Bally 5000 Plus, Manual

Page: 320 / 388

1 2 . VACUUM FLUORESCENT D I SPLAY BOARD
Troub l eshoot i ng ( con t ' d )
Check Boa r d and G r ound
To c heck for g r ound a n d p rope r
vo l t ages a t v a r i ous I C c h i ps , see
t he
Boar d Schema t i c
I n t h i s
S e c t i on .
NOTE : Check vo l t ag e w i t h p roper l y
r e f e r enced g r ound .
R emove
If
C h i p f r om a Mu l t i - l a ye r ed
Boa r d
To r emove I C c h i ps f rom a mu l t i ­
l a y e r e d boa r d w i t hout damage t o t he
m i dd l e l aye r s ' p r i n t e d
c i r cu i t
t r aces and p a d s , fo I l ow t hese
s t e ps .
1 . I so l a t e t he f au l t y c h i p .
2 . U s i ng cut t e r s , cut t he p i ns a t
t he c h i p a n d r emove t he c h i p .
3 .
H e a t e a c h p i n w i t h a so l d e r i ng
I r on unt l I t h e so l d e r ho l d i ng
t h a t p i n me l t s .
4 . E a s i l y r emove t he p i n us i ng l ong
nose p i l e r s . T h i s l e a v e s t he
I n t e r na l t r ac e s a n d p a d s I n t a c t .
NOTE :
A cop p e r r i ng on t he p i n
s hows t he boa r d I s damage d .
5 . Ca r e f u l l y , r emove any so l d e r
f r om t he ho l e s us i ng a so l de r i ng
I r on a n d a so l de r sucke r .
R emove VFD f r om Boa r d
To r emove t he V F D f rom t he PCB ,
f o l l ow t hese s t e p s .
1 . P l ace a s t r a i gh t edge s t r i p o f
p l as t i c o r wood b e t ween t he e n d
o f t he d i sp l ay a n d t he boa r d
a s s emb l y .
2 . Wo r k i ng a l t e r na t e l y a t
gen t l y t i I t t he s t r i p
l oosen i ng t he d i sp l ay
boa r d .
1 ?_ 1 ?
e a c h e n d ,
s l i g h t l y
f rom t he
NOT E S