Tektronix 2235 - TRIGGER

L
CH 1
C H 2
BOTH and ADD
r
L,
BOTH and CHOP
BOTH and ALT
TRIGGER SO UR C E Switches-Two butto
n
s
t h
at se-
lect t he sou
r
ce of the internal triggering signal for t he
Α T r igge r w hen the Α SO U RC
E switc h
is set
to
INT .
C H 1-T he signal applie d to t he C H 1 OR Χ
inp
u t
conn ecto r is t he sou
r
ce of t
h
e t
r igger signal .
C H 2-T he signal applie d to
t h
e C
H 2
O
RΥ i np ut
co
nn
ecto
r
is t he sou
r
ce of t he trigger signal
.
T he
C ha nn el 2 POSITION control,
whe n p
ulled out,
will
inve rt t he C h annel 2 trigger sig n al .
COMP OSIT E -T h e sig n al a pp lied to eit
h
e
r
o
r
bot
h
vertical inp u t connectors is the sou rce of t h e trig-
ger signal . CO MPOS I TE T R IGG ER SOUR C E is
selected w h e n both CH 1 an d CH 2 bu tto ns are
eit he r out o r pr essed i n . T
h
e
trigge r
sou
r
ce is de-
ter m ine d by sig n als selecte d fo r dis p lay by the
VER TICA L M OD E switc
h
es . See Ta b le
2-2 for
CO M POSITE
TRIGG ER
SO UR
C E .
VER T M OD E Trigger So urce
C H 1 O RΧ inp u t signal .
C H 2 O RΥ inp u t signal .
Algebraic s u m of CH
1
OR Χ and
C H 2 O RΥ i np ut sig n als .
Algeb r aic sum of C H 1 OR Χa n d
C
H 2
O
RΥ in p
ut
sig n
als .
Alte
rn
ates between C
h
a
n nel 1
and
C
h annel 2
on every other swee p
(i .e . C H
1
OR Χ in p ut
sig n
al t
r
igge
r
s
t he sweep t h at d isplays Channe l 1,
and C
H 2
OR
Υ inp
u
t sig n al triggers
the swee p t
h
at dis p lays C
h
a
nn
el
2) .
BW L I M IT- Wh en pr esse d i n, t h is button switc h limits
t he b an d wi d t h of the vertical amplifier and t he Α Trig-
ger
system to approximately 20
MHz .
Bu tton m u st be
p ressed α seco
n
d time to
r
elease it a
n
d
r
egai
n full
100 ΜΗτ ba nd widt h o pe r ation . Pr ovi d es α met h o d fo r
re du cing interference f rom high-frequency sig n als
w h
e
n viewing low-frequency signals .
Pr ep aratio n fo r U se-2235
ΑΝ /
U
S M -488 O p erators
AMP
CA L Co nnecto r -Provides an approximately
0 .5
V, negative-goi n g,
square-wave
voltage (at ap-
proximately 1 kH z) t h at permits an o pe r ato r to co m -
p e
n
sate
voltage pro b es and to check operation of t he
oscillosco pe vertical system . It is not inten ded for veri-
fying
t he accu racy of t he vertical gain o r ti m e-base
ci r cuitry .
G
N D
Connector-
Provides di r ect conn ection to t he
instr u me n t chassis ground .
S ER IA L an d M od Slots-T h e S ER IA L slot is im-
printe d wit h t he i nstrumen t's se r ial nu m ber . T h e M od
slot conta i ns the option num b er t h at is instal l ed in t he
i
n
st
r
u
m
e
n t .
H O R IZO N TA L
R efer to F
ig
u re
2-5 for locatio n of ite m s 22 throug h 28 .
Α and Β SE C/DI
V
Switc
h es-Used to select t he
swee p spee
ds fo r t he Α a nd Β Swee p generators in α
1-2-5 sequence .
To
ob tain cali b rate d swee p s p eeds,
Ta b le 2-2

t he Α and Β S
E
C/DI
VV aria b le control m u st b e in t he
Com p osite T r igge r Sou r ce

cali b rated d ete n t (fully cloc
k
wise) .
ι ι
ΑS
E
C/DI
V -T h e cali b rate d sweep s p eed is
sh ow n between the two blac
k lines on t he clear
plastic s k irt . T h is switc h also se l ects t he delay time
for d elaye d -swee p o pe r atio n wh en used i n con-
junction
with the Β D ELAY TIME P OSITIO N
cont r ol
.
αΡο = I 7 I οΝ L :>
25
ο
FOA I = ο οοΕ
2s
Α
σ
TRIG V I EW Switc h - Press
and
h old t he button i n to
d isplay α sam p le of t he signal present i n t h eΑ Trigger
amplifier ( f or all Α SO UR C E switc h settings) . All ot h er

49 τ 6- αε
dis p lays are
removed
w h ile t he T R IG V IE W b u tton is
h el d in .

F ig u
re
2-5
.
H orizontal
contro
l
s an
d
i
n
dicator
.
2-7