– 54 –
1. Receiver Circuit
● The light receiver unit receives the infrared signal from the wireless remote control. The receiver amplifies
and shapes the signal and outputs it.
2. Buzzer Circuit
Fig. 3-1 Buzzer Circuit
Sound wave
Metal diaphragm
V
Pizoelectric element
V
Fig. 3-2 Buzzer Operation
Microcomputer
Buzzer output
BZ
12V
0V
R722
Q722
30
BZ
● When the buzzer sounds, an approx.
3.9kHz square signal is output from buzzer
output pin of the microcomputer. After
the amplitude of this signal has been set
to 12Vp-p by a transistor, it is applied to
the buzzer. The piezoelectric element in
the buzzer oscillates to generate the
buzzer’s sound.
DESCRIPTION OF MAIN CIRCUIT OPERATION
MODEL RAI-25NH5A, RAI-35NH5A, RAI-50NH5A
Fig. 2-1
30
0V
5V12V
R411
R412
R413
0V
13
RECEIVER I/P
Microcomputer
R611
C414
IRR
GND
V
out
V
DD
C611
C413
C412
C411
ZD411