Tektronix 7B70 User manual

TA BLEO F CO
N T EN TS
SE CTION 1
S E CTIO
N 2
S PE CI F ICATIO
N SP
age
Intro d uction
1-1
E lectrical C h
aracteristics
1-1
Swee p
R ate
1-1
Swee p
Accuracy
1-1
Swee p
L ength
1-1
Swee p
H
ol
d -Off Time
1-1
E xternal
H orizontal Am p lifier
1-1
Deflection F actor 1-1
F re q uency R es p onse
1-2
Trigger Sensitivity
1-2
Internal
Trigger J itter
1-2
E xternal Trigger
In p ut
1-2
Ρ - Ρ
Auto Sensitivity 1-2
E nvironmental
C h aracteristics
Altitu d
e
1-2
Ph
ysical C h aracteristics
F inis h
1-2
Dimensions
1-2
W eig h t
1-2
O PER ATI NG I N ST RU
CTIO NS
General
2-1
Installation
2-1
F ront Pan el Controls
2-1
Test Setu p Ch art
2-4
General O p erating
Information
2-4
Swee p Calibration
C h ec k
2-4
Sim p lifie d Op
erating Instructions
2-4
N ormal Swee p2-6
M agnifie d Swee
p2-6
Delaye d Swee
p2-6
P us h button
Switch L ogic
2-6
Triggere d L ig h t
2-6
Trigger M ode
2-7
Trigger Cou p
ling
2-8
Trigger Source
2-9
Trigger Slo p e2-10
Trigger L evel
2-10
H
orizontal Sweep R ate
2-10
Sweep M agnifier
2-12
H orizontal P osition
Control
2-12
Display M od e2-12

TA
BLE O F CO
N T EN TS (cont)
S E CTIO N 2 O PER ATI NG I N ST RU CTIO N S
(cont) Page
A pp lications
2-13
General 2-13
F
re q uency Com p arison 2-13
Time Duration
M
easurements 2-14
Determining
F
re q uency 2-15
Risetime
M
easurements 2-15
Delaye d Sweep Time M easurements
2-16
Delaye d Swee p M ag n ification 2-17
Dis p laying Com p lex Signals U sing Delayed Swee p2-18
Pulse J itter M easurements 2-18
Χ - Υ Ph ase M easurements 2-19
S E CTIO N 3 CI RC U IT D E SC R I P TIO N
Intro d uction 3-1
B loc k Diagram Descri p tion
3-1
Detaile d Circuit Descri p tion 3-1
Trigger In p ut 3-1
Trigger Am p lifier 3-2
In p ut Stage 3-3
Peak Detector 3-3
Slo pe Com p arator 3-4
Out p ut Stage 3-4
Trigger Generator 3-4
Trigger Pulse Generator 3-4
Sweep Gate Stage 3-4
Triggere dH ol d -Off Stage 3-5
B rig h t L ine Auto 3-5
External H orizontal Am p lifier 3-5
Time- B ase Generator 3-6
General 3-6
N
ormal
Trigger M
ode O p eration 3-7
Single
Swee p
Op eration
3-8
Alternate O p eration 3-8
Delaye d Swee p Op eration 3-9
H orizontal Pream p3-9
Rea dou t B loc k3-9
SE CTIO N 4 M AI N T ENAN C E
P
reventive M aintenance 4-1
General 4-1
Cleaning
4-1
V isual Ins p ection
4-1
Transistor C h
ec
k s
4-1
Recalibration 4-1

TABLE OF
CONTENTS (cont)
CHANGE INFORMATION
Abbreviations and
symbols used in this manual are based on or
taken directly from IEEE
Standard 260 "Standard Symbols
for
Units", MIL STD-12B
and other standards of the electronics
industry . Change
information, if any, is located at the rear of
this
manual .
SECTION 4 MAINTENANCE
(cont) Page
Troubleshooting 4-2
Troubleshooting Aids
4-2
Troubleshooting Equipment
4-3
Troubleshooting Techniques
4-3
Corrective Maintenance
4-5
Obtaining Replacement Parts
4-5
Soldering Techniques
4-6
Component Replacement
4-7
Instrument Repackaging
4-8
SECTION 5 PERFORMANCE CHECK/CALIBRATION
Introduction
5-1
Test Equipment Required
5-1
Short Form Procedure
5-2
Performance Check/Calibration Procedure 5-4
General
5-4
Preliminary Control Settings
5-4
Check/Adjust Steps (refer to Short-Form
Procedure
for index to steps)
5-5
SECTION 6 ELECTRICAL PARTS LIST
Abbreviations and
Symbols
Parts Ordering Information
Index of
Electrical Parts List
SECTION 7 DIAGRAMS
AND MECHANICAL PARTS ILLUSTRATIONS
Diagrams
Mechanical Parts Illustrations
SECTION 8 MECHANICAL
PARTS LIST
Mechanical
Parts List Information
Index of
Mechanical Parts Illustrations
Mechanical Parts List
Accessories

Intro d uction
© A
S
E CTIO N 1
7 Β 70
S PE CI F I CA ΤΙΟ
Ν
C h ange info r mation, if any, affecting t h is sectio n will b e found at t he r ear of t h e m αηυαΙ .
The 71370 Time Base
U nit is designed specifically fo r use
with Te k t r onix 7700-se
r
ies oscillosco
p
es .
However, it is
com p ati b le wit h all 7000-series oscillosco p es . T he 71370
p rovi d es cali b rate d swee p s from 5 secon d s/ d ivision to 0 .02
microsecond / d ivision . T he Χ 10 M AG N I F I ER exten d s t h e
cali b rate d sweep to 2 nanosecon d s/divisio n . Swee p rates
may b e varie d continuously (u n cali b rate d ) between cali b ra-
te d ste p s . Swee p trigge r ing is to 200 mega h e r tz or ve r tical
.am p lifier b andwi d t h , w h ic h ever is less . T h e 71370 featu r es
an
external h orizontal am p lifie r to display sig n als applie d to
TA BLE 1-1
ELE CT R ICA LC HA R ACT ER ISTICS
ί
7 Β
70
t h e ΕΧΤ V O L TS IN co nn ector . T h e swee p free- runs to p ro-
vi d eα b rig h t b ase line in t he a b senceof ade q uate triggeri n g
sig n al in Ρ - Ρ A U TO an d AU TO trigge r i ng mo d es .
T h ePerformance C h ec k P r ι ce du re give n in Section 5
provi d es α convenient met hod of c h ec k ing performance of
t h is i n str u ment . T he following electrical ch aracteristics
apply at an am b ient tem p eratu r e of 0 ° C to +50 °
C,
un
less
ot
h erwise note d . W armu ptime
for
give
n accu r acy is 20
mi n utes .
C h aracte r istic Performan ce
E xclu de Following Start of Swee
p ; 50 ns
P ortio n s of Magni-
fie d Swee p End of Swee p ;
beyon d 100 d ivisions
Swee p L en gt h 10 .0 d ivisio n s
to 13 d ivisio n s .
Sweep H ol d -Off Time
5 s/ d iv to 5 μ s/ d iv 1 .5 times t he TIME/DIVISION set-
ting or less .
2 μ s/ d iv to 3 .5 microseconds or less .
0 .02 μ s/div
External H o r izontal
Amplifier
Deflection Factor
ΕΧΤ
VA R IA BLE 25 millivolts/ d ivisio n with in 5 milli-
F ully Cloc k -
volts/ d ivisio n .
wise
ΕΧΤ = 10
VA R IA BLE 250 millivolts/
d ivision with i n 50
Fu lly Cloc k - millivolts/divisio
n .
wise
VA R IA BLE
At least 10 :1
R ange
C h
aracteristic Perfo r ma n ce
Swee pR ate
Calibrate dR ange 5 secon
d s/division to 0 .02 micro-
secon
d/d ivision in α 1-2-5 se quen ce .
Χ 10 mag
n ifier extends swee p rate
to 2 nanosecond
s/divisio n .
VA R IA BLE R ange Co n tin u ously va
r
ia
b
le
b etween cali-
(uncalibrated) b rated sweep r ates . Exten
d
s un
cali-
br ate d swee p r ate to at least
12
.5
secon d s/ d ivision .
Sweep
Accu r acy M easure d in 7700-series
mainframe .
Time Interval
+15
°
C
to
+35
°
C 0 ° C to +50 ° C
Ove
r Center 8 U nmag
M ag U nmag M ag
d
iv
5
s/
d iv to 0 .1
s/div and0 .2 3%
3 .5% 4% 5%
μ s/div to 0 .02
μ s/div
50
ms/div to
2% 2 .5% 3% 4%
0 .5 μ s/ d iv
Over any 2 div
interval with i n 5% 7%
ce n ter 8 div

