Tektronix 7A16A User manual

1 Ν ST F t U C - Γ 10 Ν
ΜΑΝ
V A L
7
Α 16 Α
A MP L
I F I ER
Serial Nu mber
Te k t r o n ix,
Inc .
t Ρ .
Ο . Box500

t

B eaverton, Oregon 97005

+

Ph o ne : 644-0161 t Ca b les : Te k tronix
070-1378-00

772

W A RR AN TY
All TEK TR O N IX instr u ments are warrante d against
d efective m aterials an d wor k ma ns h i p for one year . Any
questions with res p ect to th e warranty s hould be ta k en up
with you r TEK T R O N IX F iel d Enginee r or re p r esentative .
All requests fo r r e p ai r s an d r e p lace m ent p arts s h ould be
d i r ecte d to the T EK TR O N IX F iel d Office o r r ep r ese n tative
in yo u r ar ea
.
T h is will assure you t he fastest p ossible
service
. P
lease incl u d e t he instrument Ty pe Nu mbe r or P art
N
umbe
r
and Serial Nu m be r with all re q uests fo r p arts or
service .
S p ecificatio n s an
d
p r ice
c
hange p rivileges
reserve d
.
Copy r ig h t © 1972 by Te k tronix,
Inc ., B
eaverton,
O
r
egon
.
Pr i n te d in t h e U nited States of
America . All, rig h ts reserved .
Conte n ts of t h is pu b lication
may
not
be
re pro
d uced
in
any
fo r m with out permission of Te k tr onix, Inc .
U .S .A . an d foreign T EK T R ON IX pro d ucts cove r ed by U .S .
and foreign patents
and/or
paten
ts p
e nd ing .
T EK T R O N IX is α registere d t r ademar kof Te k tro n ix, In

TA BLE O F CO N T EN
TS
S E
CTIO N 1

S PE CI F ICATIO N
S E CTIO N 2

O PER ATI NG I N ST RU CTIO NS
SECTION3

CIRCUIT DESCRIPTION
SECTION
4

M AINTENANCE
SECTION 5

CALIBRATION
SECTION
6

ELECTRICAL PARTS L IST
Abbreviations an d Symbols
P
arts Ordering Information
SECTION 7

DIAGRAMS AND CIRCUIT B OARD
ILLUSTRATIONS
Symbols and R eference Designators
SECTION 8

MECHANICAL
PARTS LIST
M echanical Parts L ist
Information
Index of M echanical Parts
Illustrations
M echanical Parts L ist
Page
Intro d u ction

1-1
Electrical C h aracteristics

1-1
En vi r
onmental C h ar acteristics

1-2
Ph
ysical
C h aracteristics

1-2
Installation

2-1
Function of Controls
and Connectors

2-1
B asic O p eration

2-2
General Operating Information

2-2
Ap p lications

2-3
B lock Diagram Description

3-1
Detaile d Circuit Description

3-1
Preventive M aintenance

41
Troubleshooting

4-1
Corrective
M aintenance

4-3
Performance
Check

ς -1
Test Eq
ui
p
ment R e q uired

ς -1
Short
Form
Proce
d
ure

ς -2
Calibration Procedure

5-3
B alance

5-4
Gain

5-4
Com p
ensation

5-5
B andwi
d th
and
Risetime

5-6

Fig .
1-1
.
7
Α 16 Α
Amplifier Plug-in
.

Introduction
T h e 7 Α 16 Α Am p lifier Plug-in U nit is α wi d e-ban d wi d t h
am
p lifier
d
esigne d for use with T EK TR O N IX 7000-Series
C
h
aracte
r ist i cs
Deflectio n F acto r
Cali brate d Range
Acc ur acy
Un cali br ate d (V AR IA BLE)
Gain R ange
F re quency R es p o n se
Ba ndwi d t h
AC Co up le d ( L owe r B andwi d t
h
L
imit)
1
10 Hz or less .
20 MHz Bandwi d t h
Ste
pR es po n se
20 MH z B a n d wi d t h R iseti m e
M aximu m
In p
ut
Voltage
DC Co
u pled
AC Co
up le d
S PE CI F ICATIO N
TA BLE 1-1
ELE CTR ICA L
Pe r fo r ma nce R equ i re m e n ts
5 m V / d iv

to

5 V / d
iv,

10 ste
p
s

i n

α

1-2-5
se qu ence .
W it h i n 2 ο
/
ο of in d icate d d eflectio n facto r wit h
GAI N a dju ste d at 10
m
V / d iv .
Co n tin u ously varia b
le betwee n calibrate d ste p s ;
exten d s d
eflectio n facto r to at least 12 .5 V/ d iv .
Wit h 7400-Se r ies

