Advertisement
4-8
•
In position SEARCH the ATSB signal is "low" (test
point 89; pin 22) (Attenuation Audio Signal)
•
Check the MUSB signal test point 90; pin 23
((Soft
Mute)
This signal is "low" in positions:
PAUSE
NEXT or PREVIOUS when jumping from one track to
another.
Fast SEARCH when the search button is kept
depressed for some time.
VII. DAC IC (Dual Digital Analog Converter)
e
Check the signals between Filter-B IC and DAC IC
-
See sub.
"VI.
Filter-B IC":
• Check the timing signals between Filter-8 IC and
DACIC
e
Check the output of the OP-AMP after the DAC IC
-
Place a disc on the turntable.
-
In position PLAY or in SERVICE POSITION 3, the
analog (music) slgnal should be present at the output
of the OP-AMP, after the lead-in track has been read.
VIII. DEEM CIRCUIT
e
Check DEEM circuit
-
Place test disc 5 on the turntable.
-
During playback of track no. 14 (recorded without
PRE-EMPHASIS) the DEEM signal
at
test point 84
should be "low·.
-
During playback of track no. 15 (recorded with
PRE-EMPHASIS) the DEEM signal
at
test point 84
should be "high".
-
During playback of track no.
14
the analogue signal
should be present at the source of
6583
(test point 91)
and 6582 (test point 92).
-
During playback of track no.
15
the analog signal at
the source of
6583
(test point
91)
and
6582
(test point
92)
should be
O
V.
IX. KILL CIRCUIT
-
During switching on and off the mains voltage the
signal on the collector of
6580
(to be measured on a
jumper, tp93) should
be as
indicated in the figure below.
-2V
-av
ois•c~
1 ,
'
POWER ON
2V
ov
X.
FAVOURITE TRACK SELECT (FTS)
Attention:
-av
When repairing a CD player it is important that the
contents of the FTS memory (EEPAOM) should not
unnecessarily be filled.
If not complaints are reported about the functioning of
the FTS, a check of the functions of the EEPROM should
be left undone.
The EEPROM IC is in the Stand-by mode when CE and
WE are both high.
~
~
~
-{CJ-
~
-c=:J-
-c:::J--
*
~I-
~I-
~I-
QJ;Ln--
~I-
-41--
~I-
*
~I-
0
2W
i:S;
220ko
5%
(CR 16)
>
270ko
10%
033W
!St
1Mo
5%
(CR 25)
>
1Mo
10%
033W
5%
(SFR25)
025W
~
10Mn
5%
(VR 25)
>
10Mo
10%
O.SW
=Iii
1Mo
5%
(CR 37)
>
1Mo
10%
0.67W
5%
(CR 52)
115W
5%
(CR 68)
Ceramic pla1e
Polyester flat foil
Polyester mepolesco
Mylar
{Polyes1er flat loil small sized)
M1cropoco
Tubular ceramic
(body colour pink
or
yellow/green)
Miniature single elco
S ubm,nialure tantalum
*
a•2.5V
b=4V
c-6,3V
d=10V
e-16V
f-25V
g-40V
h-63V
,-1oov
1-125V
1~12sv
m-150V
n•160V
q=200V
r=250V
s=300V
I=350V
u~400V
v=500V
w-630V
x=1000V
A•l 6V
B=6V
C=12V
D•15V
E-20V
F-35V
G=50V
H~75V
1-aov
MDA00084
T32-735
cs
9 990
.
(
C
(
Advertisement
