– 18 –
TEST MODE
This set have the test mode function. In the test mode, FM Auto
Scan/Stop Level and AM (MW) Auto Scan/Stop Level adjustments
can be performed easier than it in ordinary procedure.
<Set the Test Mode>
1. Turn ON the regulated power supply. ( The clock is displayed)
Note:
Press the
[OFF]
button, if the clock is not displayed.
2. Push the preset
[4]
button.
3. Push the preset
[5]
button.
4. Press the preset
[1]
button for more than two seconds.
5. Then the display indicates all lights, the test mode is set.
<Release the Test mode>
1. Push the
[OFF]
button.
MD SECTION
MD section adjustments are done automatically in this set.
3. Adjust the volume RV2 on TU1 by turning clockwise untill
“0” is shown next to “FM” on the display window, If “0” is
already shown or the volume RV2 has been turned too far,
turn it back counterclockwise untill “0” is disappeared once,
then try this adjustment.
Display
SECTION 3
ELECTRICAL ADJUSTMENTS
See the adjustment location from on page 22 for the ad-
justment.
TUNER SECTION
0 dB=1 µV
Cautions during repair
When the tuner unit is defective, replace it by a new one be-
cause its internal block is difficult to repair.
Note:
Adjust the tuner section in the sequence shown below.
1. FM Auto Scan/Stop Level Adjustment
2. FM Stereo Separation Adjustment (MDX-C7970)
3. FM Stereo Separation Adjustment (Wide) (MDX-C7970R)
4. FM Stereo Separation Adjustment (Narrow) (MDX-C7970R)
5. FM RDS S-Meter Adjustment (MDX-C7970R)
6. AM (MW) Auto Scan/Stop Level Adjustment
FM Auto Scan/Stop Level Adjustment
Setting:
[SOURCE]
button
: FM
FREQUENCY SELECT switch : FM 200 k (E model)
Procedure:
1. Set to the test mode.
2. Push the
[SOURCE]
button and set to FM.
Display
set
antenna jack (CN1)
FM RF signal
generator
Carrier frequency : 97.9 MHz (MDX-C7970)
98.0 MHz (MDX-C7970R)
Output level
: 22 dB (12.6
µ
V)
Mode
: mono
Modulation
: 1 kHz, 22.5 kHz deviation (30%)
0.01
µ
F
SHUF
*1
SHUF
*1
*1: MDX-C7970R indicates “98.00”.
Adjustment Location: See page 22.
Summary of Contents for MDX-C7970/C7970R
Page 4: ... 4 SECTION 1 GENERAL This section is extracted from instruction manual ...
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Page 41: ... 61 4 20 SCHEMATIC DIAGRAM SUB Board MDX C7970 C7970R Page 54 Page 57 ...
Page 48: ... 68 6 IC700 X1 KEY Board 1 IC801 º OSC IN 5 8 Vp p 271 ns 2 8 Vp p 3 5 µs ...