Ι

Wit h 7500-Series
60 MHz

Ι

90 MHz
W it
h 7700-Series

W
it h 7900-Se r ies
150 ΜΗτ

225 MH z
R
iseti
m e

Ι

W it h 7400-Series

W it h 7500-Series
5 .9 n s

3 .9 n s
W it h 7700-Se
r
ies

W it
h
7900-Series
2 .4 n s

1 .6 ns
Section 1-7 Α 16 Α
Oscillosco p es . T h e 7 Α 16 Α can be o perated in any p l u g-in
com p artme n t of 7000-Series Oscillosco p es . Rea d out
enco d ing an d trace i d entify f u nctions are p rovide d to
r eadout e q ui pp ed oscillosco p es .
S up p lemen tal Information
P e rm its a dju st m e n t of d eflectio n facto r for
cali br ate d o p er ation wit h
all
7000-Se r ies main-
fra m es .
20 MH z, ±3 MHz .
21 n s maxi mum .
250 V (DC
+
pea k AC) ; Α com
pon ent
500
V
Ρ - Ρ maxim
um, 1
kH
z
or
less .
500 V (DC
+ peak
AC) ;
Αcom p one n t 500 V
Ρ - Ρ
maxim um, 1 kH z or less .

S p ecification-7A16A
TA BLE 1-1
(
εοπ t)
C
h a r acte r istics

Pe r fo rm a nce
R
eq
u i r eme n
ts

Su p p lemental
Informatio n
Input
R
and
C
R
esistance

1 ΜΩ t2% .
Capacita nce

20 p F ±0 .5 pF .
Ove rd rive R ecove r y Ti m e
DC Drift
TA BLE 1-2

TA
BLE 1-3
ENV
I
R O
NMEN TA
L
CH A R ACT ER ISTICS

PH YSICA L
0 .1 m s o r less to recover to
wit h i n one d ivisio n
after re m oval
of ove rdr ive sig n al of up to
+75
d iv or -75 d
iv rega rd less of ove rd rive sig n al
du ration .
D r ift wit hTi m e (Ambient Tem p
0 .02 d iv o
r
less in any one
min u te afte r one
an d L ine V oltage Co n sta
n t)

h
our
warm up .
D
r ift
wit
h
Te
mp e r
at
ur e
(
Line

Ι

N ot m ore than 0 .02 d iv/ ° C .
V oltage Co n stant)
Size

F
its all
7000-Se r ies p l u g-i n co m pa r tments .
R efer to t h e sp ecificatio n s fo rt he associate d
oscillosco pe .

W eig ht

0 .9
kg or 1 .9 l bs .

O PER ATI N G I N
ST RU CTIO N S
General

POSITION
Installation
inscribe d wit h t he unit i d
entification "7 Α 16 Α ") and t h e
plug-in
will un latc h . Continue p ulli ng on
t he latc h to sli de

GAIN Ad j ustme n t
t h e
7 Α 16 Α o u t of t he oscilloscope .
F unctions of
Controls an d Co n nectors
F ront Panel
I NPU T Co n nector
P
rovi d es signal connection
to t he am p lifier .
AC-G N D-DC Switch
Selects sig n al i npu t
coup ling mo de .
AC : T he AC com po n e n t of t h e signal
is cou p led to t he
in p ut w h ile t h e DC com ponent is b loc ke d .
DC :
B
ot h AC and DC com p onents of t he sig n
al is
coup
le
d to t he amplifier i np ut .
P O L A R ITY Switc h
P rovi d es α mea n s of i n verting t h e
d
is p
lay .
B
A N
D W IDT H Switc h
Sectio n 2-7
Α 16 Α
To

effectively

use

t he

7 Α 16 Α ,

t he

operation

an d
Controls p osition of t he trace .
capabilities of t
h
e instrume n t must be k nown . T h is section
d escribes
front-panel co
n
trol
f u
nctions, general information
on sig n al in p ut
co
nn ections,
an d ot h er sub j ects t h at p ertain

ID EN TI F Y P
us
hbu
tton
to various measurement
app
licatio
n s .

