Akai GX-2800D-SS

IV. MECHANISM ADJUSTMENTS
SERVO CONTROL
AMP PC. BOARD-
LI VI2031SC-O1
VR 202 2KB
1. TAPE SPEED ADJUSTMENT
10
(Servo Control Amp. Adjustment)
1) Connect: a frequency counter to the Line Out-
puts as shown in Fig. 1.
2) Depress 3-3/4 ips (9.5 cm/sec.) Tape Speed Selec-
tor Switch and playback a 1,000 Hz pre-recorded
test tape.
3) Adjust the core of coil L1 (V1023SC-01) shown
in Fig. 8 to obtain a frequency counter indica-
tion of 500 Hz +1%.
4) After the 3-3/4 ips (9.5 cm/sec.) tape speed
adjustment has been completed, depress the 7-1/2
ips (19 cm/sec.) Tape Speed Selector Switch and
adjust Servo Control P.C. Board semi-fixed resistor
VR202 (2 kB) shown in Fig. 8 to obtain a
frequency counter indication of 1,000 Hz +1/
—0.5%.
NOTE: When making tape speed adjustment, it is
necessary to make the low speed (3-3/4 ips)
adjustment first.
SYSTEM CONTROL.
PC. BOARD
VRIO] IOKB
VR102 IOKB
Fig. 8
2. DIRECT FUNCTION TIME CONSTANT
ADJUSTMENT
1) FWD @ REV Time Constant
Adjust System Control P.C. Board semi-fixed
resistor VR101 (30 kB) shown in Fig. 8 so that
when the machine is switched from FWD to REV
mode or. from REV to FWD mode, the pinch
wheel separates from the capstan in about 3
seconds.
2) Adjust System Control P.C. Board semi-fixed
resistor VR102 (10 kB) shown in Fig. 8 so that
when the mackine is switched from F.FWD or
RWD to FWD or REV mode, the time constant
is about 1.5 seconds.
NOTE: When making adjustments outlined in Items
2. 1) and 2. 2) above, when the machine is
switched from the various modes to FWD
or REV, confirm that correct capstan motor
(servo motor) revolutions are reached by
the time the pinch wheel contacts the
capstan.