Specification-71370
T h is
instrument will meet t he electr ical c h a
r
acter
istics
given
in Table 1-1 over t he following environme
n tal
limits .
Altitude
Non-operating
F inis h
Dimensions
W eig h t
TA BLE 1-2
ENV
I R O NMEN TA LC HAR ACT ER ISTICS
C h aracteristic
C h aracte r istic
TA BLE 1-1 (cont)
P
e r fo r mance
To 50,000 feet and -55 ° C .
TA BLE 1-3
PH YSICA LC HA R ACT
ER ISTICS
P erformance
F ront panel is ano
d ize d aluminum .
14 .583 inc h es lo n g by 2 .75 inc
h
es
wi d e b y 5 inc h es h ig h .
Ap p roximately 2 .88 p ounds .
C h aracte r istic
Pe r formance
E xte r nal T r igger Input
M aximum In p ut 500 volts
(DC
+P
ea k AC) . 500
V
oltage volts (P-
Ρ
AC)
at 1 k ilo h ertz or less .
Input R and C 1 mego
h m with in 2°/ ο , 20 picofarads
with
in 2p icofa r ads .
L evel R an ge
( E xcl ud ing
Ρ - Ρ
A U TO)
ΕΧΤ At
least +1 .5 volts to -1 .5 volts .
ΕΧΤ
_
10
At least +15 volts to -15
volts .
Ρ - Ρ A U TO
Operation
Sensitivity
0 .5 div Internal, 125
millivolts Ex-
ternal, 200 Hz to 20 MHz .
Upp er
fre qu ency andamplitude
limits
same as N O RM A L T r igger
Sensiti-
vity .
L ow F re q uency
Mu
st
T r igge r on 50 h ertz, 2d ivision
R espon se sig n al
.
TA BLE
1-1 (cont)
C ha r acteristic
Performance
Frequency
System -3 d B p oi n ts in 7700-series
R esponse
oscillosco pe .
L ower -3
d B U pper -3 d B
AC, AC LF REJ, 16
h ertz 100 k ilo h ertz
AC HF REJ
DC
-----
100 k ilo h ertz
Trigge r Sensitivity
Triggering M inimum
Trig-
F re q ue ncy gering Signal
R ange' R e q uired
Cou p
ling
ΙΝΤ ΕΧΤ
AC 30 Hz
to 20 MHz 0 .3 div 75
mV
20 MHz to
1 .5 d iv 375 mV
200 MH z
AC
LF REJ 2 30 kH z to
0 .3 div 75 m V
20 MHz
20 MHz to
1 .5 div
275 m V
200 M H z
ACHF
REJ 30 H z to 50
kH z 0 .3 d iv 75 m V
DC DC
to 20 MH z 0 .3 d iv 75
m V
20 MH zto
1 .5 div 375 mV
200 MHz
'On
I n ter n al Triggering Only ; the
specified u p p er -3 d B fre q uency
of t h e V ertical System re p laces
upp er limit frequencies in t
h
e
a b ove table w
hen t he nu mber in
t he ta b le is greater t h an t he -3 d B
fre quen cy of the V ertical System .
Ζ W ill not trigger on sine waves of 3
divisions or less internal or 1 .5
volts external below 120 Hz .
Single Swee p Triggering re q
uirements same αε
normal sweep .
Wh en triggere d ,
swee p generator
p r oduces οηε
sweep only .
Internal Trigge r J itte
r 1 nanosecon d or less at 150 mega
h ertz .

