HP 8081A Service manual

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(
Flio- HEWLETT
a:~ PACKARD
OPERATING AND SERVICE MANUAL
300MHz RATE GENERATOR
MODULE
S08iA
PART OF THE 8080 HIGH FREQUENCY
PULSE GENERATOR SYSTEM
SERIAL NUMBERS
This manual applies directly to instrument serial number
1604G 00101
For instruments with lower serial numbers, refer to the
backdating
information in Section 8 of this module
manual.
For instruments
with higher serial numbers, refer to the
Manual
Change sheets at the end of this module manual.
0265
COPYRIGHT HEWLETT·PACKARD GMBH 1975
'------------ 703 BOBLINGEN, HERRENBERGER STR. 110, WEST GERMANY. --.J
MANUAL PART NO. 08081-90001
MICROFICHE PART NO. 08081-90501
Printed in West Germany

CERTIFICATION
The Hewlett-Packard Company certifies that this instrument was thoroughly
tested and inspected and found to meet its published specifications when it
was shipped from the factory. The Hewlett-Packard Company further
certifies that its calibration
measurements are traceable to the U.S. National
Bureau
of Standards to the extent allowed by the Bureau'$ calibration
facilities, or to the calibration facilities
of other International Standards
Organization
mem bers.
WARRANTY AND ASSISTANCE
This Hewlett-Packard product is warranted against defects in materials and
workmanship. This warranty applies for one year from the date of delivpry.
Hewlett-Packard will repair or replace products which prove to be defpctiVl'
during the warranty period provided they are returned to Hewlett-Packard.
No otht-'r warranty is expn'sspd or implied. We are not liahle for
consequential damages.
Service contracts or clistonwr assistancl' agrel'nwnls are availabk for
Ih'wlt:'tt- Packard producl.'i thal require maintenance a.nd repair on -sitl'.
For any assislann" conlat'l your nearpst Hewlelt-Packard Sales and Service
Offiee. Addresses are provided at the back of this manual.

--------------------------- List of Contents/Tables/Illustrations
CONTENTS
Page Section 5Adjustments
5-1
Introduction 1-1
Specifications 1-1
Safety Considerations 1-1
Instruments Covered By Manual 1-1
Description 1-1
Options 1-2
Equipment Required But Not Supplied . 1-2
Equ ipment Available 1-2
Recommended Test Equipment 1-2
Introduction 6-1
Abbreviations 6-1
Replaceable Parts 6-1
Ordering Information 6-1
Introduction 5-1
Safety Considerations 5-1
Test Equipment Required 5-1
Alignment Tool 5-1
Performance Checks 5-1
Related Adjustments 5-1
Duty Cycle and Frequency Adjustments. 5-2
Section 1
1-1
1-4
1-6
1-9
1-11
1-14
1-16
1-18
1-20
Section 2
General Information
Installation
1-1
2-1
5-1
5-3
5-9
5-11
5-13
5-15
5-18
Section 6
6-1
6-3
6-5
6-8
Replaceable Parts
6-1
Introduction 7-1
Recommended Test Equipment 7-1
2-1
2-3
2-5
2-6
2-8
2-10
Introduction 2-1
Initial Inspection 2-1
Preparation For Use 2-1
Installation in 8080A Mainframe 2-1
Operating Environment. 2-1
Storage and Shipment 2-1
Section 7
7-1
7-3
Service
7-1
Section 3Operation
3-1
TABLES
3-1
3-3
3-5
3-7
3-9
3-12
3-21
3-24
3-26
.3-28
3-36
3-40
Introduction 3-1
Panel Features 3-1
Operator's Checks 3-1
Operating Instructions 3-1
Operator's Checks 3-1
Initial Control Settings 3-1
Operating Instructions 3-3
Initial Control Settings 3-3
Normal Mode 3-3
Trigger Mode 3-3
External Gate Mode 3-4
Internal Gate Mode 3-4
Table
1-1
1-2
4-1
6-1
6-2
7-1
7-2
Figure
Page
Recommended Test Equipment
1-2
Specifications 1-3
Performance Test Record 4-7
Abbreviations for Replaceable
Parts List
6-2
Replaceable Parts 6-5
Reference Designators 7-1
Schematic Diagram Symbols 7-2
I LLUSTRA TIONS
Page
Section 4Performance Tests
4-1
4-1
4-3
4-5
4-7
4-8
4-9
4-10
4-11
4-12
4-13
Introduction 4-1
Equipment Required 4-1
Test Record 4-1
Repetition Rate Test 4-1
Trigger Output Test 4-2
External Trigger Mode (Slow) Test 4-2
External Gate Mode (Slow) Test 4-3
Manual Function Test 4-4
External Trigger Mode (Fast) Test 4-5
External Gate Mode (Fast) Test 4-5
1-1
1-2
3-1
3-2
3-3
3-4
3-5
8081 A 300 MHz Rate Generator
Module and Supplied Accessories
1-0
Serial Number Plate 1-1
8081 AControls and Connectors 3-0
Test Set for Operator's Checks 3-2
Suggested Equipment Setup for
Operating Instructions
3-2
Rate Generator Output in Trigger
Mode
3-3
Rate Generator Output in External
Gate Mode
3-4

