Akai VS-2EGN Service Manual page 76

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5) Regulated 5V
The power supply for the micro-computer uses a dif-
ferent winding (secondary side) from the one used with
the VIR drive system. This arrangement helps to mini-
mize the effect of possible trouble in the mechanical sec-
tion on the micro-computer system. (Micro-computer-
independent PWR SUPPLY)
6-3 CONTROL SYSTEM
Each VTR mode is controlled by a micro-computer, but
the most of the circuitry is controlled through the or via
the power supply. With VS-2, the micro-computer and
power supply section are installed on the same PCB, and
the power supply and control line to each block are pro-
vided on a per-connector basis.
6-4 POWER SUPPLY CIRCUIT
Fig. 7-102 is the block diagram of the power supply
circuit with each power output given in detail.
6) IDL 33V
This is the supply which provides the basis for the tuning
voltage to be generated at the operation PCB. AC19V
is doulbe-voltage rectified at D9, D3, C9 and C26, and
smoothed at D4 and C10. With DC45V thus obtained,
33V regulated at IC4 (uPC574J) is generated.
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| MAX 600m ORUM MOTOR POWER
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POWER TRANS
UNREG 19V
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'Service Manu:
Fig. 7-102 Block Diagram of Power Supply Circuit
ral VS-2EGN
73