Deflects trace about
0 .3 d
ivisio
n for trace i d entification .
In i n str u ments with rea
d out,
also re
p laces rea d o u t wit h t h e
wor d "ID EN TI F Y" .
T h e 7 Α 16 Α is cali br ate d and rea
dy for use as receive d . It

VO L TS/D I V Switch
can be
installed in
any com partment of T EK TR O N IX
7000-Series Oscillosco
p es, but is inten d e d for u se p rimarily

Selects cali b rate d d eflection factors from
5 mV / d iv to
in vertical p lug-i n com partmen
ts . To install, alig n t h e u pp er

5 V / d iv ; 10 ste p s in α 1-2-5 se qu ence .
and lower rails of the 7 Α
16
Α
with t he oscillosco p e trac k s
and i n sert t he p l u g-in . T h e front
panel will b e fl u s h wit h t he
fro n t of t h e oscillosco pe w h e n t he p lug-in
is inserted, an d

V A R IA BLE
(
VO L TS/DI V )
t he latc h at t he b ottom-left corner will
be in place against
t he front
p anel .

P
rovi d es continuously variable uncali b rated
settings be-
t w
een
calibrate d ste p s . E xte nd s t h e deflection
factor to
To remove t he 7 Α
16
Α ,
pull on t he latc h(wh
ic h is
12 .5 volts/ d ivisio n or m ore .
Screw
d
river
ad ju stment permits calibratio n of d eflection
factor
.
+ UP : Α positive-goi ng signal at
t h e I NPU T con n ecto r
d eflects t h e C R T d isplay up
ward .
I NVER T : Α positive-goi ng sig n al
at t he
I
NPU T con-
nector d eflects t he C RT d is p
lay
d ownwar
d .
Pr ovides α m ea n s of limiti n g t he upper ban d wi d t h .
FULL : Allows t h e 7 Α 16 Α to op erate at f u ll rate d
GND : Gro u nds t he am p lifier in p
ut w h ile main taining t he

b an d widt h .
same loa d at t h e I NPU T connector . P rovi
d es α p at h for
p re-c h arging t h e AC cou p ling ca p acito r
(t
h
is feature p ro
tects
b ot h

t he 7 Α 16 Α an d t h e so u rce
generator from

20 MH z : R e d uces t he u pp er b andwi d t h of t h e 7 Α 16 Α
to
p ossi b le
over-voltage conditions)
.

about 20 MH z .

O peration-7 Α 16 Α
B ASIC O PER ATIO N

T he T EK TR O N IX Ρ 6053 p ro b e is eq ui pp e d with α
rea d out cod ing ring w h ic h connects to α circ u it
in
t
he
Ge n eral . T h is proce d ure d emonstrates t h e use of t he

am p lifie r unit . T h is automatically corrects t
h e rea
dout
co nn ectors a nd controls of t h e 7 Α 16 Α , w h ile at t h e same

d is p layed on t h e C
R T
to t h e actual d
eflection factor
at
t he
time provi
d
ing
α
mea n
s of
check
ing th e basic operation of

ti
p
of t he p ro b e .
T h
is p ro b
e is recommen de d for use wit h
t he instrument .

t he7 Α 16 Α and an oscilloscope
e q u i p pe
d
wit h readout . T he
T EK
T
R O N IX
Ρ
6054 p ro b e is
electrically ide n tical to t he
Ρ
6053 b ut is
inten
d
e
d for use wit
h systems not eq u i pped
Pr eliminary Set up . I n
stall t
he 7 Α
16
Α
into any 7000-

wit h rea d out . For more information refer to t he Te k tronix,
series
oscilloscope vertical compartment an d set t
he
oscillo-

Inc . catalog .
sco p
e VER TICA L M
OD
E
an d
T R IGG ER SO
UR C
E
to t he
p
ro
p er setti
n gs
.
Install α 7-series time-base unit into α h o r izontal