List of Illustrations/Schematic Diagrams
ILLUSTRATIONS
Figure
4-1
4-2
4-3
4-4
4-5
4-6
4-7
5-1
5-2
6-1
Page
Repetition Rate Test Setup
4-1
Trigger Output Test Setup 4-2
External Trigger Mode (Slow)
Test Setup
4-2
External Gate Mode (Slow) Test
Setup 4-3
Manual Function Test Setup 4-4
External Trigger Mode (Fast) Test
Setup
4-5
External Gate Mode (Fast) Test Setup. 4-5
Duty Cycle Adjustment Test Setup 5-2
Frequency Adjustment Test Setup 5-2
8081 AReplaceable Parts .. , 6-4
SCHEMATIC DIAGRAMS
Diagram Page
1
2
3
Control Board A1
300 MHz Rate Generator Board A2
Distribution Board
A3
7-9
7-11
7-12

SCREWS
CABLE
808TA
Figure 1-1. 8081 A300 MHz Rate Generator Module and Suppl ied Accessories.

,-------------------------------SECTION 1
"--~---------------------- GENERAL INFORMATION
1-1 INTRODUCTION
1-2 This Operating and Service manual contains
information required to install, operate, test, adjust and
service the Hewlett-Packard Model 8081 A 300 MHz
Rate
Generator module.
Figure
1-1 shows the module and accessories supplied.
This section covers instrument identification, descrip-
tion, accessories, specifications, and other basic informa-
tion.
1-3 A microfiche version of this manual is avai-
lable
on 4 x 6 inch microfilm transparencies (order num-
ber
on title page). Each microfiche contains up to 60
photo-duplicates of the manual pages. The microfiche
package also includes the latest Manual Changes supple-
ment as well as all pertinent Service Notes.
1-4 SPECIFICATIONS
1-5 I nstrument specifications are listed in
table 1-2. These specifications are the performance
standard or limits against which the instrument is tested.
is asignificant change to the instrument. The last five
digits are assigned
to instruments sequentially. The con-
tents of this manual apply directly to the instrument
serial number quoted on the title page. For instruments
with lower serial numbers, refer to the backdating infor-
mation in Section 8 of this module manual. For instru-
ments
with higher serial numbers, refer to the Manual
Change
sheets at the end of this module manual. In addi-
tion to change information, the Manual Change sheets
may contain information for correcting errors in the
manual. To keep this manual as up-to-date and accurate
as possible, Hewlett-Packard recommends that you
periodically request the latest Manual Change supple-
ment.
The supplement for this manual is identified with
this manual's print date and part number, both of which
appear on this module manual's title page. Complimen-
tary copies of the supplement are available from
Hewlett-Packard.
HEWLETT - PACKARD GmbH
[1536G00062 ]
BOBLINGEN ..
Figure 1-1. Serial Number Plate
1-6 SAFETY CONSIDERATIONS
1-11 DESCRIPTION
1-7 The Model 8081 A is a Safety Class 1instru-
ment (it has an exposed metal chassis that is connected
to earth via the 8080A system mainframe). This instru-
ment has been designed according to international safety
standards and has been supplied in asafe condition.
1-8 This operating and service manual contains
information, cautions and warnings which must be fol-
lowed
by the user to ensure safe operation and to main-
tain the instrument in asafe condition.
1-9 INSTRUMENTS COVERED BY MANUAL
1-10 Attached to the inside of the instrument side
frame is aserial number plate (figu re 1-1). The first
four digits of the serial nu mber 0nly change when there
1-12 The Model 8081A is a 0-300 MHz Rate
Generator module designed to provide aclock source for
another 8080 system module. The 8081 Ahas four
operating modes:
Normal
Trigger
External Gate
Internal
Gate
In Normal mode, the rate generator is free-running at the
repetition rate selected by the rate controls. In Trigger
mode,
the rate generator is bypassed and the pu Ise
output is merely a shaped version of apulse input from
either an external sou rce or amanual pushbutton. In
External Gate Mode, the rate generator output is gated

