Tektronix 7L5 User manual

Tektronix.
COMMITTED TO EXCELLENCE
PLEASE CHECK FOR CHANGE INFORMATION
AT THE REAR OF THIS MANUAL.
7L5
SPECTRUM ANALYZER
OPTIONS
INSTRUCTION MANUAL
Tektronix, Inc.
P.O. Box 500
Beaverton, Oregon 97077 Serial Number
070-2155-03 / FIRST PRINTING OCT 1976
Product
Group
26
Revised
JAN
1982

Copyright © 1976, 1977, 1978 Tektronix, Inc. All rights
reserved. Contents of this publication may not be
reproduced in any form without the written permission of
Tektronix, Inc.
Products of Tektronix, Inc. and its subsidiaries are
covered by U.S. and foreign patents and/or pending
patents.
TEKTRONIX, TEK, SCOPE-MOBILE, and el are
registered trademarks of Tektronix, Inc. TELEQUIP-
MENT is a registered trademark of Tektronix U.K.
Limited.
Printed in U.S.A. Specification and price change
privileges are reserved.

—
7L5 Options
GENERAL INFORMATION
INTRODUCTION
This manual contains documentation for the 7L5
Spectrum Analyzer Options. Each is a complete and
separate section or supplement to the manual. Changes
and corrective information are added, at the back of the
manual. This information is incorporated into the respec-
tive manual text and diagrams when the option section is
reprinted. History information is included with the up-
dated data. Original pages are identified by the symbol @,
revised pages by a revision date on the lower inside corner
of the page. These options add an assembly, with its part
number; to the 7L5 instrument. The suffix portion of the
part number signifies updating process of the assembly.
Up-dated manual supplements may contain information
that is not applicable to your instrument; however as
previously stated, the manual does contain history infor-
mation.
Depending on the production model of the 7L5, it may
be impractical to field install some option assemblies.
Contact your local Tektronix Field Office or representative
for information.
INSTALLATION AND REPACKAGING
Initial Inspection
The instrument was inspected both mechanically and
electrically before shipment. It should be free of mars or
scratches and. electrically meet or exceed all
specifications. To confirm this, inspect the instrument for
physical damage that may have occurred in transit and
test the electrical performance by following the Operating
Instructions and Performance Check Procedure in the
section applicable to the Option. If there is damage, or if
the instrument does not perform, contact your local
Tektronix Field Office or representative.
Installation
These options are normally shipped attached to the 7L5
and ready to plug into the 7000-Series mainframe. If the
option is shipped as a field modification kit, instructions
on how itis installed to the 7L5 will be included with the kit.
After installation, plug the 7L5 with option into a 7000-
Series mainframe, and proceed as directed in the
’ Operations section of this manual. (Both Options 25 and
21 require a mainframe with readout.)
Repackaging for Shipment
If a Tektronix instrument is to be shipped to a Tektronix
Service Center for service or replacement, attach a tag
showing, owner (with address) and the name of an
individual at your firm that can be contacted. Include
complete instrument serial number and a description of
the service required.
Save for re-use the shipping container your instrument
was shippedin. If the original packaging is not available,
or is unfit for use, repackage as follows:
1. Obtain a shipping container made of heavy cor-
rugated cardboard or wood with inside dimensions of no
less than six inches more than the instrument dimensions;
this will allow room for cushioning. Refer to Table 1 for
carton test strength requirements.
2. Wrap the instrument in heavy paper or polyethylene
sheeting. Protect the front panel with urethane foam or
cardboard strips.
3. Cushion the instrument on all sides by tightly
packing dunnage or urethane foam between the carton
and the instrument allowing three inches on all sides.
4. Seal the carton with shipping tape or an industrial
stapler.
TABLE 1
Gross Weight (Ib) Carton Test Strength (Ib)
10-30 275
30-100 375
120-140 500
140-160 600
If you have any questions, contact your local Tektronix
Field Office or representative.

