Tektronix 454A - Page 127

h . R emove t he 18- i nc h 50zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA © BN C cabl e
f r om t h e i nst r u -
ment .

f .
C HE CK - C R T d i s p l ay
f or 0 . 2 di vi si on d ef l ect i on
or
l ess
( am p l i f i er cr osst al k r at i o 100
: 1 or bet t er ) .
16 . C h ec k
Common- M o d e R e j ect i on R at i o
± . Set t he CH 1 an d C H 2 V
O
L
TS/ DI V swi t c h es t o 10
mV a n d
t he ver t i cal M OD E swi t c h t o C H 1 .
b . Connect t he o u t put of t h
e me d i um- f r e qu ency
co n st ant - am p l i t u d
e si gnal ge n er at or t o t he CH 1 an d
CH 2
i n p ut connect or s t h r oug h t he 5 nanosecond
cabl e, ± GR 50

i . C
HE CK - C RT d i s p
l ay f or 0 . 2 d i vi si on
d ef l ect i on or
© i n- l i ne t er mi nat i on
and ± d u al - i nput co u p l er .

l ess ( am p l i f i er
cr osst al k r at i o 100 : 1 or b
et t er ) .
j . W i t h out c h angi ng t he si gnal ge n
er at or ou t p ut ampl i -

c . A d j u st t h e me d i u m- f r e qu
ency si gnal gener at or f or 8
t u d e,

ch
ange

t h e

ou t p u t

f r eq u ency

unt i l

t he ver t i cal

d i vi si ons of
def l ect i o n at 50 kH z
r ef er ence .
d ef l ect i on
i s r ed u ce d t o 2 . 8 d i vi si ons .
d . Set t he ver t i cal M
OD E swi t c h t o ADD an d
pul l
t
h e
k . C HE
CK - Out p u t f r eq uency of gener at or
must be 140

I NVER T swi t c h out .
mega h er t z or h i g h er .
e . A d j u st t h
e C h a n nel 2 GAI N ad j ust ment
( on t h e f r ont
™ . Di sconnect al l t est e q ui p me n t .

panel ) f or mi ni m
u m d ef l ect i on ( op t i m u m
common- mode
r e j ect i o n ) .
15 . C h ec k C h annel 1 an
d
2
Casca d e d U pp er B an d -
wi d t h L i mi t
± . Connect
t he CH 1 O U T connect or
t o t he CH 2 i n pu t
connect or wi t h an
18- i nc h 50 © BN C cabl e .
b . Set t h
e ver t i cal M OD E swi t c h t o
C
H
2 an d t h e C H 1
an d CH 2 V O L
TS/ D I
V
swi t c h es set t o 2
m
V .
c
.
M ak e s u r e t h e ™• ¤ T R I G swi t c
h i s set t o N O RM .
d . Connect t h
e ou t p ut of t h e me d
i um- f r e q uency
const ant - ampl i t u d e si gnal
gener at or t o t he CH 1 i nput
connect or t h r oug h ± 5 nanosecon d ca b
l e, ± G R 10 § at t en-
u
at or an d ± G R 50 © i n- l i ne t er mi nat i on .
e . A d j ust t he me d i u m- f r e q u ency
gener at or f or 4 d i vi -
si ons
of d ef l ect i on at 50 kH z r ef er ence .
f . W i t h out ch angi ng t h
e si gnal gener at or out p u t am p l i -
t u
d
e, c h ange t he out pu t f r e q u ency
unt i l t h e ver t i cal
d
ef l ect i on i s r ed u ce d t o 2 . 8 di vi si ons .
g . C HE C K - Out pu t f r e q uency of
gener at or must be 33
mega h
er t z or h i g h er .
f . W
i t h ou t c h angi ng t h
e me d i u m- f r e qu ency
gener at or
out p u t
am p l i t u d e, ch ange t h
e ou t p u t f r eq u ency
t o 20
mega h er t z .
g . C HE CK - C R T d
i s p l ay f or 0 . 4 d i vi si on
of d ef l ect i on or
l ess ( common- mo d e r e
j ect i on of 20 : 1 or b et t er ) .
h . R ea d j u
st C h annel 2 GAI N ad j
ust i f necessar y i n t
he
manner gi ven i n P
er f or mance C h ec k st e
p 6 .
17 . C
h ec k Am p l i f i er
Cr osst al k
± . R emove t h
e d ual - i n p u t cou
p l er an d
appl y t he
me d
i um- f r e qu ency si gnal
ge n er at or o u t p
ut t o t he CH 2
i n p ut
connect or t h r o u g h ± 5
nanosecon d ca b l e an d
± GR 50
© i n- l i ne
t er mi nat i on .
b . Set t h
e ver t i cal M OD E swi t c
h t o CH 2 an d t he C H
2
V
O L TS/ DI V swi t c h
t o . 2 .
c . Pu s h t he I
NVER T swi t c h i n .
P er f or mance
C h ec k - 454 ‘ / R 454A
d . A d j ust t h
e me d i um- f r e q uency si gnal
gener at or f or 2
d i vi si ons of d ef l ect i on
of 50 MHz si gnal .
e . C h ange t he CH 1
an d CH 2 V O L TS/ DI V
swi t c h es t o
20 m
V
a n d t h e ver t i cal M
OD E swi t c h t o CH 1 .
g . Di sconnect t h e
50
©
i n- l i ne t er mi nat i on
f r om t h e C H
2 i npu t
connect or an d a n d
r econnect i t t o t h
e
CH
1 i n p ut
co n nect or .
h . C h ange
t h e ver t i cal M
OD E swi t c h t o C H 2 .
5- 1 3