Mainframe is required. The 8080A mainframe provides
housing and power supplies for
the 8081 A.
by agate pulse from an external source or amanual
pushbutton. Internal Gate mode can only be useed with
an 8084A Word Generator module. The trigger slope
polarity
and threshold level of external gate/trigger in-
puts is adjustable.
1-18
EQUIPMENT AVAILABLE
1-13 The power supplies for the 8081 Aare pro-
vided by
the 8080A Mainframe.
1-15 The only option for the 8081 ARate Gener-
ator is asecond copy of the operating and service
manual
which can be obtained by ordering option 910.
1-19 The 8081 A is one of a complete range of
rep. rate, timing and output modules that form the
8080 high frequency pulse generator system. Repeti-
tion rates range from 0-1 GHz and the modules are
interchangeable
to enable you to purchase asystem
exactly tailored to your requirements.
1-14
OPTIONS
1-20
RECOMMENDED TEST EQUIPMENT
1-16
1-17
EQUIPMENT REQUIRED BUT NOT
SUPPLIED
To operate the 8081 Amodule, an 8080A
1-21 Equipment required to maintain the 8081 A
is listed in Table 1-1. Other equipment can be substi-
tuted if it meets or exceeds the critical specifications
Iisted in the table.
Table
1-1. Recom me nded Test Equi pment
Instrument Critical Specification Recommended Model Used
in
Mainframe HP 8080A
Performance Tests,
Adjustments
Electronic Counter
up to 350 MHz frequency
HP 5345A Performance Tests,
Adjustments
Sampling Oscilloscope > 300 MHz bandwidth; HP 182C with Performance Tests,
up to 200 mV/div sensitivity;
HP 1810A plug-in Adjustments
up to 0.5 ns/div sweep speed;
50
ohm input impedance
Real
Time Oscilloscope up
to 1 MHz bandwidth;
HP 182C with Performance Tests
up to 1V/div sensitivity;
HP 1804A and
up to 10 Ils/d iv sweep speed;
HP 1821 Aplug-ins
four
input channels
Oscillator up
to 10KHz frequency;
HP 651 BPerformance Tests
up
to 1 V RMS amplitude;
50 ohm output impedance
Pulse
Generator
up to 250 MHz frequency;
HP 8082A
Performance Tests
2ns pulse width;
0.5 V
amplitude; positive-polarity;
50 ohm output impedance;
square wave facility.
50 ohm Feedthrough HP 10100C Performance Tests
Termination
50 ohm Tee Connector
HP 1250-0781
Performance Tests

Model 8081A -------------------------------1-3
Table 1-2. Specifications
TIMING
Repetition rate:
Period
jitter:
EXTERNAL INPUTS
Repetition rate:
Trigger
mode:
Gate mode:
Input impedance:
Trigger level:
Sensitivity:
Slope:
Max. input voltage:
INTERNAL GATE INPUT
Gate duration:
Input impedance:
Amplitude:
High level:
Max
input voltage:
EXTERNAL TRIGGER OUTPUT
Amplitude:
High level:
Duty cycle:
Output impedance:
Transition time (10% to 90%):
Max. external voltage:
INTERNAL OUTPUT
Fan-out*:
Amplitude:
High level:
Duty cycle:
Output impedance:
Transition time (10% to 90%):
Max. external voltage:
OPERATING MODES
Norm:
External trigger:
External gate:
Internal gate:
Manual:
OPTION 910
SIZE
10 Hz to 300 MHz in 8ranges
~ 0.1 %±50 psec
o to 300 MHz, pulse width;;;' 1,7 ns
gate on duration> 1 period of int rep rate,
gate
off duration> 1period + 10 ns
50 ntypical
-lV to +1V
200 mV p-p
neg/pas selectable
±6V
on> 10 ns, off> 20 ns
50 ntypical
~ 500 mV p-p
OV±100mV
±lV
~ 500 mV p-p
OV ± 100 mV
50% ±10%
50 ntypical
~ 1.2 ns
±2V
1
~ 500 mV p-p
OV ± 100 mV
50% ±10%
50 ntypical
~ 1.2 ns
±2V
Repetition rate is determined by front panel controls.
Repetition rate is controlled externally. Shaped input signal is output at both
internal and external trigger outputs.
Gate signal turns repetition rate generator on synchronously.
External input is disconnected. Generator is gated through internal gate input.
All external functions can be triggered manually by pressing
a
pushbutton.
Add itional instrument operating and service manual.
Quarter mainframe width
*Fan-out: max.
number of 8080 system modules which can be driven UPDATE ANOV
76

