Sharp SC-103H Service Manual page 19

13. GENERAL FREQUENCY CHARACTERISTIC CHECK (Refer to Fig. 42)
Oscilloscope
Attenuater
V.T.V.M
CR. OSC —20dB RECORD mode PLAY BACK mode
Speaker
iv
Jack
LINE IN Jack
Tape Dummy
Figure 42
1) Set Mode Selector Switch (SW-8) at "CASSETTE PLAY".
3) Set RLF. Switch (SW-4) at "A".
4) Insert the cassette tape (not recorded) into the unit and set it at RECORD mode.
14, DIN INPUT/OUTPUT SENSITIVITY CHECK (Refer to Fig.43)
CR.OSC V.T.V.M
(kHz RECORD mode DIN Sock
Attenuater
(Out sri
~ 26 dB
(A)
CR.OSC V.T.V.M
Attenuater
—20dB
(B)
DIN Socket SPEAKER
(Input) Socket aon
Figure 43
(A) 1) Set Mode Selector Switch (SW—8) at "CASSETTE PLAY".
2) Insert the cassette tape into the unit and set it at RECORD mode.
3) Input -26dB, 1kHz signal to LINE IN Jack (SO701).
4) Connect 50K ohm dummy resistor to DIN Socket (Output terminal).
It is normal if voltage at both ends is within the range -34 dB.
(B) 1) Pull out Record Monitor control knob.
2) Input 1kHz signal to DIN Socket (Input terminal).
3) Connect 8 ohm (45%, 10W) dummy resistor to Speaker jack (SO704, SO705). and VTVM to the ends.
4) Adjust, Input Signal Level so that V.T.V.M. reading 3,3V. Henceforth, make the input level -20dB.
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