Vertical Gain C h ec k and A d j ustment
com partment an d set t he oscillosco p e HO R IZO N TA L
To ch ec k t he gai n of t he 7 Α 16 Α , set t he VO L TS/DI V
M OD E to t h e p ro p er setting . Set t he time- b ase unit to α

s w
itc h to 10 mV a nd connect α40 m V, 1 kH
z
sig n al from
swee p rate of on e-milliseco ndper division an d set t he

the
oscillosco
p
e calibrator
to t
h e In p
ut
connector . T h e
triggeri ng mode to
A
U TO .

vertical
d
eflection
sh ould be
exactly four
d
ivisions
.
If
not,
a d ju st t he front panel
GAI N for
exactly four divisions .
Proced u re
1 . Set t h e 7 Α 16 Α AC-G N D-DC switc h to GND and
p ositio n t h e trace to t h e ce n ter of t he graticule .
2 . Set t he VO L TS/DI V switc h
to 10
m
V an d apply α
40 m V 1 kH z s q uare-wave signal from t h e oscilloscope
CA L I BR ATO R to t he 7 Α 16 Α I NPU T connector . Set t he
AC-G
N D-DC
switc h to DC and ch ec k for α fou r - d ivisio n
dis p lay .
3 . Set P O L A R ITY switc h to I NVER T
an d
ch ec
k t h at
t h e dis p laye d signal is inverted as compared
to its ap p ear-
ance in step 2 .
4 . Set t he AC-G N D-DC switc h to AC a nd ch ec k t h at
t h e trace is centere d on t h e C R T g r aticule .
5 . Set t h e oscillosco pe CA L I BR ATO R to 4 m V and t h e
7 Α 16 Α MAG switc h set to ιΧ 10 . C h ec k for α fo u r- d ivision
d is p lay .
6 . P ress t h e 7 Α 16 Α ID EN TI F Y bu tton, c h ec k t h at t h e
d is p lay moves u p ward a pp roximately 0 .3 division an d t h e
rea dou t (if so e qu ip p e d ) rea d s "ID EN TI F Y" .
G EN E R A L O PER ATI NG I NF O RM ATIO N
Signal Connectio n s
In p ut Co u pling
T
he AC-G N D-DC switc h allows α ch oice of in p ut
cou p ling met h od s .
T
h e ty p e of d is p lay d esired a nd t he
app
lie
d
signal will determine
t
h e cou p li ng
to use .
T he DC cou pling p osition ca n be use d for most
ap p lications . For AC signals wit h f r e q uencies b elow a b out
30 H
z
(10 H z wit hα10 Χ p robe), an d s q uare waves w h ose
low-frequency com p onents are imp ortant to t he display, it
is necessary to use DC cou pling to obtain α satisfactory
p resentation .
In t he AC coup li n g p ositio n t he DC component
of
t h e
signal is b loc ked b yα ca p acitor in t he in pu t circ u it . T he AC
coup ling position p rovides t he best display of signals wit h α
DC
com p onent muc h larger t h an t he AC com p on ent . T h e
p re-c h
arge feature s h oul d be use d w hen t h ere is α p ossi b ility
of h aving
α
resi
d
ual c h arge
on t
h e
i np ut ca p acitor of t h e
op p
osite polarity
to t
he
inte nded i
np
ut, and w h en t h e
algebraic sum of t h e com b i n atio n of ch arges
may b
e
greater
t han t h e maximum in p ut limitations
of
t he
am
p lifier .
To
use t h is feature, first set t he coupling switc h
to
GN D,
th
en
connect t he pro b e to t h e circ u it an d wait about two
seco
nd s for t he coup ling ca p acitor to c h arge, set t h e
coup ling
switc h to AC .
In general, p robes offer t he most co n venie n t mea n s of

T h e G N D p osition p rovi d es α ground reference at t he
con necting α sig n al to t he i n p ut of t he 7 Α 16 Α . Α 10 Χ

inpu t of t h e am p lifier without externally grou nding t he
atten u ator pro b e offers α h ig h im p e d ance and allows t h e

In p u t connectors . However, t h e signals connecte d to t he
circ u it under test to p erform very close to normal o p erating

in pu
ts are not gro
und
ed, and the
same DC
loa d is p resente d
con
d itions .

to t he signal source .

