TllOUBLE
SB001'IRG CHAR
T
SYMPTON
N o pow e r
No s o und or
p i c t u re
No p i c t u re
No func t i on
N o p i c t u re or
sound
POS S I BLE CAUSE
Power swi tch not
t u rne d on
Pow e r cable not
conne c t e d
Wrong
TV
channe l
Loo s e video cab l e
TV vo l umn and co lour
t oo l ow
No ma s t e r c l ock
+ 5V
+1 2V
- 1 2V
-SV
RESET
No ma s t e r c l ock
Inte rrupt
ROM c h ip se l e c t
Use r RAM ch ip se l ec t
Wrong TV channe l
Loo se video cab l e
VRAM ch ip se l e ct
VDP in terrup t
3.13
REMEDY
Tu rn on pow e r sw i tch wh ich i s
on right-han d s i d e o f the
mac h i ne .
Be sure t he pow e r c ab l e i s
connec t e d to the
c
ompu t e r and
r e p l ace the brown fuse .
S e l e c t c o r r ec t
TV
channe l .
Be s u re a l l video cab l e s a re
s e cu re ly fas t e ne d .
Ad j us t
TV
the vo l umn con t r o l
and co l our l e ve l o f your TV .
Use o sc i l l o s cope t o check IC23
pin 4 and IC36 P in 39 .
C8 and 7 805C p i n 2
C 1 1 4 and 7 8 1 2 C p i n 3
7 9 1 2 C p i n 3 or 79L05 p in 2
7 9L05 p i n 3 and C85
IC3 7 pin 26
IC36 pin 3 9 , 3 8 and IC3 7 p in 6
IC3 7 p in 1 7 , 1 6 , 1 9 and 2 0
IC36 p i n 1 6
IC3 1 p in 1 1 , 1 2
IC 1 -
8 and I C 1 7 ,
18 ,
p in 3,
4 , 1 5
S e l ect correct TV channe l
Be sure a l l video cab l e are
s e cure ly f a s te ned
IC9 -
1 6 , p i n 3 , 4, 1 5
IC36 , p i n 1 6
Содержание MKI
Страница 1: ...SERVICE TECHNICAL MANUAL VOL 1 l SVI318 328 MKI MKII COMPUTER SYSTEM SVI SPECTRAVIDEO ...
Страница 7: ...4 Remove the seven retaining screens 5 Remove the cover 2 2 ...
Страница 8: ...6 Remove the screens on the metal cover 7 Remove the metal cover 2 3 ...
Страница 9: ...To r e assemble u se the above procedures in the rever se order 2 4 ...
Страница 134: ...5 CIRCUIT SCHEMATIC AND COMPONENT LAYOUT 5 1 ...