WamBlee W400 MOB, Service Manual

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dB range.
4.10 Power supply circuit
The power supply system is assembled by:
•
Q10 is the main switch device and is controlled by R24 and R25. Ground the resistor R25,
the switch Q10 go closed. The R25 may be grounded via D6 (from the sea sensor)and
from Q9 (under microprocessor control).
When the W400 MOB is under TEST mode, the power supply control is under microprocessor
using Q9, instead when the unit is under ARMED mode, the power is controlled via D6. Follow
the Q10 switch, is placed a linear voltage regulator U10 , a 3.3 Volts regulator for logic supply.
4.11 Microprocessor unit
The microprocessor unit is U1; all operation are made from this unit and all clock signal are
generated using a internal oscillator (no external clock signal). Reset operation and Brown
voltage detection are inside. The software can be upgraded using the P5 connector.
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