General
S
E CTIO N 2
OPERATING
INSTRUCTIONS
Ch ange information, if an y , affecting t h is
section will
be found
at
t he rear of t
h e manual .
T he 71370 p
lug-in unit op erates with α Te
ktronix
7000-series in d
icator oscilloscope andα 7A-series
vertical
p lug-in unit to
form α com p lete oscillosco p e
system .
To
effectively
use t he 71370 its op eratio n
and ca p abilities
s h ould be k nown . T h is section d escribes
t he op eration of
t he front- p anel controls, gives first-time
an d general op era-
ting informatio n an d lists some
basic app licatio n s for t h is
instrument .
Installation
T he
71370
is designe dto o p erate in t he horizo n
tal p lug-in
com p artments
of Te k troni x7000-series oscillosco p es
. T h
e
71370
can also be i n stalle d in α vertical p lug-in
com p artment
to p rovi de α swee p t h at runs vertically on
t he CR T . How-
ever,
w h en used in t h is manner, t h ere is no
retrace blank ing
or
internal triggering p rovision and t he unit m ay
not m eet
t
h
es
p ecifications given in Section 1 . T h e instructions
in
t h is manual are written for use of t he 71370 in αh
orizontal
p
lug-in com p
artme n t of t h e oscillosco pe .
Wh en t h
e
71370
is used wit h an oscillosco p e w h ic
h h as
two h
orizontal p lug-in co mp artments, install t h is unit
in t he
Β (rig h t) com p artment . T hen, if αd elaying-swee punit
is
installe
d
-in t he Α (D EL AYI NG TIME B AS E ) com p
art
m
ent,
d elayed -swee pop
eration is available . T h e 71370 will op
erate
F ig . 2-1 . L ocatio n of
r
elease
latc h .
O p erating Instructions-71370
p rop erly in t he Α com p artment for all h orizontal mo d es of
o p eration exce p t delaying swee p .
To
install t he
71370
into α p lug-in com p artment, push it
in until it fits firmly into t he in d icator p lug-in com p art-
ment . To remove, pull t he release latc h (see F ig . 2-1) to
disengage t h e unit from t h e in d icato r an d pull it out of t h e
plug-in com p art m ent . E ve n t
h
oug
h
t h e
horizon
tal gain of
t
h
e in
d
icator oscillosco pe is
stan d
ar
d
ize
d
to minimize a
d -
j ustment
w
hen inserting p lug-in units, t h
e
s w
eep
calibration
of t h e 71370 s h ould be c h eck ed w hen it is inserted into t h e
indicator to verify measure m ent accuracy . T he procedure
for c hecking t h e unit is give n under Swee pCalibration
C heck in t h is section .
General
Triggering
Controls
L E VEL /S L O PE
T R IG'D
F R ON T- P AN EL CON TR O L S
All controls re q uire dfor t he o p eration of t h e 71370 are
locate
d on t h e
fro nt p anel of th e un it (see F ig . 2-2) .
To
ma ke full use of t h e cap abilities of t h is instrument,
t h
e
op erator s h ould be familiar with t he f unction an
d
use of
each of t hese controls . Α brief d escri p tion of t he front-
pan el controls an d connector is gi v en h ere . M ore detaile d
information is given un d er General O p erating Information .
Selects t h e am p litude point an d
slo pe of
trigger signal on w h ic h t he
swee
p is
triggere
d . Wh en t he in d ica-
tor line
on
t he outer ring
is to
t he
left of center, t h
e swee p
is triggere d
on t h e p ositive-going slo p e of t he
trigger signal, as s h own by t he
positive-going waveform . To t he
rig h t of center, t h e sweep is trig-
gere d on t he negative-going slo pe of
t he trigger signal as s h
own by t he
negative-going waveform .
L ig h t in d icates t h at t he
swee p
is
triggere d an d will p ro d uce α
d
is p lay
wit h correct setting of t he POSI-
TION
control an
d
t hecontrols on
t he associate d vertical unit and indi-
cator oscillosco pe .

O p
erating
Instructions-71370
M
OD
E
2-2
Se
r ies of push -button
switc h es t6
select t h e trigger mo d e .
Selecte d
mo de
is indicate d by
lig h ted b ut-
ton .
Ρ -
Ρ A U TO : Sweep
automatically
triggere d at point selecte dby the
LEVEL/SLOPE con
trol w hen
t he trigger signal re p
etition rate
is above about
200 hertz an d
wit h in t h e freq
uency range selec-
ted by t h
e
CO
UPL I N G switc h .
Triggered
sweep can b e obtaine d
t h roug h out t
h
e
entire range of
t h e LEVEL /S
L O PE control
.
Wh e n t
h
e
trigger rep etition rate
is below t h e lower fre q uency
limit (or above u p p er
limit for
ACHF REJ)
or
w
h en t he trigger
signal is ina d eq
uate, t he sweep
free runs at
the sweep rate selec
ted b y
t he ΤΙΜΕ /DI V switc h to
produce
α
reference
trace .
AU TO :
Sweep initiate d by
t he
a pp lied
trigger signal at p
oint
selected b y t h e LEVEL /S L O
PE
control w h en t he trigger
signal
repetition rate is above about
30
h ertz and with in t he fre q
uency
r ange selecte dby t
he
CO
U -
PL I N G switc h . Triggere d
sweep
can b e o b taine d only over
t he
am p litude range of t he a p p
lie d
trigger signal . Wh en t he LEVEL /
SL O PE control is outsi d e t he
am p litude range, t he trigger r ep -
etition rate is below t he lower
fre q uency limit (or a b ove u pp er
limit for AC HF REJ) or t he
trigger signal is ina dequ ate, t he
sweep
free runs at t h e sweep rate
selecte d b y the ΤΙΜΕ /DI V
switc h to produce α reference
trace .
N O RM :
Swee p initiate d by th e
ap p
lie d trigger signal at any
p oi n t selecte d by t he LEVEL /
SL O PE control over t h e fre qu
en-
, . γ range selecte d by t he CO U -
PL I NG switc h . T r iggered swee p
can be obtained only over
the
amplitu de range of t
heapp lie d
t r igger signal . Wh en
t he LEVEL
/
SL O PE control
is outsi d e the
am p litu d e r ange,
t he t r igger re p -
etition rate
is outsi d e t h e fre-
q uency range selected b y t he
CO UPL I N G switc h or t he
trigger
CO UPL
I NG
signal is inade q uate, t h ere is no
trace .
SI N G LE S WP : Sweep
initiated b y
t he app lie d trigger signal
at
any
p oint selected by
t he LEVEL
/
SL O PE control over
t he fre-
q uency range
selecte dby t h e
CO UPL I NG
switc h . Triggere d
swee p can be
obtai n
e
donly over
t h e am p litu d e
range of ap p lie d
trigger signal
. After t h e first
swee p is
dis p layed, furt h er
swee p scannot
be p resented until
t h e RE S E
T- RE ADY p us h -
button is p
r
essed .
Wh
en
t h e
LEVEL /S L O PE
control is out-
si d e t h e am p
litude r ange, t h e
trigger r e p
etition rate is outsi de
t he frequency
range selected by
t
he
CO
UPL I NG switc h , t he trig-
ger signal is
inade
q
uate or w h en
t he RE SE T- RE
ADY lig ht is off,
t
h
ere
is
no
trace .
RE S ET- RE ADY : Pu s h -button
to
reset t he Sweep Generator
for
t h e next sweep
i n t he si n
gle-
swee p mo
d
e .
T h e
RESET-
READY button remain s lig h te d
to indicate t h at t he unit is r ea dy
to be triggere d . After t he unit is
triggered andα swee p is com-
plete d , t he RE SE T- RE ADY
lig h t
goes out until
t hebutton is
p ressed again .
Series
of p us h -button switc h es to
select t he trigger
cou p ling . Selected
coupling
is indicated b y lig h te d
button .
AC : Re j ects DC a nd attenuates
AC
signals b elow about 30
h
ertz
.
Acce p
ts signals between 30 h ertz
and 200 mega h ertz .
AC LF
REJ : Re j ects DC an d atten-
AC
HF REJ : Acce p ts sig n als be-
tween about
30 h ertz an d50
kilo h ertz . Re j ects DC an d atten-
uates signals ou tsi d e t
h is fre-
quen cy range .
uates
signals below a b out 30
k ilo h
ertz
. Acce p ts signals be-
tween 30 k ilo h ertz an d
200
mega he r tz .

