Tektronix 454A - Page 156

A dj u st ment - 454zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
‘ / R 454A
10 . R ei nst al l
Q44 i n i t s soc k et .
11 . R e m ove t h e s p
eci al BN C cabl e f r om t h e si g n
al
so u r ce an d r e p l ace i t wi t h
± G R 5092 i n- l i n e t er mi n
a-
t i on .
12 . R
ea
dj
ust V er t i cal Cent er i n g a d j
ust ment R 334 as
gi ve n i n A dj ust me n
t
P
r oce d ur e St e p 14 .

di s p l ay .
14
.
A dj u st R 16 a nd C16 f or mi n i mum
a
b
er r at i o n s .
15 . Ad j ust R 49 H an d
C49 H f or b est p ul se- t o p
f l at ness .
5- 42
16 . A d j ust R 44 and C45 f or b est p ul se f r ont
cor ner .
19 .
AD JU ST- C25 E f or
best f r ont cor ner .
20 . Set t h e C H 1 V
O L TS/ DI V swi t c h t o
50 m V and
r ead j u
st t h e f ast - r i se pu l se
gener at o r f or ± 4- di vi si on
d i s p l ay .
21 . AD JU ST- C16, C22
an d R 33 f or b est f r ont
cor n
e r an d pu l se- t o p f l at ness .
• Ÿ¤•
R 16,
C16, R 33 a nd C22 h ave t h e
most ef f ect i n t h e
50m V p osi t i on
of t h e VOL TSI D/ V swi t c h .
22 . I f necessar y, t h e val ue
of R 29 ca n b e sel ect e d t o
ac h
i eve mi n i mum aber r at i o n s .
23 .
Set t h e C H 1 VO L TS/ DI V swi t c h
t o 5 m V and
r ea dj ust t h e f ast - r i se p
ul se ge n er at or f or ±
4- di vi si o n
di s p l ay . Add at t e n uat i on
as necessar y t o obt ai n t h
e
d esi r ed d i s p l ay ampl i t u d e .
24 .
AD JU ST- R 49G an d C49G f or best f r ont
cor ner .
F i g .
5- 11 . L ocat i o n of C H 1 compe
n sat i o n a d j ust me n t s .

25 . Set t h e C H 1 V
O
L
TS/ DI V swi t c h t o 2 mV
and
r ea dj ust t h e f ast - r i se pu l se ge
n er at or f or ± 4- di vi si on
7 . C h
ec k t h e C R T d i spl ay f or
o p t i mum r i set i me
and

d i s p
l ay .
f l at t o p . A b
er r at i ons s h oul d b e
3% ¿ or l ess . Use t h e
n ar r ow pul se
am
p
l i t ud e as an i n d
i cat or of am p l i f i er

26 . AD
JU ST- R49A f or b est cor ner .
b
andwi dt h . T h e n ar r ow
pul se am p l i t u d e s h o u l d
be 52% ¿
or m
or e of t h e l onger pul se am p
l i t u d e .

27 .

R e p eat

st e p s

14

t h
r oug
h
 26

unt i l

p r o p er
comp ensat i o n i s obt ai n ed i n al l
posi t i o n s of t h e VO L TS/
8 .

I f t h e C R T d i spl ay exceeds
t h e l i mi t s of t h e c h
ec k  D I V
swi t c h .
st e p , ad j ust C78, R 75, C90
an d R 90 as
necessar y t o
o b
t ai n t h e best r i set i m e a n d f l at
t o p .
22 . Ad j ust C h annel
2 P r eam · H i g h - F r e q uency
9 . Di sco n nect
t
h
e s p eci al BN C cabl e f r om
t h e i n st r u-

Compensat i on
ment .
± . R
emove t h e G R 50 © i n - l i ne t er mi nat i on
f r om t h e C H
1 i n p ut connect or an d
r e- i nst al l i t on t h e C H 2 i n p u t
con-
nect or .
b . Set t h e ver t i cal M
OD E swi t c h t o C H 2 .
µ .
Set t h e f ast - r i se pu l se ge n er at or
f or ± f o u r d i vi si o n
13 . Appl y t h e si gnal f r om
t h e f ast - r i se pu l se ge n
er a-

d . Cent er
t h e d i s p l ay ver t i cal l y wi t h
t h e P OSI TI O N
f o r t o t h e C H 1 i n put
co
n
nect or an d a d j ust f or
±

cont r ol .
4- di vi si o n di s p l ay at 10 m V /
d i v .
e . C HE C K - C R
T d i s p l ay f or o p t i m u m r i set i me a
nd f l at
t o p . U se t h e nar r ow
pu l se r es p onse am p l i t u d e as an i n d i -
cat or of ver t i cal am p l i f i er
ban d wi d t h . T h e nar r ow pu l se
am p l i t u d e s h oul d be 40% ¿ or
mor e of t h e l onger p ul se am p l i -
t ude i n or der t o meet r i set i me s p
eci f i cat i ons i n al l p osi t i ons
of
t h e
V
O L TS/ DI V swi t c h except 2 m V an d 5
m V .
17 . R 417 may b e
r ead j ust e d i f necessar y f or best

Mi n i mum r i set i mes s h oul d be :
pul se- t o p f l at ness . R ec h ec k
ver t i cal gai n i f R 417 i s
a dj ust e d .

10 m V , 20 m V a n d
50 m V  2 . 4 nanoseco nd s
5 mV

3 . 5 nanoseconds
18 . Set t h e C H 1 V O L TS/ DI V
swi t c h t o 20 m V a n d

2 m V  7 nanoseco
nd s
r ea d j u st t h e f ast - r i se pu l se ge n
er at or f or ± 4- di vi si on
d i s p l ay .

Aber r at i o n s s h o u l d not exceed 4% ¿ pea k t o p ea k t ot al .