Fig. 2
Arrangement of components on the PCB
Fig. 1
Schematic diagram
GND
1
2
S1
1
2
S2
1
2
S3
1
2
S4
S1
S2
S3
S4
ULN2003AN
GND
+12V
+12V
I1
1
I2
2
I3
3
I4
4
I5
5
I6
6
I7
7
O1
16
O2
15
O3
14
O4
13
O5
12
O6
11
O7
10
CD+
9
GND
8
IC3
2
1
REL1
O
S
P
2
1
REL2
O
S
P
2
1
REL3
O
S
P
2
1
REL4
O
S
P
OUT1
OUT2
OUT3
OUT4
P1
P2
P3
P4
10k
+5V
MEGA8
GND
100nF
GND
R1
PB5(SCK)
19
PB7(XTAL2/TOSC2)
10
PB6(XTAL1/TOSC1)
9
GND
8
VCC
7
GND
22
AREF
21
AVCC
20
PB4(MISO)
18
PB3(MOSI/OC2)
17
PB2(SS/OC1B)
16
PB1(OC1A)
15
PB0(ICP)
14
PD7(AIN1)
13
PD6(AIN0)
12
PD5(T1)
11
PD4(XCK/T0)
6
PD3(INT1)
5
PD2(INT0)
4
PD1(TXD)
3
PD0(RXD)
2
PC5(ADC5/SCL)
28
PC4(ADC4/SDA)
27
PC3(ADC3)
26
PC2(ADC2)
25
PC1(ADC1)
24
PC0(ADC0)
23
PC6(/RESET)
1
IC2
C5
IR
LED1
LED2
LED3
S1
S2
LED4
LED5
S3
S4
P1
P2
P3
P4
SYN
SEL
PK1
PK2
PK3
PK4
100uF
100nF
100nF
+5V
GND
100uF
+12V
1N4007
78L05
C2
C4
C3
C1
D1
GND
VI
3
2
VO 1
IC1
+
+
VCC
GND
1k
1k
1k
+5V
1k
R4
R5
LED1
LED2
LED3
R6
LED4
R7
LED1
LED2
LED3
LED4
GND
+5V
1
2
3
4
5
SV1
1
2
3
4
5
SV2
1
2
3
4
5
SV3
SEL
PK1
PK2
PK3
PK4
1k
10k
+5V
R3
R2
SYN
S
2
Schematic diagram of the switch is shown in Figure 2.
Start by soldering resistors and other small
components onto the board and finish by fitting
electrolytic capacitors, screw connectors and relays. A
properly assembled circuit, once the configuration
jumpers have been properly set, is immediately ready
for operation. Changing the operating configuration
of a particular relay is possible at any time during
system operation and takes place independently for
each of the 4 channels.
