Tektronix 7L5 User manual

-
-
COI\I\MITTED TO EXCELLENCE
WARNING
THE FOLLOWING SERVICING INSTRUCTIONS ARE
FOR USE BY QUALIFIED PERSONNEL ONLY. TO
AVOID PERSONAL INJURY, DO NOT PERFORM ANY
SERVICING OTHER THAN THAT CONTAINED IN
OPERATING INSTRUCTIONS UNLESS YOU ARE
QUALIFIED TO DO SO.
Tektronix, Inc.
P.O. Box 500
Beaverton, Oregon 97077
070·2 1 84 -01
7L5
SPECTRUM
ANALYZER
SERVICE
INSTRUCTION MANUAL
Serial Number _____ _
Flnl Pr I nting NOV 1 976
ScflIU Iw O"I3oUI'U-l)pdoIfS ".>
Scans by ArtekMedia © 2008…..A.K.A….
-
-
COMMITTED TO EXCELLENCE
WARNING
THE FOLLOWING SERVICING INSTRUCTIONS ARE
FOR USE BY QUALIFIED PERSONNEL ONLY.
TO
AVOID PERSONAL INJURY, DO NOT PERFORM ANY
SERVICING OTHER
THAN THAT CONTAINED IN
OPERATING INSTRUCTIONS UNLESS YOU ARE
QUALIFIED
TO DO SO.
Tektronix, Inc.
P.O. Box 500
Beaverton, Oregon 97077
070 ·2 18 4 - 01
7L5
SPECTRUM
ANALYZER
SERVICE
INSTRUCTION MANUAL
Serial Number _____ _
Flnl Pr i nting NOV 1976
SnlU by OIlDoMrc e-Opd OIfS :z>

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WARRANTY
Tektr onix warrants that this product is freefrorn defects in materials
and workmanship. The
warranty period is one (1) year from the dale
of s hipment. Te ktr onix will. at its option, repair or rep lace th e
produc t if Tektronix determines it is defective with in the warranty
period and if it is return ed, freight prepaid , to a service center
designated by Tektronix .
Tektr onix is not obl igated to fur nish service u nder this warranty:
8. to repair damage resulting from attempts by personnel other
than Tektronix representatives to install, repair, or servicethe
product ;
b. to repair damage r esulting from imp r oper use or from
connecting the product to incompat ible equipment ~
c. if personnel other than Tektronix representatives modify the
hardw are or software.
There Is no impUed warranty ot Illness for a parllcular purpose .
Tektronix is not liable for consequential damages.
Copyright 10 1976, 1978Tektr onix ,IncoAil rights reserved.
Contents of this publication may not berepro duced in any
form without the written permission of Tekt ronix , Inc .
Products of Tektronix, Inc . and its subsidiaries are
covered by U.S. and fore
ign patents and/ or pending
patents.
TEKTRONIX, TEK, SCOP E-MOBILE , and ~ are reg-
istered trademarks of Tektronix. Inc. TELEQUIPMENT is
a registered trademark of Tektronix U.K. Lim ite d.
Printed in U.S.A. Speci
fication and price change
privileges are reserved.
ScIl/lS bp Olll$ource-Oplions =>
Scans by ArtekMedia © 2008…..A.K.A….
WARRANTY
Tek tronix warrants that th is product is fr ee from defects in ma terials
and
workmanship. T he warranty period is o ne (1) year from the da le
of sh ip ment. Tektr on ix will, at its option. repair or replace th e
product if Tektronix dete r mines it is defective with in the wa rr anty
period and if it is returned, freight prepaid. to a service center
designat ed by Tek tr on ix .
Tektronix is not obligat ed to furnish service under this warranty:
a. to repair damage r esulting from attempts by personnel other
tha n T ektro nix repr esentatives to instal l. re pair , or servicethe
product i
b. to repair damage resulting from Improper us r from
connecting the product to incompatible equipment ;
c. if personnel olher t han Tektr onix representa lives modify the
har dwa re or soft ware .
There i, no impUed warranty 01 Illness for 8 part ic ular purpose .
Tektronix Is not liable for consequential damages.
Copyright 01976, 1978 Tektronix, I nco Ali rights reserved.
Contentsol this publication may not be repr od uced in any
form without the written permission of Tektronix, Inc .
Pr
oducts of Tektronix , Inc . and its subsidia ries are
covered by U. S. and foreign patents and / or pending
patents .
T
EKT RON I X, TEK , SCO PE-MOB ILE, and '8 are reg -
ist
ered trademarks of Tektronix, In c. TELEQUI PME NT is
a
registered trademark of Tekt r onix U.K. Limi ted.
Printed in U.S.A. Specif i cation and price change
privileges are reserved.
