Marantz SA-12S1, Service Manual

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Check for laserlight.
Switch the focus off
Hf path
Play DVD test disc.
Measure outputs of diodes A, B, C, D, E, F.
Measure DVDALAS outputs
5.6 Test instructions Display board
5.6.1 Display board
Introduction
These test instructions are written for all versions of the
display PCB.
The contents of the PCB can be split up into next blocks:
Figure 5-10
Functionality description:
The essential component of the display PCB is the uP
(slave). This slave works on an 8MHz resonator and has a
reset circuit that is triggered by the +5Vstby. After the reset
pulse, the standby control line will release the reset of the
host uP. This host uP will then initialise the slave. In addition,
when going to stand-by, the slave will put the host uP in reset.
When the slave receives the right IR or key code to leave the
standby mode, the reset of the host uP will be released.
Other slave functions are:
Square signal generator to generate the filament voltage,
which is required for an AC FTD.
Generates the grid and segment scanning for the FTD.
Generates a scanning grid for the keys (separated from
display scanning).
Has inputs for RC (RC5 and RC6).
General
Oscilloscope measurements have been carried out using
a Philips PM3392A.
Impedance of measuring-equipment should be > 1M
Ω
.
To do correct measurements we recommend to use
supply 3122 427 21370, which is used in all "second
generation B" DVD-players. Make sure that the main
3.3V has a 0.7A load.
Name Testpoint Value
A F140 2.6V±0.2V
B F141 2.6V±0.2V
C F143 2.6V±0.2V
D F144 2.6V±0.2V
E F147 2.6V±0.2V
F F148 2.6V±0.2V
Name Testpoint Value
RFO DC F146 2.5V ± 0.2V, eyepattern 1Vptp
O1 F155 25mV±10mV
O2 F158 25mV±10mV
O3 F168 25mV±10mV
O4 F165 25mV±10mV
S1 F174 25mV±10mV
S2 F175 25mV±10Mv
PM3394B
ch1
CH1 2.00 V~ MTB 500ns ch1+
1
FO CL 06532152_048.eps
051200
µProcessor
I2C
Display
Key-matrix
RC-Eye
V filament
V filament
Buffer
Supply:
+5Vstby
+12V
-40V
RC-6
I/O