Yamaha DG 100-212 Service Manual page 19

(Test Contents)
The RAM Backup Battery check is executed
automatically.
When all the LEDs light simultaneously, the
Battery Check is finished. Then the DG100-212
selects the next test no., so the LED display
shows "5".
(Error Number)
E0 : Battery Low (RAM DATA are kept.)
E1 : Unknown Error
E2 : Battery Low (RAM DATA are not
kept.) or Not Installed
5. MIDI Check
Connect the MIDI IN and the MIDI OUT terminals
with a MIDI cable. Press the RECALL key when
the LED display shows "5". The MIDI Check is
started.
(Test Contents)
The loop back MIDI check is executed automatically.
When the MIDI check is started, the LED display
shows "51" and then "52". When all the LEDs
light simultaneously, the MIDI Check is finished.
Then the DG100-212 selects the next test no., so
the LED display shows "6".
(Error Number)
E0 : Error
E1 : Error
6. SRAM Check
Press the RECALL key when the LED display
shows "6". The SRAM Check is started.
(Test Contents)
The SRAM read/write check is executed
automatically.
When the SRAM Check is started, the LED display
shows "61" and then "62". When all the LEDs
light simultaneously, the SRAM Check is finished.
Then the DG100-212 selects the next test no., so
the LED display shows "7".
(Error Number)
E0 : RAM Address Error
E1 : RAM Read/Write Error
7. Flash Memory Erase/Write Check
Press the RECALL key when the LED display
shows "7". The Flash Memory Erase/Write
Check is started.
(Attention)
When the result of the test number 6 has alredy
been "Error", don't execute this test, or the
DG100-212 won't set up at normal mode by the
rewrited wrong data in the Flash Memory.
Don't turn the POWER switch off while executing
this test, the DG100-212 won't set up at normal
mode by no data in the Flash Memory.
(Test Contents)
The Flash Memory Erase/Write check is executed
automatically.
When the check is started, the LED display shows
from "70" to "73" successively. When all the LEDs
light simultaneously, the Flash Memory
Erase/Write check is finished. Then the DG100-
212 selects the next test no., so the LED display
shows "8".
(Error Number)
E0, E1 : Flash Erase Error
E2, E3 : Flesh Write Error
8. Sound Check
Before executing this sound check, the idling
adjustment, the output wave adjustment and
center voltage adjustment must be finished. the
three adjustments can be done while the LED
display shows "8".
(Idling Adjustment)
1. set the idling adjustment volume (VR303) at
minimum.
2. connect the 4ohm load to the speaker terminals.
3. Set the output volume at minimum.
4. Adjust the VR303 so that the DC voltage between
the terminals of the RA301 should be 5 mV +/-1 mV.
(Output Wave Adjustment)
1. After adjusting the Idling adjustment, set the
OUTPUT VR at maximum.
2. When the signal of -2dBm / 1 kHz is inputted from
the RETURN terminal, adjust the VR 301 (4.7
kohms) so that the wave shape should be a sine
wave symmetrical for upper and lower as below.
T•P
(Center Voltage Adjustment)
1. Adjust the VR302 so that the voltage of the
output circuit (RA301) should be 34 +/- 1 V.
* By adjusting the Output Adjustment and the
Center Voltage Adjustment alternatively, search
the best point.
After finifhing the adjustments above, press the
RECALL key when the LED display shows "8".
The Sound Check is started.
DG100-212
T•P
0.22x2 RA301
Adjust the VR301
to be a sine wave.
19