Scans bp OIl/Sollrce-OpliolfS ->

7L5 Service
TABLE
OF
CONTENTS
Page Page
SECTION 1 GENERAL INFORMATION SECTION 4 CALIBRATION PROCEDURE
Introduction and Description
1-1 Complete or Partial Calibration 4-1
Manual Organization 1-2 History Information 4-1
Electrical Characteristics 1-2 Interaction
4-1
Frequency 1-2 Equipment Required 4-1
Input
1-3 Short Form Procedure and Record 4-2
Amplitude 1-3 Preliminary Procedure 4-3
Sweep 1-4 1. Check/Adjust the Reference
Output Connectors 1-4 Oscillator Frequency 4-6
Environmental Characteristics 1-5
2. Check/Adjust the Calibrator
Physical Characteristics 1-5
Output Level 4-6
Accessories and Options 1-5
3. Frequency Span/Div Calibration 4-7
Installation 1-5
4. Sweep Timing 4-9
Repackaging
for Shipment 1-6
5. 1st LO and 1st LO Phase Lock
Calibration 4-10
SECTION 2 CIRCUIT DESCRIPTION
6. Function IF Calibration 4-11
Block Diagrams
2-1
7. Calibrate the 250 kHz, 2nd
IF Processing Chain
2-1
Mixer, and 10.7 MHz Input Filter 4-12
Sweep Control and Frequency
8. Variable Resolution Calibration 4-13
Reference 2-2
9. Digital Storage Calibration
Frequency Control Circuits 2-3 (SN B069999 and below) 4-16
Readout 2-5 9A. Digital Storage Calibration
Display Processing 2-6 (SN B070000 and up) 4-18
Detailed
Circuit Description 2-7
Sweep Control 2-7 SECTION 5 MAINTENANCE
Trigger Logic and Sweep I
ntroduction
5-1
Control
2-11
Preventive Maintenance
Frequency Span and Readout 2-13
5-1
Tune Reference +N Loops 2-13 Cleaning
5-1
A&B Oscillator and Control 2-14 Lubrication 5-2
1st LO/1st LO Lock 2-15 Visual Inspection 5-2
Reference Level, Readout, and Transistor and Integrated
Timeslot 2-15
Circuit Checks 5-2
Readout and Timeslot Decode 2-18 Troubleshooting 5-2
IF Processing Chain 2-19 Troubleshooting Aids 5-2
Variable Resolution 2-20 Finding Faulty Semiconductors 5-3
10 kHz & 30 kHz Filters and General Troubleshooting
Post
VR Amplifier 2-22 Techniques 5-5
Corrective Maintenance 5-5
Log/Lin Amplifier 2-22 Disassembly
of the 7L5 and
Detector and Video Amplifier 2-22 Replacing Assemblies
Display Processing 2-23 5-7
Horizontal and Vertical Display Removing the Front Panel 5-7
Removing the IF Module
Processing 2-23 Assembly 5-7
Average Calculator (SN B069999 Removing the Sweep Board 5-8
and below) 2-24 Removing the
RF Module 5-9
Digital Storage (SN B069999 Reassembling the 7L5 5-9
and below) 2-25
Digital Storage and Averaging Internal Operational Adjustments 5-9
(SN B070oo0 and up) 2-30 SECTION 6 OPTION INFORMATION
SECTION 3 PERFORMANCE CHECK
Introduction
3-1
SECTION 7 REPLACEABLE ELECTRICAL
Equipment Required or
PARTS
Recommended 3-1
1. Sweep Triggering 3-2 SECTION 8 DIAGRAMS AND CIRCUIT
2. Dot Frequency Range and BOARD ILLUSTRATIONS
Accuracy 3-2
3. Display Flatness 3-3 SECTION 9 REPLACEABLE MECHANICAL
4. Frequency Span Accuracy & PARTS AND EXPLODED
Linearity 3-4 DRAWINGS
5. Sweep Rate Accuracy 3-5 CHANGEINFORMATION
6. Intermodulation Distortion 3-6
7. Display Frequency St!ibility 3-7
REV. A MAY 1978
Scans by ArtekMedia © 2008…..A.K.A….
7L5 Service
TABLE
OF
CONTENTS
Page Page
SECTION 1 GENERAL INFORMATION SECTION 4 CALIBRATION PROCEDURE
Introduction and Description
1-1 Complete or Partial Calibration 4-1
Manual Organization 1-2 History Information 4-1
Electrical Characteristics 1-2 Interaction
4-1
Frequency 1-2 Equipment Required 4-1
Input
1-3 Short Form Procedure and Record 4-2
Amplitude 1-3 Preliminary Procedure 4-3
Sweep 1-4
1. Check/Adjust the Reference
Output Connectors 1-4 Oscillator Frequency 4-6
Environmental Characteristics 1-5
2. Check/Adjust the Calibrator
Physical Characteristics 1-5
Output Level 4-6
Accessories and Options 1-5
3. Frequency Span/Div Calibration 4-7
Installation 1-5
4. Sweep Timing 4-9
Repackaging
for Shipment 1-6
5. 1st LO and 1st LO Phase Lock
Calibration 4-10
SECTION 2 CIRCUIT DESCRIPTION
6. Function IF Calibration 4-11
Block Diagrams
2-1
7. Calibrate the 250 kHz, 2nd
IF Processing Chain
2-1
Mixer, and 10.7 MHz Input Filter 4-12
Sweep Control and Frequency
8. Variable Resolution Calibration 4-13
Reference 2-2
9. Digital Storage Calibration
Frequency Control Circuits 2-3 (SN B069999 and below) 4-16
Readout 2-5 9A. Digital Storage Calibration
Display Processing 2-6 (SN B070000 and up) 4-18
Detailed
Circuit Description 2-7
Sweep Control 2-7 SECTION 5 MAINTENANCE
Trigger Logic and Sweep Introduction
5-1
Control
2-11
Preventive Maintenance
Frequency Span and Readout 2-13
5-1
Tune Reference +N Loops 2-13 Cleaning
5-1
A&B Oscillator and Control 2-14 Lubrication 5-2
1st LO/1st LO Lock 2-15 Visual Inspection 5-2
Reference Level, Readout, and Transistor and Integrated
Timeslot 2-15
Circuit Checks 5-2
Readout and Timeslot Decode 2-18 Troubleshooting 5-2
IF Processing Chain 2-19 Troubleshooting Aids 5-2