.----------------------------- SECTION 2
INSTALLATION
2-1
INTRODUCTION
2. Remove the upper two feet from the rear
of the BOBOA mainframe.
2-2 This section provides installation instruc-
tions for the Model BOB1 A 300 MHz Rate Generator
module. It also includes information about initial inspec-
tion and damage claims, preparation for use, and packag-
ing,
storage and shipment.
2-3 INITIAL INSPECTION
2-4 Inspect the shipping container for damage. If
the container or cushioning material is damaged, it
should be kept until the contents of the shipment have
been checked for completeness and the instrument has
been checked mechanically and electrically. The con-
tents of the shipment shou Id be as shown in Figure 1-1.
Procedures for checking the electrical operation are
given in Section 3. If the contents are incomplete, if
there is mechanical damage or defects, or if the 8081 A
does not pass the operator's checks, notify the nearest
Hewlen-Packard Sales/Service office. If the shipping
container is damaged, or the cushioning material shows
signs of stress, notify the carrier as well as the Hewlett-
Packard office. Keep the shipping materials for carrier's
inspection. The HP office will arrange for repair or repla-
cement without waiting for claim settlement.
2-5 PREPARATION FOR USE
2-6 Installation in 8080A Mainframe
ICAUTION]
The following installation procedure must
only be carried out by qual ified service personnel.
3. Remove the 80BOA mainframe top cover.
4. Insert
the BOB1 Ain the required posi-
tion in the BOBOA mainframe (there are no
electrical limitations on the position).
5. Secure the 80B1 A to the 8080A main-
frame using the two screws provided.
6. Connect the internal coaxial cable from
the 8081 A to the word generator, delay,
output amplifier modules or to remote
equipment as required. Connections are
Internal Output and Internal Gate. Acon-
necting cable for the Internal Output is
supplied.
7. Replace
the BOBOA mainframe top cover.
B. Replace the two feet on the rear of the
8080A mainframe.
2-8 Operating Environment
2-9 The 8081 Awill operate within specifications
when
the ambient temperature is between OOC and 55
0
C.
2-7 To operate the BOB1 A, it must first be instal-
led in
an BOBOA Mainframe as follows:
2-10 Storage and Shipment.
1. Switch the mainframe LINE OFF/ON
switch to OFF. Disconnect the power supply
cable from the rear of the 8080A main-
frame.
2-11 The BOB1 A can be stored or shipped at tem-
peratures between -40
oC
and 75
0
C. The instrument should
be protected from temperature extremes which cause con-
densation within the instrument.

2-12 If the instrument is to be shipped to a
Hewlett-Packard Sales/Service Office, attach a tag show-
ing
owner, return address, model number and full serial
number and the type of service required. The original
shipping carton and packaging material may be re-usable
but the Hewlett-Packard Sales/Service office will also
provide
information and recommendations on materials
to be used if the original packing is not available or
re-usable. General instructions for re-packing are as fol-
lows:
1. Wrap instrument in heavy paper or plastic
2. Use strong shipping container. Adouble-
wall
carton made of 350-pou nd test material
is adequate.
3. Use enough shock-absorbing material (3 (
to 4inch layer) around all sides of instru-
ment to provide firm cushion and prevent
movement inside container. Protect control
panel with cardboard.
4. Seal shipping container securely.
5. Mark shipping container FRAG I LE to
encourage careful handling.
6. In any correspondence, refer to instru-
ment by model number and full serial num-
ber.

RATE
• --NHI.- -k.ti::r- -"'1:---
300-100-10'" • -100-10 - 1 -100 - 10
1
. 3 3 - 10 • 1 - 1· 10 - ,- 1 ~ 10-\00
PERIOD
VERNIER
2
'f)(T tNPU1 l.fVEL
GATE ! /::'~
NORM TRIG EXT tNt , ... ,
3 _iii_iii -IV .,v
4
====="~= 5.. ~AN 6. =
EXT INPUT TRIGGER OUTPUT(-)
oEXT INPUT LEVEL control: determines the
threshold voltage of the external trigger input.
Adjustable from -1 V to +1 V.
@NEG-POS-MAN switch: for selecting the slope
polarity and/or source of external trigger signals.
In
the POS and NEG positions, signals are appl ied
via
the EXT INPUT connector. In the MAN posi-
tion,
the MAN pushbutton is used as the trigger.
G) RATE switch: for selecting the range of pulse
repetition rate.
GRate VERNIER: for continuous adjustment of the
repetition rate within the range selected on the
RATE switch. Clockwise rotation increases the
pulse period (reduces the rate). In TRIGGER
mode, the rate controls have no effect.
oMode switch: for selecting the mode of operation
of the rate generator:
NORM-
rate generator free-running at selected repetition
rate.
TRIG-
rate generator output is shaped version of input.
Input is either via the MAN pushbutton or an
external signal into the EXT INPUT connector.
EXT GATE-
gate signal turns rate generator on synchronously.
Repetition rate as selected on rate controls. Gate
'iignal either via the MAN pushbutton or the EXT
INPUT
connector. Max. gate frequency 150 MHz.
INT
GATE-
external input is disconnected. Gate signal is pro-
vided
internally by the word generator module and
Figure 3-1. 8081 AControls and Connectors
(~)
turns the rate generator on synchronously. Repeti-
tion rate as selected on the rate controls.
MAN
pushbutton: for generat;ng external trigger
signals
when in TRIG and EXT GATE modes. The
NEG-POS-MAN switch must be in the MAN posi-
tion.
EXT INPUT
connector: DC coupled input to
which external trigger/gate signals are applied.
Input impedance is 50 ohms. Maximum input
level ;s ±6V.
TRIGGER OUTPUT connector: provides negative
output pulses in all modes of operation. In TRIG.
mode the output pulses are related to the trigger
input and not the repetion rate generator. Maxi-
mum external voltage ;s ±2V.

