Sharp RT-W800H - Circuit Adjustment; Audio Section Adjustment

CIRCUIT ADJUSTMENT
(AUDIO
SECTION)
L
SETTING
Dolby NR Switch: off
POSITION
Dubbing Spaad: Normal
OF SWITCH
Deck 1 Tapa Salector Switch: 12Ogs
AND KNOB
Deck 2 Tapa Selector Switch : Normal
Source Switch: LINE
ITEM INPUT
ADJUST-
MENT
POINT
REMARKS (CHECK)
BIAS
OSCILLATION
FREQUENCY
L301
Metal: 105 i 5 kHz
BIAS
CURRENT
L: VR301 Normal: 15.OV
R: VR302 (Metal: 38 + 4V)
002: 22 f 3V)
ERASE
___ Matal: 38.5 i 4V
CURRENT
DECK 1
Test tape
L: VRlOl 1. Normal: 520 mV
PLAYBACK
MTT-150
R : VR201
SENSITIVITY
2. Sea that the segments
of up to OdE are light-
ing up.
tf the segments of up
to -3d8 or of up to
+3d8 are ttghtlng up,
take the procedures
shown m the Table l l
DECK 2
Test tape
See that the electron,c
‘LAY BACK
MTT-150
SENSITIVITY
voltmeter reading is
wlthln the range from
463 mV to 583 mV.
If not, take the
procedures shown in
the Table ‘2
qECORD/ Non-
1. Adjust the record level
‘LAY BACK
recorded
control knobs so that
;ENSlTlVlTY tape
L- VR102
the electronic volt-
MTT-502
R: VR202
meter reads 370 mV.
1 kHz,
2. Playback the normal
-13dBV
tape recorded and ad-
(-3dB REC)
just the semt-variable
resistor so that the
electronic voltmeter
reads 370 mV.
Table +l
Lighting wmants
UP to -3dB
UP to +3d8
Table l 2
Procedures
Cut the resistor R197 or R297.
Cut the resistor R196 or R296.
Voltmeter reads
More than 583mV
Less than 463mV
Proudurr
Cut the resistor R114 or R214.
Cut the resistor R113 or R213.
TPlOl 01
TP201
Frewencv Counter
L-=-l
I
GND
J
Figure 9-l BIAS OSCILLATOR FREQUENCY
/BIAS CURRENT
Record Mode
Figure 9-2 ERASE CURRENT
Electronic
Voltmeter
Playback Mode YE k]
I-
- GND 1 -
]
Figure 9-3 DECK l/DECK 2 PLAYBACK SENSITIVITY
Low Frequency
Oscillator
LINE
Figure 9-4 RECORD/PLAYBACK SENSITIVITY
-9-