V O L TS/DI V
and V A R IA BL E

2 . Set t he
Co
u pling
switchto AC .
T h e amount of d eflectio n produced
by α sig n al is
d etermine
d by t he signal amplitu d e, t he attenuatio
nfacto r
of t heprob e, t h e setting of t he
VO
L
TS/DI V switch , and
t he setting of t h e VA R IA BLE
Control
.
Calibrate d
d eflection factors re p resente d b y t h e
setting of t he V O L TS/
DI
V switch apply only w hen t h e V A R IA BLE
con trol is i n
t he CA L p ositio n ( p ush e d -in) .
T
he VA R IA BLE control p rovides
variable
u
ncalibrate d
settings between t h
e
cali brated ste p
s of t he VO L TS/DI V
switch . W it h t h e V A R IA BLE control
outset
fully
cou nter-
clockwise
the uncalibrated d eflectio nfactor is
exten d ed to
at least 2 .5 times t he atte n uator setting .
By a pp
lyi
ng α
calibrate d voltage source to t h e I NPU T conn ector, any
specific
d eflection factor can be set with in t he range of
t
h e
V A R IA BLE
con trol
.
P olarity Switch
The P O
L
A RITY
switch p rovi d es α means of inverting
t h e
d is p laye d signal . W it h t h e P OL A R ITY set to + UP, α
p ositive-going sig n
al at t h e
I
NPU T p ro d uces an up
ward
d eflectio nof t he CRT
display .
W
it h t h e P O L A R ITY set to
I NVER T, α p ositive-going signal
will p ro d uce α d ownwar d
d eflectio nof t h e CR T d isplay .
Trace I d entification
Wh en t he ID EN TI F Y b utton is p
resse d , t he trace is
deflecte d u p war d about 0 .3 d ivision
to
i
dentify t
h
e 7
Α
16 Α
trace . T h is feature is p articularly usef u l w
h
en
multi p le
traces are d isplayed on the CR T . In
mainframes wit h
rea d out, it also re p laces t h e d eflection factor rea d out wit h
t he wor
d
"ID EN TI F
Y" .
General
A PPL ICATIONS
P ea k
-to-
P
ea
k
V oltage M easurements (AC)
Toma
k
e
pea k -to- peak voltage meas u rements, use
t
he
following p
r oce d ure :
1 . Apply t
h e
signal to t he In p ut connector .
ΝΟΤΕ
ΝΟΤΕ
P osition to
ce n ter vertical
line
Operation-7A 16A
For
low-frequency signals below about 30 h ertz, use
the DC position to prevent
attenuation of the signal .
3 . Set t h e VO L TS/DI V switchto d is p lay
about
five
vertical d ivisions of t h e waveform .
4 . Set t he time-base Triggering
controls for α stable
d is p lay . Set t he Time B ase to α swee p
rate w
h
ic h dis p lays
several cycles of t h e waveform .
5 . Tur n t he 7 Α 16 Α P OSITIO N control so the lower
p ortio n
of t
h
e waveform coinci d es wit h o ne of t he gratic u le
li n es
below t he center h orizontal li n e, and t he topof t h e
waveform is wit h in t he viewi ng area . W it h t h e time
base
P
osition co n t r ol, move t h e dis p lay so one of t he u pp er
p
ea
ks lies
n ear the center vertical line (see F ig . 2-1) .
6 . M easure t he d ivisions of vertical d eflection p eakto
p
ea
k . C heck
t h at t h e V A RIA BLE control is i n t h e CA L
p
osition .
This
technique can also be used to make measu r e-
ments between
two
p
oints on the waveform, r athe r
t han p ea k to peak .
T he following i n
formation d escribes the p r oce d ures a nd
tech ni q ues for
ma
k ing
meas
u
rements with α 7 Α 16 Α an d t h e
associate d
T EK T R
O N IX oscillosco p e and time-base . T h ese
a pp licatio n s are n ot d escri bed in d etail, since eac h a pp lica-
tio n
must b
ead
a pted to the re q ui r ements of the i nd ivi d ual
m eas u rements
.
T h
is instrument can also b e used for many
app lications
w
h ic h
are n ot described in t h is manual .