SECTION 3J
'----------------------------- OPERATION
3-1
INTRODUCTION 3-12
Initial Control Settings
3-2 This operating section explains the function
of the controls and connectors and describes the opera-
tors checks and
typical operati ng modes of the 8081 A
300 MHz Rate Generator module.
3-3 Panel Features
3-4 Front panel controls and connectors are
shown in figure 3-1. Description numbers match the
numbers on the illustration.
SOSl A:
1 RATE range switch 300-100 MHz
2Rate VERN IER
CCW
3Mode switch NORM
5NEG-POS-MAN switch MAN
Oscilloscope:
Sensitivity
100mV/div
Trigger Channel A
Timebase EXPANDED, 1ns/div
3-5 Operator's Checks
3-13 The repetition rate of the output should be
approximately 300 MHz.
3-6 Use the Operator's Checks (paragraph 3-91
to verify that the SOSl A is functioning correctly. The
SOSl Amust be installed in an SOSOA Mainframe for
these checks. Thus it is important to remember that any
fault that is found may be in the BOSl ARate Generator
or the 80S0A Mainframe. If the mainframe is suspected,
carry
out the SOSOA Performance Checks.
3-7 Operating Instructions
3-8 The Operating Instructions (paragraph
3-21 Iconsist of anumber of procedures that explain in
detail the
function of each of the 80S1 Acontrols. All
operating modes are described. However, 1nternal Gate
mode
can only be used if an 8084A 300 MHz Word
Generator module is avai lable.
3-9 OPERATOR'S CHECKS
3-10 The test set for the Operator's Checks is as
shown in figure 3-2. The 8081 ARate Generator mo-
dule must
be mounted in an S080A Mainframe.
3-11 Set the LI NE switch 9on the 8080A Main-
frame to ON.
3-14 Turn the rate VERNIER 2 fully clockwise.
The repetition rate should
be approximately 100 MHz.
3-15 Repeat repetition rate checks for RATE
ranges 100-10 MHz and 10-1 MHz at the CCW and CW
positions of the rate VERNIER. The repetition rates
should
be approximately as shown on the RATE range
switch.
3-16 Switch off the oscilloscope. Replace the
oscilloscope sampling plug-in
with real time dual channel
vertical and timebase plug-ins. Reconnect the TRIGGER
OUTPUT 8 to the channel A input and switch on the
osciIloscope.
3-17 Repeat repetition rate checks for RATE
ranges 1MHz -100 KHz, 100-10 KHz, 10-1 KHz,
1
KHz-l00 Hz and 100-10 Hz at the CCW and CW
positions of the rate VERNI ER. The repetition rates
should be approximately as shown on the RATE range
switch.
3-18 Set BOB1A mode s'.'vitch 3 toTRIGand
press the MAN pushbutton 4 several times.
3-19 Output should go high when button is pres-
sed and low when button is released.

8080A
MAINFRAME
9
RATE
,--MH.-- -kH:r- -Hl-
300-100-10 - 1 -100-10 - 1 -100 ... 10
1J
~ - IU - I - • - I1J - , . t - 11)- iL'.l'J
P 'RIOI>
GAlE
t~OR" HUG EXT INT
VERN1£R
EXT INPUT LEVEL
ascI LLOSCOPE
WITH 1GHz
SAMPLING PLUG-IN
D
CH
A
50 OHM COAXIAL CABLE
Figure 3-2. Test Set for Operator's Checks
NEG pOs ro\AN---~~
OSCI LLOSCOPE
D
VERNIER
EXT H4PUT LEVEl
2
-,
GAtE
NQR,lOI TRIO EXT fN:r
J J - t - 1 - 1 - ~[JI -I - 1 -' ·1
RATE
J --I\lH.-- -kHl- -H.;z;-
~O-100-'O - 1 - toO -10 - ~ -100 -10
..
1
9
PULSE GENERATOR
-------0---0
- - - - - 0- --- - -
OUTPUT
500HM
TEE
50 OHM
COAXIAL
CABLES
DUAL TIMEBASE
CHANNE LPLUG·IN
VERTICAL EXT
PLUG·I NINPUT
o 00
L....- CH. - CH.----'
A B
Figure 3-3. Suggested Equipment Setup for Operating Instructions