SO UR C E
Α
Fig .
2-2
. Fro n t- P a n el co n trols and con n ectors .
DC : Acce p ts al
Ι trigger signals from
DC to
200 mega h ertz .
Series of push -button
switch es to
select t he trigger
source . Selecte d
source is
in
d
icate d by lig h te d
but-
ton .
ΙΝΤ :
Trigger signal obtaine d inter-
nally
from α vertical unit .
L
I NE : Trigger signal
obtaine d in-
ternally from α
sam
p
le of t he
O p
erating Instructions-71370
SWEEP
CONTROLS
line voltage ap plie d to th is in-
strument .
ΕΧΤ :
Trigger signal obtaine d from
an external signal a p p lie d to t he
ΕΧΤ T R Ι G IN connector .
ΕΧΤ
-
10 : Trigger
signal obtained
from an external signal
ap p lie d
to t he ΕΧΤ T RIG IN
connector
as in t he
ΕΧΤ p osition . In t h is
p
osition t h e external sig n al is
2- 3

Operating Instructions-71370
ΕΧΤ T R
IG IN or

Ιηρυτ con nector for external trigger
ΕΧΤ V
O
L TS
IN

signal
or am p lifier in p ut signal .
Swee p Controls
P OSITIO N
F I NE
ΤΙΜΕ /DI V
V A R IA BLE
( ΤΙΜΕ /DI V
)
M AG N I F I ED
S WP CA L
2- 4
attenuate d 10 ti m es before it is
a p p lied to t he trigger circuit .
Controls h orizontal p osition of
dis-
play .
P rovi d es more precise control of
h orizontal positions .
Selects t he b asic sweep rate of t he
out p u t sawtooth . T he V A R IA BLE
control m u st be in cali b rated p osi-
tion an d M AG N Ι F Ι E D switc h set to
Χ 1 for indicated swee p rate .
Two-position switc h actuated by
t h e V A R IA BLE kn ob to select cali-
brate d or uncalibrated swee p rates .
At t he in p osition, t he V A R IA BLE
cont r ol is ino p erative and t he swee p
rate is calibrate d . Wh en pr esse d an d
release d , t he k nob moves out to
activate t he V A R IA BLE cont r ol fo r
uncalibrate d swee p r ates . T he
swee p rate in eac h ΤΙΜΕ /DI V
switc h p osition can be re d uce d to
at least t h e swee p rate of t he next
a dj acent position, to p rovi d e con-
tinuously
va r iable sweep rates from
2
nanosecon d s/ d ivision ( Χ 10- M AG-
Ν Ι F Ι ΕR on) to about 12 .5 secon d s/
division, wit h M AG N I F I ER at Χ 1 .
P us h -button switc h es to select t he
h orizontal magnification . T h e
Selecte d mag n ification is indicate d
byα lig h
ted bu tton .
X1 : M agnifie d
swee p
at t h
e
basic
sweep
rate in
d icate d by TIME/
DI V switc h .
Χ 10 : M agnified sweep at α swee p
rate
10 times faster than the
b asic
sweep rate
in
d icate d by the
ΤΙΜΕ /DI V switc h . T he
portion
of
t h
e n ormal sweep with in the
center d ivisio n of t he graticule is
t he
po r tion s h own in magnifie d
form .
Screw d river a
d j
ustment
to
set a
m -
plitu
d
e
of
t
h e
out p ut
sawtoot h .
Dis play M o d e
TIME B AS E Selects sweep rates as determine d
by ΤΙΜΕ /DI V switc h .
A MPL I F I ER

Dis p lays signals app lie d to t h e ΕΧΤ
TR IG IN or ΕΧΤ V O L TS IN connec-
tor . Select TR IGG ER I NG SOUR CE
an d CO UPL I NG .
V A R IA BLE

V aries deflectio n factor byα facto r
(am p lifier)

of 10 .
General
F ig . 2-3 s h ows the front p anel of the 71370 . T h is c h art
can be repro d uce d and u sed as α test-setu p r eco r d for
special measurements, a pp lications or proce d ures, or it may
be u se d as α training ai d for familiarization wit h t h is i n st ru -
ment .
G ENER A L O PER ATI NG I NF O RM ATION
Swee p Calibration C h ec k
T E ST SE T UP C H A RT
Wh enever t he 71370 is inserte d into α plug-in compart-
ment ot he r t han t he one in w h ic h it was calibrate d , t he
swee p calibration s h oul d be ch ec ke d an d rea d j usted if nec-
essary . Allow five minutes warmu pb efore p erforming t h is
p roce d ure .
1 . Connect α one- k ilo h ertz cali b rator signal from t h e
Indicator Oscillosco p e Cali b rator to t he V ertical unit i npu t
con nector .
2 . Set t he
TI
ΜΕ /DI V switc h to 1 ms a n d press t heto p
TR IGG ER I N G a nd DIS PL AY M OD E pus hbu tto n s .
3 .

Set t he V ertical unit to dis p lay at least two d ivisions
of
t
h e sig
n
al
vertically .
4 . C h ec k t he C RT
dis p lay for one com p lete cycle p er
d ivision .
5 . If necessary, ad j
ust t he
S
WPCA L a dj ustment for one
com p lete cycle p er division .
Sim p
lifie d Op erating Instructions
T he following
information is p rovi d ed to ai d i nq uic k ly
ob
taining
t he correct settings for t he 71370 to p resent α