—_
—
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7L5 Option 21
7L5 OPTION 21
Log Sweep
General
Information
IRIG
PROPORTIONAL
BANDWIDTH
SUBCARRIER
CHANNELS
The
7L5
Option
21
provides
the
additional
feature
of
an
LOWER
|
CENTER
|
UPPER
|
BAND
IRIG
logarithmic
frequency
span
(250
Hz
to
222
kHz)
LIMIT
FREQ
LIMIT
WIDTH
display.
Because
the
display
is
generated
from
three
CHANNEL
;
(CPS)
(CPS) (CPS)
(CPS)
sweeps,
covering
a
decade
of
frequency
each,
digital
storage
memory
operation
is
used.
Resolution
and
sweep
:
ere
ay
ane
“
time
are
automatically
controlled
to
provide
an
amplitude
é
518
560
602
84
calibrated
display
for
the
data
acquisition
time.
Signal
3
675
730 785
110
acquisition
time
for
one
display
is
no
more
than
2.5
4
888
960
1,032
144
seconds.
A
Sweep
Inhibit
feature
will
store
and
display
any
5
1,202
1,300
1,398
196
full
span
log
display
until
SWP
INHIBIT
is
switched
off.
6
1,572
1,700
1,828
256
This
is
equivalent
to
single
sweep
operation.
f
2,127
2,300 2,473
346
8
2,775 3,000
D200
450
)
3,607
3,900 4,193
586
10 4,995
5,400
5,805
810
ae ak
6,799 7,350 7,901 1,102
9,712 10,500 11,288 1,576
13,412 14,500 15,588 2,176
20,350 22,000 23,650 3,300
27,750 30,000 32,250 4,500
37,000 40,000 43,000 6,000
48,560 52,500 56,440 7,880
64,750 70,000 75,250 10,500
86,025 93,000 99,975 13,950
114,700 124,000 133,300 18,600
152,625 165,000 177,375 24,750
@ An IRIG graticule overlay is provided as a standard
accessory. The graticule can be inserted over the face of
the crt behind the crt bezel. The following table lists
proportional bandwidth subcarrier channels.
Sees
Ua,
eb
bhwNnh
NSD
ed
ee
-00O
0
NWN
L@
NOILdO
@
Option
21
Page
i

SECTION 1
SECTION 2
TABLE OF CONTENTS
SPECIFICATIONS
Electrical Characteristics
Environmental Characteristics
Accessories
OPERATING AND PERFORMANCE CHECK INSTRUCTIONS
Introduction
Function of Controls and Connectors
Operational Check
1. Preliminary Preparation
2. Check Frequency Range and Display Flatness
3. Verify Sweep Inhibit Operation
7L5 Option 21
Page
—_
oot
'
2
2-1
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.
SECTION 3
SECTION 4
SECTION 5
SECTION 6
SECTION 7
SECTION 8
CALIBRATION
Equipment Required
1. Preliminary Preparation
2. Calibrate the Sweep Span to 10 kHz
3. Calibrate the Log Sweep
4. Calibrate Resolution Bandwidth
CIRCUIT DESCRIPTION
General
Detailed Description
MAINTENANCE INSTRUCTIONS
Introduction
Preparing the Instrument for Service
Replacing the Assembly
REPLACEABLE ELECTRICAL PARTS
DIAGRAMS
REPLACEABLE MECHANICAL PARTS
CHANGE INFORMATION
3-1
4-1
Option 21 Page ii

Se
-
4)
,
|
—)J
—)
__]
Fig. Option 21. 1-1. 7L5 Option 21 (Log Sweep).
7L5 Option 21 REV. A FEB 1978
—J
—J
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Section 1—7L5 Option 21
SPECIFICATIONS
ELECTRICAL CHARACTERISTICS
The following characteristics and features apply to the
Option 21 (Log Display) portion of the 7L5 Option 21
Spectrum Analyzer. 7L5 characteristics are not affected
by this option. These characteristics are applicable over
the environmental specifications criteria for the 7000-
Series mainframe.
Frequency Range (Log Display): 250 Hz to 222.25 kHz,
in increments of; 250 Hz—2.25 kHz, 2.25 kHz— 22.25 kHz,
and 22.25 kHz—222.25 kHz.
Signal aberration (spread or overlap) generated at the
crossover points (i.e. 2.25 kHz, 22.25 kHz, etc.) shall
not exceed 0.5 minor division.
Display Flatness: +0.5 dB, —1.5dB from 300 Hz to
180 kHz.
Acquisition Time/Full Log Display: Not more than 2.5
seconds. When 220 kHz IRIG (Log Display) is on, all
except the REFERENCE LEVEL, Display Mode, and
MAX HOLD selectors on the 7L5 are disabled. DOT
FREQUENCY is not operational. When 220 kHz IRIG
(Log Display) is off, the 7L5 operation is normal. When
SWP_ INHIBIT is enabled (illuminated) with Log
Display, sweep operation is similar to single sweep
mode. Data acquired during full log span period, is
stored and displayed until the sweep is retriggered by
switching SWP INHIBIT off.
ENVIRONMENTAL CHARACTERISTICS
As previously described, the instrument will meet the
electrical characteristics over the environmental limits of
the 7000-Series mainframe. Complete details on test
procedure are described in the mainframe manual.
Operating and Storage Requirements
Operating Temperature Range: 0°C to +55°C.
Storage Temperature Range: —54°C to +75°C.
ACCESSORIES
Standard Accessories
Manual, Instruction
IRIG Log Graticule for 7L5 Option 21 331-0421-00
Option 21 Page 1-1