3-27 In Normal mode, the repetition rate genera-
tor is free-running at the frequency set on the rate con·
trois. The pulse output is the same as on the oscilloscope
(the trigger output is identical to the pulse output). The
pulse duty cycle is 40-60%.
3-20 Set BOB1 A mode switch 3 to EXT. GATE
and press the MAN pushbutton. The repetition rate
should start when the button is pressed and stop when
the button is released. When the button is pressed, i. e.
when the gate opens, the first pulse should always start
at the beginning. However, when the button is released,
i. e. the gate closes, the last pulse may be cut short.
3-26
Normal Mode.
3-21 OPERATING INSTRUCTIONS
3-28
Trigger Mode
3-22 Asuggested equipment setup for the Operat-
ing
Instructions is shown in figure 3-3.
The B081 ARate Generator must be mounted in an
BOBOA Mainframe. The following procedure is designed
to give afull understanding of the function of each of
the 8081 A operating modes.
3-23 Set the LINE switch on the 8080A Main-
frame to ON.
3-29 In TRIGGER mode, the repetition rate of
the output is independent of the internal repetition rate
generator. The output is, in fact, apulse-shaped version
of the input signal. The input can be either external via
the EXT INPUT (-j) or local using the MAN pushbut-
ton ®. For external triggering, an external signal source
is required. The test set is as shown in figure 3-3. The
changes in control settings are as follows.
3-24
Initial Control Settings
8081A
CD RATE range switch 1 MHz-100 KHz
~ Rate VERNIER CCW
~ Mode switch NORM
@EXT INPUT LEVEL +1 V
@NEG-paS-MAN switch pas
Oscilloscope:
Timebase 2psec/div
Trigger Channel Ainternal
Pulse
Generator: switched off.
8081A:
@Mode switch TRIG
@NEG-POS·MAN switch pas
Pulse Generator:
Switch pulse generator on.
Set pu Ise period to about 15 fJ.sec.
Set pulse width to about 8 fJ.sec.
Set pulse amplitude to 2V and polarity to
pas.
Set the oscilloscope to trigger from chan-
nel Binternally.
3-25
modes:
The 8081 Ahas four different operating
Normal (NORM)
Trigger (TRIG)
External
Gate (EXT GATE)
Internal
Gate (INT GATE)
3-30 The oscilloscope display should be as shown
in figure 3-4. The 8081 A output should only be
delayed
on the external input by the internal circuitry
delay of the 8081 A
EXTERNAL
IL
INPUT
Ov
-L
I
RATE
ov
II
GENERATOR
-O.6V
I
OUTPUT
II
f
II
---J !--
fixed delay
Figure 3-4. Rate Generator Output in Trigger Mode.

3-31 Vary the EXT INPUT LEVEL switch ®and
note that the trigger output disappears when the thre-
shold level reaches
approximately +0.2V. Set the exter-
nal input level to -1 V.
3-32 Set the NEG-POS-MAN switch @to NEG.
Set
the pulse generator output polarity to negative.
This gate signa Ican come from either an external source (
via
the EXT INPUT connector (J) or locally using the
MAN pushbutton ®. When the gate signal switches on,
the first output pulse is always started at the beginning.
When
the gate signal switches off, the pulse is terminated
immediately, i. e. the last pulse may be cut short.
3-37 In External Gate mode the repetition rate
generator
output is enabled/disabled by agate signal.
3-33 The oscilloscope display should be similar to
that shown in figure 3-4 except that the external input
is anegative-going pulse.
3-34 Vary the EXT INPUT LEVEL switch ®and
note that the trigger output disappears when the thre-
shold level reaches
approximately -O.2V.
3-35 As mentioned previously, the pulse output
in trigger mode can also be produced using the MAN
pushbutton ®. First set the NEG-POS-MAN switch ®
to MAN. This transfers the trigger input from the EXT
INPUT
connector (J) to the MAN pushbutton @ . Set
the oscilloscope timebase to about 0.2 sec/em and trig-
ger internally. Press
the MAN pushbutton @and note
that the pulse output goes high when the button is pres-
sed and low when it is released. The EXT INPUT
LEVEL control ®has no
effect in this mode.
Internal Gate Mode
3-39 Set the NEG-POS-MAN switch @ to POS
and the EXT INPUT LEVE Lcontrol ® to -1 V. Vary
the rate VERNIER C2>. Note that the last pulse may be
cut short by the gate turning off (see figure 3-5).
3-38 Set the Mode switch ® to EXT GATE. Set
the oscilloscope timebase to 2usee/em and trigger inter-
nally. Press
the MAN pushbutton and note that the rep.
rate generator runs
at the selected rate for as long as the
button is held down.
3-41 Internal Gate mode can only be used if an
8084A 300 MHz Word Generator module is available. In
this mode of operation the gate pulse for the rate genera-
tor comes from the word generator via an internal con-
nection. This gate enables
the rate generator output in
the same way as an external gate. The purpose of this
mode
is to enable an exact number of data bits to be
gated out of the word generator.
3-40
External Gate Mode.
3-36
EXTERNAL OV
INPUT
Gate on Gate off
RATE
GENERATOR Ov-------;
OUTPUT
Last pulse may not be completed
Figure 3-5. Rate Generator Output in External Gate Mode.

