Sharp GF-575H

1.
2.
Record Amplifier Erase Current Check
(Refer to Figure 16-1)
Connect an Electronic Voltmeter to both ends of resistor
R317.
Place the unit in record mode, and set the deck 2 tape
selector switch SW104 to METAL position.
. Check that the Electronic Voltmeter is reading 160mV and
more.
Oscilloscope
Record mode
Erase Head
Figure 16-1
TAPE SPEED ADJUSTMENT
For Normal Speed Operation:
. Connect a wow/flutter meter to the Line Output Socket
J301D (or J301E) across a 100Kohm resistor.
. Play a test tape (TEAC, MTT-111, 3kHz prerecorded) — at
its middle part but not at its start or end point.
. Adjust the semi-variable resistors (VR902 for the deck 1
and VR903 for the deck 2) on the mechanism P.W.B. so
that the output frequency is 2985 to 3015 Hz for the deck
1 and 2970 to 3000 Hz for the deck 2.
For High Speed Operation:
At the deck 1;
Ts
2.
Place the unit in high speed dubbing mode with a test tape
(TEAC, MTT-118, 1kHz prerecorded) loaded in the deck 1.
Adjust the semi-variable resistor (VR901) on the mecha-
nism P.W.B. so that the output frequency is 1990 to
2010 Hz on the wow/flutter meter.
At the deck 2;
1.
Short the base and emitter (test pin) of the transistor 0911
on the mechanism P.W.B. Place the unit in high speed
dubbing mode with a test tape (TEAC, MTT-118) loaded in
the deck 2.
2. Adjust the semi-variable resistor (VR904) on the mecha-
nism P.W.B. so that the output frequency is 1980 to
2000 Hz on the wow/flutter meter.
Note:
For the adjustment, arrange the deck 1 and deck 2 to
provide the same speed.
¥ i8g10
<r tA FE Frw'g
Figure 16-2
O-vRs01
B-vR\502
VR272 Figure 16-4
VR271
Figure 16-3
CIRCUIT CONSTRUCTION
It is possible to select either normal tape speed or high tape
speed when you perform dubbing from the deck 1 to the deck
2 and the high speed is twice as fast as the normal speed.
£46=