Akai X-360

Normal
b) Reverse
® --> 07———Reverse “‘OFF”’ (Button or Dial)
REV.1, REV2 “OFF” (Main Mo-
1OmS-- - ——-- tor starts mormai rotation.)
—7---RT “ON”
20mS
|
ota
oe
C552
charges(220zF).
f----- REV.3 “OFF”
30ms+.t—i—i—t*s
RT.
“OFF”
~ -4----PT. “ON”
40mS
>—P.T. kept ‘‘ON”’ condition.
'
1.38 -—f----REV. H “OFF”
(P.B. Head held up to normal
| position.)
'
4s = Ts PT. “‘OFF”’
4.015S -+-------- QT, MAG. BRK. PR are ‘‘ON’
time
Fig. 9
Sequence of operation when the FORWARD Button is
depressed during REVERSE PLAY, or when the White
Mark on the Tape Count Meter reaches the “O’’ Mark on
the Tape Count Scale used for Automatic Reverse is as
follows, assuming this is point “B”.
Reverse Circuit current is cut off at point(B), but REV1
and REV2 remain engaged for approximately 10 milli-
seconds. As REVI is disengaged, the Main Motor starts
rotating in the Normal direction. When the current in
the Reverse Circuit is cut off, the 33 uF Condenser,
which is series connectes to the RT Relay and charged
during Reverse Play, is discharged through the RT Relay
Coil and the 650 2 Resistor. The Discharge Time is
about 28 milliseconds. Thus, the RT Relay remains
engaged approximately 13 milliseconds. (See Figure 9)
28
RT1 normally open contact is closed and Condenser
C552 (220 uF) is charged in approximately 5. milli-
seconds.
As RTI closes, current starts flowing to the PT Relay
Coil. As RT1 opens, C552 discharges and the PT Relay is
engaged 35 milliseconds later, and continues to be
operative for about 4 seconds, after which it is engaged.
CS51 (1000 uF) discharges current to the REV.H
Solenoid Coil. in approximately 1.3 seconds after point
(B), the REV.H is disengaged and the Playback Head
raises to its Normal Play position.
As the PT Relay is disengaged, current flows to OT and
MAG Relays and to BRK and PR Solenoids through the
normally closed contacts. After approximately 15 milli-
seconds, the QT and MAG Relays and the BRK and PR
Solenoids are actuated (“‘ON’’), and tape travel starts in
the Normal direction.
8. Comput-O-matic
a) By depressing the Set Button (SW25-1) with no
input signal applied to Line Input or
Microphone Jacks, current flows to the
Comput-O-Matic Motor through the Relay
(MH2PM-0) (a normally closed contact) and the
Microswitch (SW92-1), causing the Motor to
rotate in the direction indicated by the blue
line in Figure 10.
The Motor Shaft is connected to the Comput-
O-Matic Volume Control Shaft by gear
mechanism. When the Motor rotates in the
direction indicated by the blue line, the
Volume Control turns toward the upper limit
(maximum). When the Volume Control! reaches
the upper limit, Microswitch SW92-1 is cut off
by the cam attached to the Volume Control
Shaft, cutting the flow of current to the Motor,
thus, stopping the Motor.
As current is cut off, Bias Voltage is applied to
Transistar TR70-8, through R70-23 and
R70-22, actuating TR70-8. As TR7/0-8 is
actuated (‘ON’) collector current flows
through the Relay Coil MH2PM-O, engaging the
Relay. However, when no input signal is
applied, current does not flow to the Motor
because Transistor TR70-7 is inoperative
(OFF), as shown in Figure 10.
b) Under conditions as described above, but when
input signals are applied to the Line Input or
Microphone Input Jacks (for input signals level
of O VU or greater) the function of Transistors
are as shown by the red print in Figure 10. As
‘TR70-7 is actuated, TR70-7 collector current
flows through the Motor, causing the Motor to
rotate in the direction indicated by the red
arrow in Figure 10.
As the Motor rotates in the direction indicated
by the red arrow, the Volume Control rotates
from the upper limit toward the lower limit
(minimum). The input signals applied to the