,.------------------------------ SECTION 4
L-- PERFORMANCE TESTS
4-1 INTRODUCTION
EQUIPMENT
4-2 The procedures in this section test the Model
8081 A's electrical performance using the specifications
of Table 1-2 as the performance standards. All tests can
be performed without access to the interior of the in-
strument. Asimpler operational test
is included in sec-
tion 3under Operator's Checks.
Counter HP 5345A
PROCEDURE
4-3
EQUIPMENT REQUI RED
1. Set up the equipment as shown in figure 4-1 and
set the controls as follows:
4-4 Equipment required for the performance
tests
is listed in the Recommended Test Equipment table
in section 1.
Any equipment that satisfies the critical
specifications given in the table
can be substituted for
the recommended model.
8081A:
RATE
range , 300MHz-l00MHz
Rate VERNIER CCW
Operating Mode switch NORM
NEG-POS-MAN switch
POS
4-5 TEST RECORD
SPECI FICATION
DESCRIPTION
2.
Using the counter, measure the Model 8081 Aout-
put frequency at the
following repetition rate
settings.
8081A
RATE VERNI
ER RESULT
300MHz-100MHz
CCW
>300MHz
300MHz-100MHz CW <100MHz
100MHz- lOMHz CCW
>100MHz
100MHz- 10MHz CW
<10MHz
1
OM Hz-
1MHz
CCW
>10MHz
10MHz-
1MHz CW
<1MHz
1
MHz-100KHz CCW
>1MHz
1
MHz-100KHz CW
<100KHz
100KHz- 10KHz
CCW >100KHz
100KHz- 10KHz CW
<10KHz
10KHz- 1KHz
CCW
>
10KHz
10KHz- 1KHz
CW
<1KHz
1
KHz-100Hz
CCW
>1KHz
1
KHz-100Hz CW
<100Hz
100Hz- 10Hz CCW
>100Hz
100Hz- 10Hz CW
<10Hz
o
8080A MAINFRAME
808lA
4-6 The results of the performance tests can be
tabulated on the Test Record at the end of the proce-
dures. The Test Record lists all
of the tested specifica-
tions and
their acceptable limits. Test results recorded at
incoming inspection
can be used for comparison in
troubleshooting and after repairs or adjustments.
4--7 REPETITION RATE TEST
The output frequency of the Model 8081 A is checked
over the
full repetition rate range.
Repetition Rate ., 10Hz to 300MHz
Figure
4-1. Repetition Rate Test Setup

4-8
TRIGGER OUTPUT TEST
3.
Measure Amplitude, Baseline and Duty Cycle.
SPECIFICATION
Trigger Output Pulse ,-.6V ± 50mV
to OV ± 50mV
Duty Cycle 50 %±10 %
I-t on J-t Off-J
Baseline
DESCRIPTION
The trigger output pu Ise parameters are tested.
Amplitude should be . , 6V ± 50mV
Baseline should be OV ± 50mV
Duty Cycle shou Id be 50 % ~ 10 %
ton
x100%
period
4-9 EXTERNAL TRIGGER MODE
(SLOW) TEST
Duty cycle =
o
SAMPUNG
OSCI LlOSCOPE
D
01
8080A MAINFRAME 80S1A
Figure 4-2. Trigger Output Test Setup
SPECI FICATION
EQUIPMENT
The repetition rate output is controlled externally. The
trigger and internal
outputs are pulse-shaped versions of
the trigger input.
Sampling oscilloscope
HP 182C Mainframe
with 1810A plug-in DESCRIPTION
PROCEDURE
1. Set up the equipment as shown in figure 4-2 and
set the controls as follows:
The function of the Model 8081 A is tested in external
trigger mode using
an external sinewave generator to
apply atrigger signal of 10KHz.
so OHM
TERL4lNATlON
,
REI>,L TIME
OSCILI,OSCOP~
RATE range 300MHz-100MHz
Rate VERNIER , .. , , CW
Operating Mode switch NORM
NEG-POS-MAN switch
POS
8081A:
Oscilloscope
50QHM T£~
2.
Sensitivity .. , 200mV/div
Trigger internal
Timebase mode expanded
Timebase -direct 20ns/div
Timebase -expanded 2ns/div
Set Frequency to 100MHz on screen using Rate
VERNIER.
Figure 4-3. External Trigger Mode (Slow) Test Setup
EQUIPMENT
Oscillator , HP 651 B
Real Time Oscilloscope HP 182C Mainframe
with 1804A and 1821 Aplug-ins
50 Ohm Feedthru Termination
HP 10100C
/