7B70 TEST SET-UP
CHART
2-5

Operati ng
Instructions-71370
d is p lay . T he op erator
s h ould b e familiar wit h t he com p lete
functio
nand operation of the unit as d escri bed in t
h
is sec-
tion before using t h is p roce d ure .
Normal Swee p . T he following p roce d ure will p rovide
α
sta b le d is p lay fo r most normal-sweep applications .
1 .
Select
t he T R
IGG
ER I NG M
OD
E , CO UPL I NG a nd
SO UR CE
w
h ic h fit
t
h e re q
uirements of t he signal to be
d is p layed .
2 . Turn
t h
e
LEVEL /S L
O
PE control to t he d esi r e d
slo pe
.
3 . If t h e green T R IG'D lig h t is not on, ad j ust t h e
LEVEL
/S
L O PE control t h ro ughout t he range of t he selec-
te d slope u ntil t he T R IG'D lig h t comes on . If t he lig h t d oes
not come on at any setting of the LEVEL /S L O PE con t r ol,
t he trigger signal is ina deq uate or t he CO UPL I N G and
SO UR C E switc h es are set incorrectly .
4 . Set t h e ΤΙΜΕ /DI V switc h a nd P OSITIO N control for
α dis p lay w h ic h remains on t he d isplay area h orizontally
(V A RIA BLE control s h ould be i n CA L p
osition for cali b ra-
te dsweep rates) .
5 . If t he dis p lay does not start at t he correct p oint on
t h e waveform, rea d ju st t h e LEVEL /S L O PE control for t he
d esire d triggering .
M agnified Sweep . Α magnified-sweep d isplay can be
o b -
tained as follows after αnormal-sweepd is p lay is obtaine d as
given i n ste p s 1-5 above .
1 .
A d j ust
t
h e
P
OSITIO
N
co
n trol to move t he area to be
magnified wit h i
n t
he ce
n
ter
divisio n of t h e C R T .
2 .
If
necessary, c
ha n ge t h e ΤΙΜΕ /DI V switc h setti n g so
t h
e com p lete area
to
be
magnifie d is wit h in t he ce n ter d ivi-
sion .
3 . P ress t he X10- M AG Ν 1 F ΙΕ Rp ush -button .
4 . U se t h e fi n e range of t he P OSITIO N con trol to esta b -
lis h p recise p ositioning of t h e magnifie d d is p lay .
Delaye d Swee p . T h e following p
roce d u r e can be used to
obtain α delaye d -swee p d isplay w hen t h e 71370 is
used in
an
2-6
oscillosco pe t h at h as du al time b ase
capabilities a n d w h en
used wit hα com p anio nd
elaying-swee p unit ( Α )
.
Obtain α
d is p lay as
given in ste p s 1-5 und er Normal Swee p . T hen
p roceed as follows :
1 . P ress t he Β STA R TS A F T ER D EL
AY p us h -butto n
on the Α time-base .
2 . Set t h e i n dicator oscillosco p e horizo n tal mo de to dis-
play t he Α time b ase .
3 . Set t h e ΤΙΜΕ /DI V switc h
of t h e
71370
so t he intensi-
fied zone on t he dis p lay is t he desi
re
d
lengt
h (i
n tensifie
d
zone will b e d is p laye d in d elaye d form) . If t h e i n te n sifie d
zon e is n ot visible, a dj ust t he i nd icator inte n sity co n
trols
.
4 . A d ju st t h e Α
time- b ase D EL AY TIME MUL T d ial to
p ositio n t h e inte n sified zo
n e
to
t
he p ortion of
t he d is p lay
to bed elaye d .
5 . Set t he i n d icato
r oscillosco pe h orizontal mo d e to
dis-
play t he Βtime base
(7
Β
70) .
6 .

If α d elayed swee pwith less j itter is desire d , p ress t he
Α time-base ΒT R IGG ER A BLE A F T ER D EL AY p us h -
button . T he triggeri ng con trols of t he 71370 must be set to
obtain α sta b le d is p lay .
P us h button Switc h L ogic
T he T R IGG ER I N G M OD E , CO UPL I N G an d SO UR C E
switc h es and t he DIS PL AY M OD E switc h are arrange d i nα
se q uence w h ic h p laces t he most often-used p ositio n at t he
top of eac h series of p us hb uttons . W it h t h is arra ngement, α
stable normal-sweep d is p lay can usually be obtaine dby
pressing t he top p u s h -buttons ; Ρ - Ρ A U TO, AC, ΙΝΤ an d
TIME B AS E . Wh en an ad e q uate
trigger signal is a p plie d , t he
un
it is triggere d as in d icated by t he illuminate d T R IG'D
lig
h t at
any setting of t he LEVEL /S L O PE control . If t he
TR
IG'D
lig h t is not on, eit h er t he trigger sig n al ap p lie d to
t h is unit from t h e vertical unit is ina deq uate or it is b elow
t h e lower fre q uency limit of t he ACCO UPL I NG switc h
p ositio n . If t h e desired dis p lay is not o b tained wit h t he
push buttons p us h ed in, ot h er selections must be ma de .
R efer to t he followi n g discussio n s or t he instruction
ma n uals for t he associated in d icator oscilloscope and verti-
cal
unit for more information .
Triggered L ig h t
T he T R IG'D lig h t p rovi d es α conve n ie n t in d icatio n of
t he con d itio n of t h e triggering circ u its . If t he T R IG-
G ER I N G controls are correctly set and an a d e qu ate trigge r

F
ig
.
2-4
.
V iew of fro n
t
pan el s howin g p u s h - bu
tto
n s associate d
wit
h
t h e
M
OD
E ,
CO UPL
I NG
an d SOUR C
E
switc
h
es .
signal is app lie d ,
t
h e
T R
IG'D
lig h t is
on
. Un d er certain
co nd
itions, t he T R IG'D lig h t may be off, in d icati ng t h at
t h e swee p is not triggere d . T h e cause mig h t be
α misa
d -
j uste d LEVEL /S L O PE control,
incorrectly set CO UPL I N G
or SO URC E switc h es, low
trigger signal am p litu d e, or α
trigger signal re p etitio n rate outsi de t he accep table fre-
q uency range . T h is feature can be used as α general
in
d ica-
tion of correct triggering . It is p articularly
useful w he n
setting up t h e trigger
circuits w hen α trigger signal is avail-
able with out α d is p lay on t h e C R T . It also in d icates t h at
t h is unit is correctly triggere d w hen op erating as αdelayed -
swee punit ( Β ) .
Trigger M od e
O p erating
Instructions-71370
T he pus h buttons locate d under
t h
e
M
OD
E title (see F ig .
2-4) select t h e mo de in w h ic h t
h
e swee p is
triggere
d .
T h
e
selecte d mo de is i n d icate dby α lig h te d push button .
Ρ - Ρ AUTO . Wh
en
t heΡ
- Ρ
A U TO
push button is p resse d ,
α triggere d d is p lay is p rovi d e d at any
setti n g of t he LEVEL /
S L O PE
control
w
h
enever an a
d eq uate trigger signal is
ap p
lie d . T
he range of t he LEVEL /S L O PE control in t h is
mo de is b etween about 10% and 90% of t he peak -to- peak
am p litu de of t h e app lie d trigger signal . T he LEVEL /S L O PE
control can
be
set
so
t hed is p laye
d
waveform starts at
any
p oint with in t h is range
on
eit h er slo pe . In t h e Ρ - Ρ A U TO
mo d e, t h e trigger circuit automatically com pensates for
ch anges in trigger signal am p litude for sig n als above t he
minimum am p litu d e re q uirement . T h erefore, if t h e LEVEL /
SL O PEcontrol is set so t he d is p laye d waveform starts at α
certain p ercentage- point on t h e leading edge of α low-
amplitude signal, it triggers at t h e same p ercentage- point on
t he lea d ing e d ge of α h ig h -am p litu de signal if t h e LEVEL /
S L O PE control is not ch ange d . T h is op eration is illustrate d
in F ig . 2-5 .
Wh en t he trigger repetitio n rate is below about 200 h ertz
(or outsi de t he fre q uency range selected by
t h
e CO
UPL I NG
switch ), or w hen
t he trigger signal is inadeq uate, t h e swee p
free runs at t he swee p rate indicated by the TIME/DIV
switch to p ro d uce αreference
trace (T R
IG'D
lig h t off) .
Wh en an a d
e quate trigger signal is again app lied, t he free-
running con d ition en d s and α triggered d is p lay is p resente d .
T h e Ρ - Ρ A U TO trigger mo de is p articularly useful w hen
ob serving α series of waveforms, since it is not necessary to
reset t he LEVEL
/S
L O PE control for each observation .
Also, because of t h e ease of obtaining α triggere d d is p lay in
F ig
.
2-5
.
LEVEL /S L O
PE
control o p eration
for (P-P) AU
TO mo d e
triggeri n g
. (
Α ) LEVEL /S L
O
PE
control
set so d is p laye dwavefor m starts at
a bou t 25% poi n t of α two-d ivisio n waveform .
(
Β
)
d is p laye d waveform still triggere d at a bou t 25% of lea d i ng e d ge, w h en sig n al amplit ud e
i n
creases to p ro d
u ce α
six-division
d is p lay (LEVEL /S L O PE
co
n trol at sa m e setting for bot h waveforms)
.