Variable Resolution 2-20 Finding Faulty Semiconductors 5-3
10 kHz & 30 kHz Filters and General Troubleshooting
Post
VR Amplifier 2-22 Techniques 5-5
Corrective Maintenance 5-5
Log/Lin Amplifier 2-22 Disassembly
of the 7L5 and
Detector and Video Amplifier 2-22 Replacing Assemblies
Display Processing 2-23 5-7
Horizontal and Vertical Display Removing the Front Panel 5-7
Removing the IF Module
Processing 2-23 Assembly 5-7
Average Calculator (SN B069999 Removing the Sweep Board 5-8
and below) 2-24 Removing the
RF Module 5-9
Digital Storage (SN B069999 Reassembling the 7L5 5-9
and below) 2-25
Digital Storage and Averaging Internal Operational Adjustments 5-9
(SN B070oo0 and up) 2-30 SECTION 6 OPTION INFORMATION
SECTION 3 PERFORMANCE CHECK
Introduction
3-1
SECTION 7 REPLACEABLE ELECTRICAL
Equipment Required
or
PARTS
Recommended
3-1
1. Sweep Triggering 3-2 SECTION 8 DIAGRAMS AND CIRCUIT
2. Dot Frequency Range and BOARD ILLUSTRATIONS
Accuracy 3-2
3. Display Flatness 3-3 SECTION 9 REPLACEABLE MECHANICAL
4. Frequency Span Accuracy & PARTS AND EXPLODED
Linearity 3-4 DRAWINGS
5. Sweep Rate Accuracy 3-5 CHANGEINFORMATION
6. Intermodulation Distortion 3-6
7. Display Frequency St!ibility 3-7
REV. A MAY 1978

"-
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--
So!
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I
...
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...
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173 4-1 A
Fig. 1-1. 7LS Spectrum An.'yzer,
I 7L5 Service
REV A, MAY 1 978
Sc allS by OlltsDllrce-()DlioIl S->
Scans by ArtekMedia © 2008…..A.K.A….
Fig. 1 -1 . 7LS Spectrum Analyter .
7L5 Service
.. -
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REV A, MAY 19 78
Sc.1U bp OM""UN:t-()pt;OIlS .,.

7L5 Service
GENERAL INFORMATION
INTRODUCTION AND DESCRIPTION
To effectively use the 7L5 Spectrum Analyzer, the
operation and capabilities of the instrument must
be
known. This instruction manual covers general service
information
for the instrument. It contains the specifica-
tion, test and calibration procedure,
circuit description,
and maintenance procedure
for the 7L5.
The 7L5
is a 5 MHz spectrum analyzer with digital
storage. Frequency stability is within 5 Hz/hr and center
frequency (dot) can be read with six
digit accuracy
immediately after turn-on; therefore there is no need to
fine tune the display. Complex measurements and
analysis can be made with relative ease. Built-in
microprocessingcircuitsdecodecontrol settings, process
frequency and reference level information, and optimize
sweep time and resolution for the selected frequency
span. At turn-on, the 7L5
is preset to a reference level of
+17 dBm (50 °input) and center frequency of 00.0 kHz:
This provides input attenuation to protect the front-end
circuitry and a marker to verify correct operation.
The 7L5 with 80
dB or more of spurious free dynam'ic
range provides the ability
to measure wide relative
amplitudes. Nanovolt sensitivity provides very low-level
signal and noise requirements.
The 7L5 display is
fully calibrated in dBm, dBV, or
volts/div. The reference level can beaccuratelyset in 1 dB
increments.
A
front panel input buffer control increases front-end
immunity to intermodulation distortion while maintaining
a constant reference level.
@
To accommodate a wide variety ofimpedancesources,
the 7L5 uses quick disconnect plug-in
input impedance
modules of 50 0, 75 0, 600 0, 1 MO/28 pF and customiz-
ed units to meet special requirements.
When the
7L5'sdigital storage capability is employed,
one or two complete displays can be held in memory for
subsequent viewing, comparison, or graphic reproduc-
tion. This capability converts a nonstorage, 7000-Series
oscilloscope display
into a stored display. The small dot
size (of the conventional oscilloscope) used with the 7L5
enhances the resolution of low amplitude signals and
other fine details that are often lost with a variable
persistence oscilloscope. In storage mode, the vertical
display may be bisected by
an averaging threshold, above
which video peak detection occurs (prior
to storage) and
below which video signal averaging occurs (prior to
storage). Denoted by a cursor, the averaging threshold is
continuously adjustable with a front panel control. The
storage
circuitry includes a maximum hold capability.
This feature allows monitoring of signals thatmaychange
with time
to provide a graphic record of amplitude/fre-
quency excursion.
WARNING I
The following service instructions are for personnel
qualified toservice electronic circuits. Personnel not
familiar with electrical circuit operation should not
perform any service other than that contained in the
Operating
Instuction manual.
1-1
Scans by ArtekMedia © 2008…..A.K.A….