a)
J)
—_]
4

Section 2—7L5 Option 21
~ _ OPERATING AND PERFORMANCE CHECK
INSTRUCTIONS
Introduction
This section describes the function of front panel
selectors and provides an operational or performance
check procedure. This operational check can be used to
verify that the instrument is operating satisfactory and will
serve as a guide for incoming inspection.
The Option 21 assembly provides a logarithmic display
over the Inter Range Instrumentation Group (IRIG) re-
quirements for the frequency range 250 Hz to 222.25 kHz.
Log display is front panel selectable. Normal linear
operation of the 7L5 is unchanged when the Option 21 is
off. A IRIG graticule overlay, with subcarrier channels
noted, is a standard accessory.
Function of the Panel Selectors
Two momentary pushbutton switches illuminate when
their function is asserted.
220 kHz IRIG: Switches the spectrum analyzer span toa
300
Hz to 180 kHz log display. When on, all except the 7L5
Reference Level, Display Mode, (Log-Lin) and Max Hold
selectors are disabled. Sweep consists of three segments
with breakpoints at 2.25 kHz and 22.25 kHz. When off, the
7L5 operation is normal.
SWP INHIBIT: When activated (illuminated) the instru-
ment will complete a full log display. The data acquired
will remain stored and displayed until the switch is pushed
again to change the state to off.
OPERATIONAL CHECK
This check will verify that the Option 21 assembly
meets the electrical charactersitics specified.
Equipment Required or Recommended
Test equipment specifications are the minimum re-
quired for these checks.
1. Two Sine Wave Signal Generators: Frequency
range 250 Hz to 250 kHz. Variable output level. Output
impedance 50 9 or 600 Q. TEKTRONIX SG 502 Oscillator
of the TM 500 Series Test and Measurement instruments.
2. An "L"-Series plug-in module that matches the
source impedance of the signal generator.
3. One, BNC "T" Adapter: Tektronix Part No. 103-
0030-00.
1. Preliminary Preparation
a. Plug the 7L5 Option 21 into a 7000-Series main-
frame with readout. Install an "L" series plug-in module
into the 7L5. (Plug-in module input impedance should be
the same as the signal generator output impedance.)
b. Turn the mainframe power on and allow a few
minutes (about 5) warmup.
c. With the Log Display (220 kHz IRIG) off, calibrate
the 7L5 span and position the display as described in the
7L5 Operating instructions.
2. Check Frequency Range and Display Flatness
a. Apply the output from two signal generators
through a BNC "T" connector and coaxial cable to the
Input of the 7L5 plug-in module.
b. Set the frequency of one generator to 300 Hz and
the frequency of the other generator to 180 kHz. Adjust
the output level of both generators to 0 dBm.
c. Switch the 7L5 Display Mode to 10 dB/DIV and the
220 kHz IRIG Log Display on.
d. Check—the display for the 300 Hz and 180 kHz
signals within +0.5, —1.5 dB, of 0 dBm. Note that only the
Display Mode and Reference Level selectors of the 7L5 are
functional when the Log Display is active.
3. Verify Sweep Inhibit Operation
a. Activate the sweep inhibit mode by pressing the
SWP INHIBIT pushbutton.
b. Verify that the sweep is locked out, at the comple-
tion of one sweep by changing the Display Mode to
2 dB/DIV of LIN and observe that the display does not
change.
Option 21 Page 2-1