O p erating
Instructions-71370
t h is
mo d e, t heΡ - Ρ AUTO
trigger mo de can be use d
for
most a pp lications an d t h e
remaining mo d es used only for
s p ecial a pp lications or w
h en stable triggering is not
obtain-
able in t h is mode .
A UTO . Wh en t he A U TO push
-button is illuminate
d , α
triggere d d is p lay is presented
wit h t h e correct setting
of t he
LEVEL /S L O
PE control (see Trigger L evel
discussion)
w h enever an
a de q uate trigger signal is a pp
lie d . T he range of
t h e LEVEL /S L O PE
control in th is mode is ±8 vertical d ivi-
sions . T he T
R
IG'D
lig h t in d icates w hen t he dis p lay is
trig-
gered .
Wh en the
trigger re p etition rate is below a b out 30 h ertz
(or outsi de t h
e fre
q
uency ra nge selecte d by t he CO UPL
I
N G
switc h ) or
w hen the trigger signal is ina d e q uate,
t h
e
swee p
free runs at t h e swee p rate indicate d by
t he ΤΙΜΕ /DI V
switc hto p roduce α reference trace (T
R
IG'D
lig h t off) .
Wh en an a de q uate trigger signal
is again a pp lie d , t h e free-
run n ing con d ition en d s an dα
triggere
d
dis p lay is p resente d .
Wh en t h e LEVEL /S L O PE control is at α
setting outsi de t he
am p litude range of t he trigger signal, t h e
sweep also free
runs at t he swee p rate indicate d by
t h
e
ΤΙΜΕ /DI V switc h .
T h is type of free-running d is p lay can
be useful w hen it is
d esire d to measure only the maximum
p eak -to- pea k am p li-
tu de of α signal wit h out observing t h
e waves h a p e (such as in
ban d wi d t h measurements) .
N O RM . Wh en t he N O
RM pus h - b utton is p resse d , α trig-
gered d is p lay is p rese nted with
t h e correct setting of t he
LEVEL /S L O PE control w h
enever an ad
e q
uate trigger signal
is a pp lie d . T he ra n ge of t
he LEVEL /S L O PE control in t h is
mode
is ±8 vertical divisions . T h e
T R
IG'D
lig h t in d icates
w hen the d is p lay is triggere d .
T h
e
N O RM
trigger mo de must be used to p ro d uce trig-
gere d dis p lays
wit h trigger repetition rates belowabout 30
h ertz . Wh en th e LEVEL /S L O PE control is at α
setting out-
si de t he am p litu de range of t he
trigger signal, w h en t he
trigger re p etition
rate is outside t he fre q uency range
selected b y t he CO UPL I N G switc hor w hen t he trigger sig-
nal is ina de q uate, th ere is no trace (T R 1G'D lig h
t off) .
SI N G LE S
WP . Wh en t h e signal to be d is played
is not
re p etitive or
varies in am p litude, waves hape or
re p etition
rate, α
conventional re p etitive typ e d is p lay may p
rod uce
an
unstable p
resentation . Α stable dis p lay can
often be o b -
taine d
under t hese circumstances by usi n g
t he single-swee p
feature of
t h is unit . T he SI N G LE S WP M OD E is
also useful
to p h otogra
p h non-repetitive or u n stable dis p lays .
To obtain
α single-sweep d is p lay of αre p etitive
signal,
first
o b
tain t h e best possi b le d is p lay in t heN O RM
M
OD
E .
T h en wit h out ch anging t he oth er TR IGG ER
I N
G
controls,
2- 8
p ress t he SI N G LE S WP
push button . Wh en rea dy to view
th e single-swee p d is p lay, p
ress th e RE SET- RE ADY push -
b utton . Α single
trace is p resente d each time th e RE S ET-
RE ADY pus h button
is p resse d (as long as t he re p etitive
sig n al remains connected
to t he system and T R IGG ER I N G
controls are correctly set)
and furth er swee p s cannot b e
p
resente d u
n til t h e RE S ET- RE ADY push button is p resse d
again . If th e dis played signal is α com p lex waveform
com pose d of p ulses of varying am p litude, successive single-
swee p d is p lays may not start at t he same point of t he wave-
form . To avoi d confusion d ue to
t h e CR T p ersistence, allow
t he
d
is p
lay
to d ecay before p ressing t h e RE S ET- RE ADY
push button again . At fast swee p rates, it may b e d ifficult to
view t he single-swee p d is p lay . T he a pp are n t trace intensity
canbe
increase d by re d ucing t he ambie n t lig h t level or
usi n gα viewing hoo d as recommen de d in t he i nd icator
instructio n manual .
Non-repetitive, rand om signals can bed is played in t he
single-swee p mo d e by first obtaining t he best p ossible dis-
play in t he N O R M M OD E withα signal w h ic h is about
t he
same am p litude an d fre que n cy as t h e ran d om signal
.
T h en
wit h out ch anging t he oth er T R IGG ER I N G controls, p ress
t he SI N G LE S WP p us h button . Wh en rea dy for t he ran d om
signal, p ress t he RE SET- RE ADY p ush button . T h e RE SET-
RE ADY push button remains lig hted to in d icate t h at t he
unit h as been reset and is rea dy to pro d uce α swee p . T h e
lig h t goes out after t he ran d om signal triggers t h e unit . To
p re p are t he unit for anot h er single-swee p dis p lay, p ress t he
RE S E T- RE ADY pus h button again .
Wh en usi ng the single-swee p mode to ph otogra ph wave-
forms, the graticule must beph otogra ph ed se p
arately in t he
normal manner to prevent over-ex posing
t he film
.
Be sure
t h
e camera system is well
p rotecte
d
against stray lig h t, or
op
erate
t h e
system
in α d
ar
k ene d room .
F or repetitive
waveforms, p ress the RE SE T- RE ADY push button only
once for each waveform unless t h e signal is com p letely
symmetrical . Ot h erwise, multip le waveforms may ap p ear on
t h e film . F or random sig n als, t he camera
lens
can
be left
op
en until th e random signal triggers t he unit ( RE S
ET-
RE ADY pus hbu tton lig h te d ) . F urt h er information on
photogra p h ic tech ni q ues is given in t he camera instruction
ma n
ual
.
Trigger Cou p li n g
T h e push buttons located below t h e
CO
UPL I N
G
title
(see F ig . 2-4) select the met h od in w h ic h t h e trigger signal is
con necte d to t he trigger circuits . T he selecte d cou p ling is
indicate d by α lig h te dpush butto n . E ac h p osition p ermits
selection or re j ectio nof t he fre q ue ncy com p onents of t he
trigger signal w h ic h trigger t he swee p . F ig . 2-6 gra ph ically
illustrates t he ban d of fre q ue n cies covere d by eac h p osition
of t he CO UPL I N G switch .