7L5 Service
GENERAL INFORMATION
INTRODUCTION AND DESCRIPTION
To effectively use the 7L5 Spectrum Analyzer, the
operation and capabilities of the instrument must
be
known. This instruction manual covers general service
information
for the instrument. It contains the specifica-
tion, test and calibration procedure,
circuit description,
and maintenance procedure
for the 7L5.
The 7L5
is a 5 MHz spectrum analyzer with digital
storage. Frequency stability is within 5
Hz/hr and center
frequency (dot) can be read with six
digit accuracy
immediately after turn-on; therefore there
is no need to
fine tune the display. Complex measurements and
analysis can
be made with relative ease. Built-in
microprocessingcircuitsdecodecontrol settings, process
frequency and reference level information, and optimize
sweep time and resolution
for the selected frequency
span. At turn-on, the 7L5
is preset to a reference level of
+17 dBm (50 °input) and center frequency of 00.0 kHz:
This provides input attenuation to protect the front-end
circuitry and a marker to verify correct operation.
The 7L5 with 80
dB or more of spurious free dynam'ic
range provides the ability
to measure wide relative
amplitudes. Nanovolt sensitivity provides very low-level
signal and noise requirements.
The 7L5 display is
fully calibrated in dBm, dBV, or
volts/div. The reference level can beaccuratelyset in 1 dB
increments.
A
front panel input buffer control increases front-end
immunity to intermodulation distortion while maintaining
a constant reference level.
@
To accommodate a wide variety ofimpedancesources,
the 7L5 uses quick disconnect plug-in
input impedance
modules of 50 0, 75 0, 600 0, 1 MO/28 pF and customiz-
ed units to meet special requirements.
When the
7L5'sdigital storage capability is employed,
one
or two complete displays can be held in memory for
subsequent viewing, comparison, or graphic reproduc-
tion. This capability converts a nonstorage, 7000-Series
oscilloscope display
into a stored display. The small dot
size (of the conventional oscilloscope) used with the 7L5
enhances the resolution of low amplitude signals and
other fine details that are often lost with a variable
persistence oscilloscope. In storage mode, the vertical
display may be bisected by
an averaging threshold, above
which video peak detection occurs (prior
to storage) and
below which video signal averaging occurs
(prior to
storage). Denoted by a cursor, the averaging threshold is
continuously adjustable with a front panel control. The
storage
circuitry includes a maximum hold capability.
This feature allows monitoring of signals thatmaychange
with time
to provide a graphic record of amplitude/fre-
quency excursion.
WARNING I
The following service instructions are for personnel
qualified toservice electronic circuits. Personnel not
familiar with electrical circuit operation should not
perform any service other than that contained in the
Operating
Instuction manual.
1-1

General Information-7L5 Service
MANUAL ORGANIZATION AND
CONTENT
The abbreviations, graphic symbols, and logic sym-
bology used in the text and diagrams of this manual are in
accord with and based on ANSI Y1.1-1972, ANSI Y 32.3-
1975,
and ANSI Y32.14-1973 (American National Standard
Institute, 345 East 47 Street; New York, N.Y. 10017).
Change information is contained on insert pages at the
back of the manual. Original pages are identified by the
symbol @ and revised pages are identifed by a revision
date in the lower inside corner of the page. If the serial
number of your instrument is lower than the one on the
title page, the manual contains revisions that may not
apply to your instrument. History information, applicable
to previous products, with the updated data, is integrated
when the page or diagram is revised. The following
describes the sections and information provided in this
manual.
Section 1-General Information: Contains the instru-
ment description and specification.
Section 2-Circuit Description: Provides basic and
general circuit theory. This information may be useful
when servicing or operating the instrument.
Section 3-Performance Check: Procedures to verify
that the instrument is performing within its specified
limits.
Section 4-Calibration Procedure: Test equipment
setup and adjustment procedures required to calibrate the
instrument.
Section 5-Maintenance: Describes routine and cor-
rective maintenance procedures with detailed instructions
for replacing assemblies, sub-assemblies, or individual
components. An exploded drawing is part of Section 9.
Troubleshooting procedures plus general information
that may aid in servicing the instrument arealso provided.
Section 6-0ptions Information: Describes options to
the instrument or directs the reader to where the options
are documented.
Section 7-Replaceable Electrical Parts: Provides in-
formation necessary to order replaceable parts and
assemblies.
1-2
Section 8-Diagrams: Functional block diagrams and
detailed circuit schematics are provided. Located adja-
cent to the diagram (usually on the back of the preceding
diagram) are pictorial layout drawings that show sub-
assembly and component locations. Integrated circuit
diagrams, waveforms and voltage data for
troubleshooting or circuit analysis are also provided
adjacent to or on the diagram.
Section 9-Replaceable Mechanical Parts, Exploded
Drawings and Accessories: Provides information
necessary to order replaceable parts. The Replaceable
Parts list is cross-referenced to the Replaceable Electrical
Parts list. The exploded drawing identifies assembliesand
mechanical components.
Change Information: Provides updating information in
the form of inserts for the manual. These inserts are later
incorporated into the manual text and diagrams when the
manual is reprinted.
ELECTRICAL CHARACTERISTICS
The following electrical characterstics apply when the
7L5
Spectrum Analyzer, in combination with a Plug-In
Module, are normally installed in a 7000-Series os-
cilloscope and after a warm-up of ten minutes or more.
Frequency Characteristics
Range
Input Frequency: 10 Hz through 5.0 MHz.