PROCEDURE
1. Set up the equipment as shown in figure 4-3 and
set the controls as follows:
5.
Set NEG-POS-MAN switch to NEG and repeat
steps 3and 4observing the pulses. The Model
8081 A output shou Id trigger on the negative
half-cycles
of the oscillator output.
8081 A:
SPECIFICATION
RATE range 100KHz-10KHz
Rate VERNIER CCW
Operating Mode switch TRIG
EXT INPUT LEVEL center
NEG-POS-MAN switch
pas
4-10
EXTERNAL GATE MODE (SLOW)
TEST
Oscilloscope: Gate
signal turns rep. rate generator on synchronously.
Sensitivity (both channels) 1 V/div
Trigger. ,external
Timebase main 20ps/div
Oscillator:
DESCRIPTION
The function of the Model 8081 A is tested in external
gate mode using
an external sinewave generator to apply
agate
signal of 10KHz.
Frequency
10KHz
Amplitude 1VRMs
3. Check that during the positive slope of the oscilla·
tor output apositive pu Ise output occurs.
4. Turn EXT INPUT LEVEL control from positive to
negative and observe waveforms.
so OHM TEE
SQOHM
TERMINATION
REAl. ,IME
OSCU.LOSCOPE
Figure 4-4. External Gate Mode (Slow) Test Setup
EQUIPMENT
Oscillator , HP 651 B
Real Time Oscilloscope HP 182C Mainframe
with 1804A and 1821 Aplug-ins.
50 Ohm Feedthru Termination
HP 10100C
i*-- Propagation delay
I
Display oscillator output and Model 8081 A output
on screen
8081A
OUTPUT
2.
OSCILLATOR
OUTPUT
PROCEDURE
OSCILLATOR
OUTPUT
8081 A
OUTPUT
Threshold lever""" +1 V -1V
1.
Set up the equipment as shown in figure 4-4 and
set the controls as follows:
8081A:
RATE range. ,
100KHz-10KHz
Rate VERNIER CCW
Operating Mode switch GATE EXT
EXT INPUT LEVEL center
NEG-paS-MAN switch
pas

Oscilloscope:
4-11
MANUAL FUNCTION TEST \
Sensitivity (both cha nnels) 1VIdiv
Trigger external SPECI FI
CATION
Timebase, main 20~s/div
All external functions can be triggered manually by
pressing apushbutton.
Oscillator:
o 00
500HM
HRMINATJON
SOBOA MAINfRAME SOS1A
REAL TIME
ascI LLOSCO~E:
Frequency 10KHz
Amplitude 1
VRMs
Display oscillator output and 8081 A output on
screen.
2.
3.
Check that during the positive slope of the oscilla-
tor output apulse burst appears. Figure
4-5. Manual Function Test Setup
EQUIPMENT
Threshold level
OSCILLATOR
OUTPUT
I I
I I
II
~ r--Delay of 1/2 period
8081A i,hnnnn rl -
OUTPUT -----.lJ UUUUU ~
OV
Real Time Oscilloscope HP 182C Mainframe
with 1804A and 1821 Aplug-ins
PROCEDURE
1. Set up the equipment as shown in figure 4-5 and
set the controls
as follows:
8081 A:
4. Turn EXT I NPUT LEVEL control from positive to
negative and observe the waveforms.
RATE range
100KHz-10KHz
Rate VERNIER , .. , CCW
Operating Mode switch GATE EXT
EXT INPUT LEVEL -
NEG-POS-MAN switch ,
MAN
Oscilloscope:
OSCILLATOR II
OUTPUT -+ __ I_
II
I I
II
II
I I
II
II
8081A IlJU
OUTPUT~ ~ __ ~
I
I
I
I
I I
I I
11nJllUlJlJt:
2.
Sensitivity ,1V/div
Trigger, , , internal
Timebase, main ,10IlS/div
Press MAN pushbutton. As long as the Man button
is pressed apulse train should be visible
~MAN button--..J
Ipressed I
_llll~11Ill·I.lml-UIJ/JINI.ll- OV
Threshold level --+ +1 V
-1V
Note that the last pulse will be cut off as soon as
the gate closes.
3. Set the Operati ng Mode switch to T RIG. Press the
MAN pushbutton. As long as the MAN button is
pressed the output should be OV.
5. Set the NEG-POS-MAN switch to NEG and repeat
steps 3and 4observing the pulses.
The 8081 A
output should be gated on the negative half-cycles
of the oscillator output.
r-
MAN button~
pressed I