WamBlee W400 MOB, Руководство по обслуживанию

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visible the graphics as figure 5, with a minimum performance of:
•
Voltage peak-peak = min 7 Volts (symmetric to 0 Volts)
•
DC voltage = 0 Volts
•
Frequency shall be variable according sweep mode.
4.6 Verify the beeper loudspeaker
The beeper loudspeaker signal is generated via microprocessor with clock divider operation and
value reload. There are non tools or adjustment required to set or calibrate the tone frequency
and level, but its possible to verify some hardware point if performance in the previous chapters
are not satisfied.
To verify the beeper loudspeaker signal, set the oscilloscope with these parameters:
•
Amplitude = 2 Volts / div.
•
Offset level = 6 Volts
•
DC Coupling
•
Time Base = 2 ms / div
•
Probe Hi Z 10:1
Connect the probe to ground and the tip on Q1 base node (see TP2 on Figure 2) and press the
TEST pushbutton (you can leave the W400 MOB in TEST mode). For 10 seconds shall be visible
the graphics as figure 5, with a minimum performance of:
•
Voltage peak-peak = min 8 Volts
•
DC voltage ref. = 0 Volts
•
Frequency shall be variable according beep sequence.
4.7 Verify the sea sensor switch
The sea sensor activation is a standard operation performed when then W400 MOB is activated
via Man Over Board situation. The sea sensor do:
•
Maintaining polarized a PNP transistor (Q3) inside PCB board.
•
When wather touch then sea sensor, a small current flow outside the PNP base.
•
A RC net (R18/C6) charge a N-FET circuit (Q4).
•
A positive reaction is made from Q5 to maintaining Q4 close until power is removed
(moving the main knob to OFF position).
To verify the sea sensor circuit, please:
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