Dot Frequency: 0 Hz through 4999.75 kHz.
Accuracy
20°C to 30°C: ±(5 Hz +2 X 10-6 of dot readout).
O°C to 50°C: ±(20 Hz + lO-
l
of dot readout).
Drift
5 Hz/hour or less.
Residual (Incidental) FM
50 Hz/div to 2 kHz/div: 1 Hz (p-p) or less.
5 kHz/div to 500 kHz/div: 40 Hz (p-p) or less.
@
Scans by Ollbollrce-Options =>
Scans by ArtekMedia © 2008…..A.K.A….
General Information-7L5 Service
MANUAL ORGANIZATION AND
CONTENT
The abbreviations, graphic symbols, and logic sym-
bology used in the text and diagrams of this manual are in
accord with and based on ANSI Y1.1-1972, ANSI Y 32.3-
1975,
and ANSI Y32.14-1973 (American National Standard
Institute, 345 East 47 Street; New York, N.Y. 10017).
Change information is contained on insert pages at the
back of the manual. Original pages are identified by the
symbol @ and revised pages are identifed by a revision
date in the lower inside corner of the page. If the serial
number of your instrument is lower than the one on the
title page, the manual contains revisions that may not
apply to your instrument. History information, applicable
to previous products, with the updated data, is integrated
when the page or diagram is revised. The following
describes the sections and information provided in this
manual.
Section 1-General Information: Contains the instru-
ment description and specification.
Section 2-Circuit Description: Provides basic and
general
circuit theory. This information may be useful
when servicing or operating the instrument.
Section 3-Performance Check: Procedures to verify
that the instrument is performing within its specified
limits.
Section 4-Calibration Procedure: Test equipment
setup and adjustment procedures required to calibrate the
instrument.
Section 5-Maintenance: Describes routine and cor-
rective maintenance procedures with detailed instructions
for replacing assemblies, sub-assemblies, or individual
components. An exploded drawing is part of Section 9.
Troubleshooting procedures plus general information
that may aid in servicing the instrument arealso provided.
Section 6-0ptions Information: Describes options to
the instrument or directs the reader to where the options
are documented.
Section 7-Replaceable Electrical Parts: Provides in-
formation necessary to order replaceable parts and
assemblies.
1-2
Section 8-Diagrams: Functional block diagrams and
detailed circuit schematics are provided. Located adja-
cent to the diagram (usually on the back of the preceding
diagram) are pictorial layout drawings that show sub-
assembly and component locations. Integrated circuit
diagrams, waveforms and voltage data for
troubleshooting or circuit analysis are also provided
adjacent to or on the diagram.
Section 9-Replaceable Mechanical Parts, Exploded
Drawings and Accessories: Provides information
necessary to order replaceable parts. The Replaceable
Parts
list is cross-referenced to the Replaceable Electrical
Parts list.
The exploded drawing identifies assembliesand
mechanical components.
Change Information: Provides updating information in
the form of inserts for the manual. These inserts are later
incorporated into the manual text and diagrams when the
manual is reprinted.
ELECTRICAL CHARACTERISTICS
The following electrical characterstics apply when the
7L5
Spectrum Analyzer, in combination with a Plug-In
Module, are normally installed in a 7000-Series os-
cilloscope and after a warm-up of ten minutes or more.
Frequency Characteristics
Range
Input Frequency: 10 Hz through 5.0 MHz.
Dot Frequency: 0 Hz through 4999.75 kHz.
Accuracy
20°C to 30°C: ±(5 Hz +2 X 10-6 of dot readout).
O°C
to 50°C: ±(20 Hz + lO-
l
of dot readout).
Drift
5 Hz/hour or less.
Residual (Incidental) FM
50 Hz/div to 2 kHz/div: 1 Hz (p-p) or less.
5
kHz/div to 500 kHz/div: 40 Hz (p-p) or less.
@
Scans by Ollbollrce-Options =>

Resolution Bandwidth
Accuracy
30 kHz-30 Hz: Within 20%ofselected resolution
(6 dB down).
10 Hz: Within 100 Hz ±20 Hz (70 dB down).
The COUPLED setting electronically selects
the best resolution bandwidth for each setting of
the FREQUENCY SPAN/DIV control.
Shape Factor
30 kHz-3 kHz: 5:1 or better (60:6 dB ratio).
1
kHz-10 Hz: 10:1 or better (60:6 dB ratio).
Amplitude Deviation
30 kHz-100 Hz: 0.5 dB or less.
30
kHz-10 Hz: 2.0 dB or less.
Input Characteristics
~
The application of a dc voltage to the INPUT of the
L1
or L2 Plug-In Modules may cause permanent
damage to the mixer circuit.
Input Impedance (Nominal):
L1 500
L2 750
L3 Selectable (50 0, 600 0, and 1 MO/28 pF).
Input Power (maximum input level for reference levels
of 0 dBm or greater):
L1
21 dBm or 2.5 V rms
L2
21 dBm or 3.07 V rms
L3
21 dBm-input terminated 50 0 or 6000;
100 V (peak ac + dc) input 1 MO/28 pF.
Input Power (maximum input level for reference levels
below 0 dBm):
L1 +10 dBm
L2 +10 dBm
L3 +10 dBm-input terminated 500 or 600 0,
and 100 V (peak ac + dc) with input of 1 MO/28 pF.
