
315-0301-00 B010161
307-0059-00 BOlOlOO B010160
307-0056-00 B010161
307-0059-00 BOlOlOO B010160
307-0056-00 B010161
315-0431-00 BOlOlOO B010161
315-0301-00 B010161
315-0222-00
311-1473-00
311-0978-00
'Furnished as a unit with U30
2~urnishedas a unit with 510, 511, & 512.
3~urnishedas a unit with 529, 530, & 531.
6.2
n, 1/2 w, 5%
4.3
n, 112 w, 5%
6.2 0, 1/2
W, 5%
4.3
n, 112 w, 5%
430
R, 1/4 W, 5%
300
R, 1/4 W, 5%
2.2
W2, 1/4 W, 5%
2 x 5
W2, Var
250
52, Var
Scans bp Outsource-Outwns =>
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Electrical Parts List-7 A21N
ELECTRICAL PARTS LIST (cont)
Ckt. No.
CONNECTORS
J29
1
J30
1
J31l
J33
J35
J37
J39
J41
J53
J55
J57
J59
J61
INDUCTORS
L6
L21
L26
L36
L43
L56
L63
RESIST9RS
U12
R24
R25
R26
R26
3
U30
R41
R41
R42
R42
R43
R43
R61
R61
R62
R62
R63
R63
R95
R96
R99
(cont)
Tektronix
Part No.
131-1003-00
131-1003-00
131-1003-00
131-1003-00
131-1003-00
131-1003-00
131-1003-00
131-1003-00
131-1003-00
131-1003-00
119-0370-00
119-0397-00
108-0182-00
119-0370-00
108-0182-00
119-0369-00
108-0182-00
307-0397-00
307-0023-00
307-0023-00
Serial/Model No.
Eff Disc
315-0431-00 B010100 B010160
315-0271-00 B010161
307-0378-00
307-0059-00 B010100 B010160
307-0056-00 B010161
307-0059-00 B010100 B010160
307-0056-00 B010161
315-0431-00 B010100 B010160
315-0301-00 B010161
307-0059-00 B010100 B010160
307-0056-00 B010161
307-0059-00 B010100 B010160
307-0056-00 B010161
315-0431-00 B010100 B010161
315-0301-00 B010161
315-0222-00
311-1473-00
311-0978-00
1
2Furnished as a unit with U30
3Furnished as a unit with J10, J11, & J12.
Furnished as a unit with J29, J30, & J31.
12
Description
Receptacle,
Receptacle,
Receptacle,
Receptacle,
coaxial cable
coaxial cable
caoxia1 cable
coaxial cable
Receptacle,
Receptacle,
Receptacle,
Receptacle,
Receptacle,
Receptacle,
coaxial cable
coaxial cable
coaxial cable
coaxial cable
coaxial cable
coaxial cable
Balun, 50 n, normalizer
Balun, 50 n, inverter (input)
0.3 IlH
Balun, 50 n, normalizer
0.3 IlH
Balun, 50 n, inverter
0.3 IlH
Resistor, thick film, 50 n, bridge
4.7 n, 1/2 W, 10%
4.7 n, 1/2 W, 10%
430 n, 1/4 W, 5%
270 n, 1/4 W, 5%
Resistor, thick film, power divider
6.2
n,
1/2 W,
5%
4.3 n, 1/2 W,
5%
6.2 n,
1/2 W,
5%
4.3 n, 1/2 W, 5%
430 n, 1/4 W,
5%
300 n, 1/4 W,
5%
6.2 n, 1/2 W, 5%
4.3 n, 1/2 W, 5%
6.2 n, 1/2 W, 5%
4.3 n, 1/2 W, 5%
430 n, 1/4 W, 5%
300 n, 1/4 W, 5%
2.2 kn, 1/4 W, 5%
2 x 5 kn, Var
250 n, Var
Scans by OutsouTce-Options =>

C5
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Scans by ArtekMedia © 2007
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