defle
V e r c
ti
ι co ι
n
Co n
tact your local T EK T R O N IX F iel d Office or represen
t-
ative
for assistance in ma k ing s p ecific measureme n
ts wit h
t h is
instrument .
F ig . 2-1 . M eas ur i ng t h e p ea k -to-pea k voltage of α waveform .
2-3

Ope r ation-7 Α 16 Α
7 . Mu lti p ly t h e d istance measu re d in ste p7b y t he

5 . Set t h e time- b ase Triggeri n g controls fo r α sta b le
V OL TS/DI V switc h setting . I n clude t he attenuation factor

d is p
lay .
Set t he Time Base swee p rate for an o p ti m um
of t he p robe if used .

d is p lay of t he waveform .
EXA MPLE : Assu me t h at t h e peak
to p
ea k vertical

6 . Measure t h e d ista n ce in d ivisio n s between t h e refer-
d eflectio
n
is
4
.5 d ivisions
using
α 10
Χ
attenuator p robe,

ence line and t he p oint on t he waveform at w h ic h t he DC
and t
he VO L TS/DI V switc h is set to 1 V .

level

is to

be measured .

For exam p le, in

Fig . 2-2 t he
measurement is between t
h e reference line
an d p oint
Α .
vertical
VO L TS/DI V
p
ro b e
Volts = d eflection Χ

Χ atten u ator
( d ivisio n s)
setti n g
facto r
S ub stituti n g t he given val u es :
Volts P
ea
k to P ea k = 4 .5 Χ 1 Χ 10
T he p ea k -to- p ea k voltage is 45 volts .
If you are usi ng α 7 Α 16 Α wit h α cod e d pro b e an d an
oscillosco p e equ i pp e d with
rea
do
u
t, si
mp ly m u lti p ly the
d
istance measured in ste p 7 b y
t
he deflection factor
d is p laye don t he CRT
.
Instantantous V oltage Measurements (DC)
To measure t he DC level at α give n point on α waveform,
p rocee d as follows :
1 . Co n nect t he signal to t h e In p ut connector .
2 . Set t he VO L TS/DI V switc h to d isplay about five
d ivisio n s .
3 . Set t h e Co up ling switc h to G ND an d p osition t he
trace to t he bottom graticule line or ot h e r r efe r ence line . If
t he voltage is negative wit h res p ect to grou nd , p osition t he
trace to t he to p gratic
u le li ne .
Do
n
ot move t he
POSITIO N
control after t h is
reference
line h as b
een
establis h e d .
NO ΤΕ
7 . E sta b lis h t he p olarity of t he waveform . W it h t h e
+ UP /I NV switc h i n t h e
+
UP p ositio n , a ny p oi n t above t h e
reference line is p ositive .
8 . Multiply t h e d ista n ce measured i n step 7 by t h e
VO L TS/DI V switc h setti n g . I n clude t h e atte n uation facto r
of t h e p robe, if use d .
EXA MPLE : Assu me t h e vertical d ista n ce measure d is
3 .6 d ivisions (see Fig . 2-2) and t h e waveform is above t he
r eference line usi ng α 10 Χ p r obe with α VO L TS/DI V switc h
setting of 0 .5 V .
U sing t h e form u la :
Instan- vertical

VO L TS/ p ro b e
taneous = d istance

Χ polarity Χ

DI V

Χ atte n uatio n
V oltage ( d ivisions)

setting facto r
S ub stit u ti n g t he given values :
Instantaneo u s Voltage
=3
.6 Χ 1 Χ 0 .5 VΧ 10
T he instantaneo u s voltage is 18 volts .
To measure α voltage level with r espect to anot h e r
Ve
r
tical
voltage rat her t h an groun d, ma k e t h e following

distance
c h anges to Step
4 .
Set t h e Coupling switc h to DC and
apply t h e refe r ence voltage to t h e Input con n ecto r .
T h en position t h e trace to t h e r efe r ence line and
disconnect t h e r efere n ce voltage .
R efe r e n
ce line
4 . Set t h e Cou p ling switc h to DC . T he gro und refe r ence

'

'
line can b e ch ec ke d at any time by switc h ing to t he GND

F i g , 2 .2,
Meas
u ri ng i n sta n ta n eo u s voltage wit h respect to same
position .

reference .