@
Generallnformation-7L5 Service
Amplitude Characteristics
NOTE
If digital storage is used, an additional quantization
error of 0.5% of full screen should be added to the
amplitude characteristics.
Residual Response
Internally generated spurious signalsare -130 dBm
or less referred to the input (harmonics of the calibrator
are -125 dBm) with L1 or L2 plug-in module and
-143 dBV with the L3 plug-in module.
Sensitivity
The following tabulation of equivalent input noise
for each resolution bandwidth is measured with; the
INPUT BUFFER off, the VIDEO PEAK/AVG at max cw,
and the TIME/DIV set to 10 seconds.
Equivalent Input Noise
Resolution (equal
to or better than)
Bandwidth
L1 L2 L3
10 Hz -135 dBm -135 dBm -148 dBV
30 Hz
-133 dBm -133 dBm -146 dBV
100 Hz
-130 dBm -130 dBm -143 dBV
300 Hz
-125 dBm -125 dBm
-138 dBV
1 kHz
-120 dBm
-120 dBm -133 dBV
3 kHz
-115 dBm -115 dBm -128 dBV
10 kHz
-110 dBm -110dBm -123 dBV
30 kHz
-105 dBm -105 dBm -118 dBV
NOTE
Sensitivity is degraded an additional 8 dB when the
INPUT BUFFER is on; e.g., at 3 kHz, the equivalent
input nOise would be -107 dBm instead of
-115 dBm. Noise level will increase by ap-
proximately 10 dB when operation is in video peak
mode.
Intermodulation Distortion
Intermodulation products from two on-screen
signals, within any frequency span are ?75 dB down
for third order products and at least 72 dB down for
second order products.
Second and third order intermodulation products
from two on-screen -53 dBV or less signals within any
frequency span are at least 80 dB down.
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Resolution Bandwidth
Accuracy
30 kHz-30 Hz: Within 20%ofselected resolution
(6 dB down).
10 Hz: Within 100 Hz ±20 Hz (70 dB down).
The COUPLED setting electronically selects
the best
resolution bandwidth for each setting of
the FREQUENCY SPAN/DIV control.
Shape Factor
30 kHz-3 kHz: 5:1 or better (60:6 dB ratio).
1
kHz-10 Hz: 10:1 or better (60:6 dB ratio).
Amplitude Deviation
30
kHz-100 Hz: 0.5 dB or less.
30
kHz-10 Hz: 2.0 dB or less.
Input Characteristics
~
The application of a dc voltage to the INPUT of the
L1
or L2 Plug-In Modules may cause permanent
damage to the mixer circuit.
Input Impedance (Nominal):
L1 500
L2 750
L3 Selectable (50 0, 600 0, and 1 MO/28 pF).
Input Power
(maximum input level for reference levels
of 0 dBm or greater):
L1
21 dBm or 2.5 V rms
L2
21 dBm or 3.07 V rms
L3
21 dBm-input terminated 50 0 or 6000;
100 V (peak ac + dc) input 1 MO/28 pF.
Input Power
(maximum input level for reference levels
below 0 dBm):
L1 +10 dBm
L2 +10 dBm
L3 +10 dBm-input terminated 500 or 600 0,
and 100 V (peak ac + dc) with input of 1 MO/28 pF.
@
Generallnformation-7L5 Service
Amplitude Characteristics
NOTE
If digital storage is used, an additional quantization
error of 0.5% of full screen should be added to the
amplitude characteristics.
Residual Response
Internally generated spurious signalsare -130 dBm
or less referred to the input (harmonics of the calibrator
are -125 dBm) with L1 or L2 plug-in module and
-143 dBV with the L3 plug-in module.
Sensitivity
The following tabulation of equivalent input noise
for each resolution bandwidth is measured with; the
INPUT BUFFER off, the VIDEO PEAK/AVG at max cw,
and
the TIME/DIV set to 10 seconds.
Equivalent Input Noise
Resolution (equal
to or better than)
Bandwidth
L1 L2 L3
10 Hz -135 dBm -135 dBm -148 dBV
30 Hz
-133 dBm -133 dBm -146 dBV
100 Hz
-130 dBm -130 dBm -143 dBV
300 Hz
-125 dBm -125 dBm
-138 dBV
1 kHz
-120 dBm
-120 dBm -133 dBV
3 kHz
-115 dBm -115 dBm -128 dBV
10 kHz
-110 dBm -110dBm -123 dBV
30 kHz
-105 dBm -105 dBm -118 dBV
NOTE
Sensitivity is degraded an additional 8 dB when the
INPUT BUFFER is on; e.g., at 3 kHz, the equivalent
input nOise would be -107 dBm instead of
-115 dBm. Noise level will increase by ap-
proximately 10 dB when operation is in video peak
mode.
Intermodulation Distortion
Intermodulation products from two on-screen
signals, within any frequency span are ?75 dB down
for third order products and at least 72 dB down for
second order products.
Second and third order intermodulation products
from two on-screen -53 dBV or less signals within any
frequency span are at least 80 dB down.
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General Information-7L5 Service
With the INPUT BUFFER switch on, the third order
intermodulation products, for any two on-screen
signals, within any frequency span, are at least 80 dB
down.
Display Flatness
Peak to peak deviation, over any selected frequency
span: Quantization error must be added (see Note under
Amplitude Characteristics) if digital storage is used.