Operati n g Instructions-7 Β 70
~
" . ϊΣ
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~ D ευ τ1ί ;
= σ ='
τ, Ε, : ί'ε,' :,~ ίί : ωω . :
;:
: έί
__ σ . . . σι , ω . : , σ : . .
__ ω .
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. _ .
_ :- : :ς ~
σσ G :
ο "i σσ , ?
~ : . . λ Φσ
° :
ίΙ ~ σι ~~ ιι
~ ω _ σ : : : σσσι σσ : σ : : : : σσίσσ ;~
__ ω . . . . .~ __ ω _ . .ι _ .
σσ ~C σ : : :σσ σσσ : : : :σσσσσ G~
__ ω _ ισ ~ ωωι _ ωπιιπ _ .
_
ωιιι ι ωωι _ ωιι
~
ισσσ
~ : Γ _ ω _ ιιιι ~_ ωι
=OC ~IlIiI , Ι ~~~ Ι~ ΙΙ ~
== : ι : : ιίι ~ ψ : , ιι σ =
ωσ i :
: ι σΙ ~ ~~ : ίί ::σσι

ί
:
: : ίσ , :~
: : : :
σεΙ
~C
' ω " ϋϋ " ίσί G"i
ιι ~
~ ~~ : : .
~~
~
ε
~,
__ ω . . . ..ι
_~ ω . . . . σι
_

ω . ιιι ι
. . . ι
_ . . .
:
~ ωωι
:
: : σσσ ~=~
: :aii~~ __ ω _ ιιιι
~= σ : : : εεσΙ : σσ : ω : : : :σσ m ~
σ ~ σ ~ σσ ~ σ~ σ : : σι :
~ τ : . : σ σσ :_ : ::σα
L
}ilili G
ε ; ιυ ~ . ; ~ :,
AC
DC

10 Ητ
30 Ητ

ι30 kH z
100 Ητ
50 k H z_

200 ΜΗτ
10 kH z

100 kH z

10
ΜΗτ

100
ΜΗτ
AC . Ιη t he AC p
osition of t h e CO UPL I NG switc h , t he
DC com p onent of
t he trigger signal is b loc ked . Signals wit h
1 οω -fre q uency com ponents
below about 30 hertz are atten-
uate d . Ιη ge
n eral, ACCO UPL I N G ca n b e use d for most
a pp lications . H owever, if t h e signal contains unwante d fre-
q uency
com p onents or if t he sweep is to be triggere d at α
Ιοω re p etition
rate or DC level, one of t h e remaining
CO UPL
I
NG
switc h positions will p rovi de α better d is p lay .
T he triggering p oint
in t he AC position d e pen d s υροη
t h e average voltage
level of t he trigger signal
. If t h
e
trigger
signal occurs
ran d omly, t he average voltage
level will vary,
causing t he
triggering p oint to vary also .
T h is s h ift of t he
triggering p oint may be enoug h so
it is imp ossible to main-
tain α stable d is p lay . Ιη suc h cases,
use DC coup ling .
AC LF REJ . Ιη t h e AC LF REJ
position, DC is re j ecte d
an d 1 οω -fre q uency trigger signals
below about 30 k ilo h ertz
are attenuate d . T h
erefore, t h e sweep is triggere dοηΙγ by
t he hig h er-fre q uency com ponents of the
trigger signal
.
T
h is
p osition is p articularl
y
useful
for providi ng stable triggering
if t h e trigger
signal contains line-fre q uency com p
onents .
Also, t he AC LF REJ
position p rovi d es t he best alter n ate-
mo d e vertical dis p lays at
fast svyee p rates w h en com p
aring
t ωο or more unrelated
signals (wit hd ual-trace v ertical
or
slave d triggering
op eration for d ual-vertical u
n it operation) .
F ig . 2-6 . F re q ue n cy ra n ge of
eac h CO UPL I NG switc h positio n .
AC HF REJ . T h e AC HF REJ position p
asses αΙΙ Ιοω -
fre q uency signals between about 30 hertz an d 50
kilo h ertz .
DC is re j ected and signals outsi d e t he above
range are atten-
uate d . Wh en triggering from com p lex
waveforms, t h is
position is useful for p rovi d ing stable d is p lay
of t he Ιοω -
fre q uency com p onents .
DC . DCCO UPL
I N G can be use d to p rovide stable trig-
gering
wit h 1 οω -fre q
uency signals w h ic h would be atten-
uated
in t he ot h er mo d es, or with Ιοω -re p etitio n rate
signals . It εαη also be use d to trigger t h e sweep w
h e n t h e
trigger signal reac h es α DC level
selecte d by the setting of
t he LEVEL /S L O
PE control . Wh e n using internal triggering,
the setting of t he vertical unit
pos
ί
tio n controls affects t h e
DC triggering p oint .
Trigger Source
T he pus hb uttons locate d b elow
t h
e SOUR
CE title (see
Fig . 2-4) select t he source
of t he trigger signal w h ic h is
connecte d to t he trigger circuits
. T he selected source is indi-
cate d by α lig h ted p us h button
.
σΝΤ . Ιη t he ΙΝΤ position of
t h e
SOUR
CE switc h , t he
trigger sig n al is d erived
from t h e associate d vertical unit,
Furt h er
selection of t he internal trigger signal may be pro-
2-
9