L1
L2
L3
0.5 dB;
0.5 dB;
0.5 dB;
Reference Level
Refers to top graticule line in Log mode. Calibrated in
1
dB and 10 dB steps for the L1 and L2 modules and
1 dB/2 dB and 10 dB for L3 plug-in module.
Range L1
L2 L3
Log
-128 dBm
-128 dBm/
-128 dBm to
2 dB/Div to +21 dBm
139 dBV to
+21 dBm (50 0),
+21 dBm/
-139 dBm to
+10 dBV
+10dBm(600 0),
-141 dBV to
+8 dBV (Hi Z)
Log
-70 dBm
-70 dBm/
-70 dBm to
10 dB/Div to +21 dBm
-81 dBV to +21 dBm (50 0),
+21 dBm/
-81 dBm to
+10 dBV
+10dBm (6000),
-83 dBV to
+8 dBV (Hi Z)
Incremental Accuracy
When calibrated at -40 dBV in Log mode:
L
1, L2 and L3: Within0.2 dB/dB with cumulative errorof
0.25 dB/10 dB.
Lin Mode Range:
20 mV/Div to 200 mV/Divwithin 5%in
1-2-5 sequence.
NOTE
A >sign is displayed adjacent to the reference level
readout when the reference level is not calibrated
due to an incompatible selection of controls.
Display Dynamic Range/Accuracy
Log 10 dB/Div Mode: Dynamic window is 80 dB.
Accuracy is within 0.05 dB/dB to 2 dB maximum.
Log 2
dB/Div Mode: Dynamic window is 16 dB. Ac-
curacy is within 0.1 dB/dB to 1 dB maximum.
1-4
Sweep Characteristics
Frequency Span. Provides calibrated frequency spans
from 50 Hz/div to maximum 500 kHz/div, within 4%, in 1-2-
5 sequence.
Horizontal linearity is within 4% over the entire 10 div
display.
A O-Hz/Div position is provided for time domain
operation.
Sweep Rate. Time per div is selectable from 10 s/div to
0.1 ms/div in a 1-2-5sequence. An AUTO position permits
automatic selection of
optimum time/div for the selected
resolution and span/div.
Sweep rate accuracy is within 5% of the rate selected.
Triggering. Provides two triggering sources, INT (inter-
nal) and LINE, in addition to a FREE-RUN position.
When
INT is selected, ac coupled signal components
from the mainframe Trigger Source (left or right vertical
amplifiers) are used.
When LINE is selected, ac
coupled sample of main-
frame line voltage is used.
Three
triggering modes are; NORM (normal), SGL
SWP/READY (single sweep), and MNL SWEEP (manual
sweep).
Trigger level is ~1.0 div of internal signal for both
NORM and SGL SWP modes over the approximate
frequency range of 30 Hz to 500 kHz.
Output Connectors
Video Out. Front-panel pin jack connector suppliesthe
video (vertical)
output signal at an amplitude of 50 mV/div
±5% (about the crt vertical center) with source impedance
of 1 kO.
Horiz Out. A front-panel pin jack connector supplies
horizontal
output signal (negative-going sawtooth that
varies from 0.0 V
dc to approximately -6 V dc) with a
source impedance of 5
kO.
REV. A MAY 1978
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General Information-7L5 Service
With the INPUT BUFFER switch on, the third order
intermodulation products, for any two on-screen
signals,
within any frequency span, are at least 80 dB
down.
Display Flatness
Peak
to peak deviation, over any selected frequency
span: Quantization error must be added (see Note under
Amplitude Characteristics) if digital storage is used.
L1
L2
L3
0.5 dB;
0.5 dB;
0.5 dB;
Reference Level
Refers to top
graticule line in Log mode. Calibrated in
1
dB and 10 dB steps for the L1 and L2 modules and
1 dB/2 dB and 10 dB for L3 plug-in module.
Range
L1
L2 L3
Log
-128 dBm
-128 dBm/
-128 dBm to
2 dB/Div to +21 dBm
139 dBV to
+21 dBm (50 0),
+21 dBm/
-139 dBm to
+10 dBV
+10dBm(600 0),
-141 dBV to
+8 dBV (Hi Z)
Log
-70 dBm
-70 dBm/
-70 dBm to
10
dB/Div to +21 dBm
-81 dBV to +21 dBm (50 0),
+21 dBm/
-81 dBm to
+10 dBV
+10dBm (6000),
-83 dBV to
+8 dBV (Hi Z)
Incremental Accuracy
When calibrated at -40 dBV in Log mode:
L
1, L2 and L3: Within0.2 dB/dB with cumulative errorof
0.25 dB/10 dB.
Lin Mode Range:
20 mV/Div to 200 mV/Divwithin 5%in
1-2-5 sequence.
NOTE
A >sign is displayed adjacent to the reference level
readout when the reference level is not calibrated
due to an incompatible selection of controls.
Display Dynamic Range/Accuracy
Log 10 dB/Div Mode: Dynamic window is 80 dB.
Accuracy is within 0.05 dB/dB to 2 dB maximum.
Log 2
dB/Div Mode: Dynamic window is 16 dB. Ac-
curacy is within 0.1 dB/dB to 1 dB maximum.
1-4
Sweep Characteristics
Frequency Span. Provides calibrated frequency spans
from 50 Hz/div to maximum 500 kHz/div, within 4%, in 1-2-
5 sequence.
Horizontal linearity is
within 4% over the entire 10 div
display.
A O-Hz/Div position is provided
for time domain
operation.
Sweep Rate.
Time per div is selectable from 10 s/div to
0.1 ms/div in a 1-2-5sequence. An AUTO position permits
automatic selection of
optimum time/div for the selected
resolution and span/div.
Sweep rate
accuracy is within 5% of the rate selected.
Triggering. Provides two triggering sources, INT (inter-
nal) and LINE, in
addition to a FREE-RUN position.
When
INT is selected, ac coupled signal components
from the mainframe Trigger Source (left or right vertical
amplifiers) are used.
When LINE is selected, ac
coupled sample of main-
frame line voltage is used.
Three
triggering modes are; NORM (normal), SGL
SWP/READY (single sweep), and MNL SWEEP (manual
sweep).
Trigger level is ~1.0 div of internal signal for both
NORM and SGL SWP modes over the approximate
frequency range of 30 Hz to 500 kHz.
Output Connectors
Video Out. Front-panel pin jack connector suppliesthe
video (vertical)
output signal at an amplitude of 50 mV/div
±5% (about the crt vertical center) with source impedance
of 1 kO.
Horiz Out. A front-panel pin jack connector supplies
horizontal
output signal (negative-going sawtooth that
varies from 0.0 V
dc to approximately -6 V dc) with a
source impedance of 5
kO.
REV. A MAY 1978
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Calibrator. Front panel BNC connector supplies a
calibrated 500 kHz squarewave output signal (derived
from
the analyzer's time base). Output amplitude is within
±0.15 dB of -40 dBV into the impedance of the plug-in
module.
Environmental Characteristics
The 7L5 Spectrum Analyzer will meet the foregoing
electrical characteristics within the environmental limits
of a 7000-Series oscilloscope. Complete details on en-
vi ronmental test procedures, includingfai lure criteriaetc.,
can be obtained from a local Tektronix Field Office or
representative.
Physical Characteristics
Net weight (instrument only): 8 pounds, 12 ounces.
ACCESSORIES AND OPTIONS
Refer to the Replaceable Mechanical Parts List for a
complete listing of thestandard and optional accessories.
Options
7L5 Option 21-(Log Display)
7L5 Option 25-(Tracking Generator)
7L5
Option 28-(Readout)
7L5 Option 30-(Option 21/25)
7L5
Option 31-(Option 21/28)
7L5
Option 32-(Option 25/28)
7L5
Option 33-(Options 21 /25/28)
REV. A MAY 1978
Generallnformatlon-7LS Service
INSTALLATION
Initial Inspection
This instrument was inspected both mechanically and
electrically before shipment. It should be free of mars or
scratches and electrically meet or exceed the specifica-
tion. Inspect the
instrument for physical damage and
check the electrical performance by the Operational
Check procedure provided within the Operators Instruc-
tion Manual. This procedure will verify thatthe instrument
is operating correctly and it will satisfy most receiving or
incoming inspection requirements. If the instrument
specification is to be verified, refer to the Performance
Check
procedure in this manual.
If there is physical damage
or performance deficiency,
contact your local Tektronix Field Office or represen-
tative.
Installation
Install in a 7000-Series mainframeand aftera 10minute
or more warm-up, check performance. To calibrate or
service the 7L5, connect it to the 7000-Series mainframe
interface
through flexible plug-in extenders (see Equip-
ment Required;
Calibration section).
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Calibrator. Front panel BNC connector supplies a
calibrated 500 kHz squarewave
output signal (derived
from
the analyzer's time base). Output amplitude is within
±0.15 dB of -40 dBV into the impedance of the plug-in
module.
Environmental Characteristics
The 7L5 Spectrum Analyzer will meet the foregoing
electrical characteristics within the environmental limits
of a 7000-Series oscilloscope. Complete details on en-
vi ronmental test procedures, includingfai lure criteriaetc.,
can be obtained from a local
Tektronix Field Office or
representative.
Physical Characteristics
Net weight (instrument only): 8 pounds, 12 ounces.
ACCESSORIES AND OPTIONS
Refer to the Replaceable Mechanical Parts List for a
complete listing of thestandard and optional accessories.
Options
7L5 Option 21-(Log Display)
7L5
Option 25-(Tracking Generator)
7L5
Option 28-(Readout)
7L5 Option 30-(Option 21/25)
7L5
Option 31-(Option 21/28)
7L5
Option 32-(Option 25/28)
7L5
Option 33-(Options 21 /25/28)
REV. A MAY 1978
Generallnformatlon-7LS Service
INSTALLATION
Initial Inspection
This instrument was inspected both mechanically and
electrically before shipment. It should be free of mars or
scratches and electrically meet or exceed the specifica-
tion. Inspect the
instrument for physical damage and
check the electrical performance by the Operational
Check
procedure provided within the Operators Instruc-
tion Manual. This procedure will verify thatthe instrument
is operating correctly and it will satisfy most receiving or
incoming inspection requirements. If the instrument
specification is to be verified, refer to the Performance
Check
procedure in this manual.
If there is physical damage
or performance deficiency,
contact your local Tektronix Field Office or represen-
tative.
Installation
Install in a 7000-Series mainframeand aftera 10minute
or more warm-up, check performance. To calibrate or
service the 7L5, connect it to the 7000-Series mainframe
interface
through flexible plug-in extenders (see Equip-
ment Required;
Calibration section).
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