O p erating
Instructions-71370
vi de d by t he associate d vertical unit or i nd icator oscillo-
sco p e ; see t he instructio n ma n uals for t h ese i nstrumen ts for
i n formatio n . F or most a pp licatio n s, t he ΙΝΤ -SO UR CE p osi-
tion can be u se d . However, some app lications requi r e
s p ecial triggering w h ic h cann ot b e obtaine d i n t he ΙΝΤ -
SO UR CE p ositio n . In such cases L I NE- or ΕΧΤ -SO UR C E
must b e use d .
L I NE . T he L I NE p ositio n of t he SOUR C E switc h con-
nects α sam p le of the p ower-li ne voltage, to w h ic h t he i nd i-
cator
oscillosco pe is connecte d , to t h e trigger circuit . L i n e
triggering is
useful w hen t he in p ut sig n al is time- r elated
(multi p
le or su b -multi
p
le) to t he line fre q uency . It is also
useful for p rovidi n g
α stable d is p lay of α li n e-fre quency
compone n t in α com p lex
waveform .
EXT . An external sig n al con nected to t he ΕΧΤ T R IG
IN connector ca n b e used to trigger t h e sweep in t h e ΕΧΤ -
SO
UR C E positio n . T h e external signal must b e time-relate d
to t
he d isplaye d waveform for α stable d is p lay . An external
trigger
sig n al can be use d to pr ovi deα triggered dis p lay
w h
en t he i n ternal sig n al is too low in am p litude for correct
triggeri
ng or con tains sig n al com p onents on w h ic h it is not
d esired to trigger .
It is also usef u l w hen signal tracing i n
amplifiers, ph ase-s h ift
network s, wave-s hap ing circ u its, etc .
T he sig n al from
α si
n
gle
point
i n t he circuit unde r test can
b e co nn
ected to t he ΕΧΤ T R IG IN co nn ector t h roug hα
p robe o r
ca b le . T he sweep is t hen triggered by t he same
signal at
all timesand allows am p litu d e, time relatio n s h ip or
waves h ape
ch anges of signals at vario u s p oints in t he circuit
to b e exami ned wit
hout resetting t he TR IGG ER I NG con-
trols .
ΕΧΤ
-
10 . Operatio n i n t he ΕΧΤ
_
10 p osition is t he
same as d escribe d for ΕΧΤ exce p t t h at t he external signal is
atte nu ate d 10 times . Atten uation of hig h -am p litu de
exter-
nal tr igger signals is d esira b le to b roa d en the range of the
LEVEL
/S L O PE con trol .
Trigger Slo p e
Th e LEVEL /S L O PE control determi
n es w h et h er t he
trigge r circuit res pon d s on t h
e
positive-going
or n egative-
going p ortio n of t he trigger sig n al
.
Wh en t
he indicator li ne
on t h e outer ri ng of t he LEVEL /S L O PE
control is to the
left of center, t he d isplay starts on
t he positive-going p or-
tio n of the wavefo
r
m
(notice p ositive-goi ng waveform to
left of control .
To
t he rig h t of ce n ter, t he dis p lay starts on
t
he
negative-going p ortion o f t he waveform (notice
negative-goi ng wavefo r m) . T he effect of t he LEVEL
/
SL O PE control
on the
dis p layed waveform is s h ow n i n F ig .
2-7 . Wh en seve r al cycles of α signal a pp ear i n t he d is p lay,
t he selectio n of t he trigger slo p e is often unim p ortant .
H oweve r , if
only
α ce r tain p ortio n of α cycle is to be dis-
p laye d , correct setti ng of t h e LEVEL
/S L O
PE control
is
im p orta n t to pr ovi de α d isplay w h ic h starts
on
t he d esired
slo p e of t h e input signal .
2-
1 0
Trigger
L
evel
T he LEVEL
/S L O PE con trol determi n es t he voltage level
on t h e trigger signal at w h
ic
h
t he d is p lay is triggere d , as well
as selecti ng t he trigger
slo p e . T he center kno b of t he
LEVEL
/S
L
O
PE
con
trol p
rovi d es ab o u tα 3 :1 reductio n i n
relatio n to t he outer in d icator ring,
to allow p recise level
selection . T h is con trol can also b e t
u rned
t h
ro u ghout t he
complete 360 ° rotation to allow co n tinuous tr iggering
over
t he
selecte d slo p e . T h is is p articularly useful i n t he Ρ - Ρ
AU
TO
M
OD
E .
Wh en t he LEVEL /S L O PE control is set to
t he " Ο "
on
eit he r t he p
ositive-goi ng or n egative-goi ngwave-
form, the sweep is triggere d n ear
t he ze r o-volt level of t he
trigge r signal . As t he LEVEL /S
L O PE con trol is r otate d
away from t he " Ο ", t he d is p
laye d waveform starts at α
p oint corres pond i ng to t he p ositio nof the
i nd icator line on
t h e associated slo pe waveform (wit h i n
am p
litu
d e range of
trigger
signal except in Ρ - Ρ A U TO M OD E w h
ic
h p
rovi d es
triggere
dd is p lay t hrough out enti r e slo p e) . F o r exam
p le
if
t he
LEVEL /S L O PE control is turne d cloc k
wise
from t
h
e
" Ο " on t he p ositive-going slope, t he d isplayed
waveform
starts at α mo r e p ositive level . F ig . 2-7 illustrates
t he op era-
tio
n of t he LEVEL /S L O PE con trol at d iffere n
t levels a nd
slopes of αd is p laye d waveform .
B efore setti ng t he triggering level, select t
h e T R IG-
G ER I N G SL O PE, M OD E , CO UPL I N G an d
SO
UR CE .
T he n
ad j ust t he LEVEL /S L O PE control so t h ed is p
laye d wave-
form starts at t he d esire d p oint . T h e triggering
slo pe can be
changed at any time b y rotating t h e LEVEL
/S L O PE con-
trol to t h e corres p on d i ng p oint
on
t
he oth
er
slo pe wave-
form .
Horizontal Swee p R ate
T he ΤΙΜΕ /DI V switc h provides 26 cali b rate d sweep
rates ranging from 0 .02 microsecon d / d ivision to five
secon d s/ d ivisio n . T he V A R IA BLE ΤΙΜΕ /DI V con trol must
be in the cali b rate d p ositio n and t he M AG N I F I ER at Χ 1
for t he i nd icate d swee p rate . T he V A R IA BLE ΤΙΜΕ /DI V
control incor p orates α two-position
switc h to d etermi ne if
t he swee p r ate is calibrated or un cali b rate d . Wh en t he
V A R IA BLE kno b is in t he inwar d p ositio n , t he V A R I-
A BLE TI ΜΕ /DI V con t r ol is ino p erative an d t he sweep rate
is cali b rate d . Wh en pr essed and released, t he V A R IA BLE
kno b moves outwar d to activate t he V A R IA BLE
TIME/
DI V co n t r ol for uncali br ate d sweep rates . Α calibrate d
sweep rate can be obtained at any p ositio n of t he V A R I-
A
BLE ΤΙΜΕ /DI V control by p ressing in t he V A R IA BLE
k
nob . T h is feat u re is u seful w hen α s p ecific un calibrate d
swee p rate h as been ob tai ned an d it is d esire d to switc h
between
t h is un calibrate d sweep rate an d α cali b rate dswee p
rate
. Switch i ng from u n calib r ate d to cali b rated o p eratio n o r
vice versa does not affect t he setting of t he V A R IA BLE
ΤΙΜΕ /DI V control . T he V A R IA BLE ΤΙΜΕ /DI V con trol
allows t he sweep rate i n eac h ΤΙΜΕ /DI V switc h p ositio n to
be reduce d to at least t h e sweep rate of t he next ad j acent
switc
h position . T h is p rovi d es an overall u n cali b rated vari-

F
ig .
2-7 . E ffect of
LEV E
L /S L
O PE con trol on C R T display
(A
U TO Ρ - Ρ M OD E
) .
2- 1 1