Receiver Module Functional
LM35 (Linear temperature sensor IC) through a power amplifier and voltage change as a form of high frequency. To signal through the AC power cord.
For the receiver circuit and display module will receive the high frequency AC power cord and decode out to be the actual temperature figures with digital IC No. CD4553 Three-digit BCD Counter IC) and IC-CD4511 (BCD-to-7-Segment Latch / Decoder / Driver IC).
Electronic Part List
Receiver Module
R1 100K 1/4W
C1,C2 47nF 400V
R2 1K 1/4W
C3,C7 1nF 63V
R3,R4,R6-R8 12K 1/4W
C4 10nF 63V
R5 47K 1/4W
C5,C6,C10 220nF 63V
R9-R15 470R 1/4W
C8 1000uF 25V
R16 680 1/4W
C9 100pF 63V
D1,D2,D5 1N4148
D3,D4 1N4002
D6-D8 Common-cathode 7-segment LED mini-displays
IC1 403
IC2 4518
IC3 78L12
IC4 4017
IC5 4553
IC6 4511
Q1 BC239C
Q2-Q4 BC327
L1 Primary (Connected to C1 & C2): 10 turns
Secondary: 100 turns
Wire diameter: 0.02mm. enameled
Plastic former with ferrite core. Outer diameter: 4mm.
T1 220V Primary, 12+12V Secondary 3VA Mains transforme
Remote Module Functional
The frequency pulses from the wall and safely isolated by C1, C2 and L1 are amplified by Q1, diodes D1 and D2 of the peak limit his admission. The pulses are filtered by C5, IC1b square, divided by 10 in IC2B and sent for final countdown clock input of IC5. IC4 is the time base generator: it provides IC1b and reset pulses to the making and IC5 locks and opening time of IC5 at 1Hz frequency. It is powered by a 5Hz square wave obtained from the frequency 50Hz sector Retrieved from T1 secondary, squared and divided by 10 in IC1C IC2A. IC5 readers across the cathodes scenes Q2, Q3 and Q4 with a rate determined by frequency multiplexing C7. Readers also shows three anodes in parallel by the BCD to 7 segments decoder IC6. In summary, the input pulse power on, say, 2kHz frequency be divided by 10 and displayed as 20.0 ° C
Remote Module
R1,R3 100K 1/4W
C1 220nF 63V
R2 47R 1/4W
C2 10nF 63V
R4 5K 1/2W Trimmer Cermet
C3 1uF 63V
R5 12K 1/4W
C4,C6 1nF 63V
R6 10K 1/4W
C5 2n2 63V
R7 6K8 1/4W
C7,C8 47nF 400V
R8,R9 1K 1/4W
C9 1000uF 25V
D1 1N4148
IC1 LM35
D2,D3 1N4002
IC2 LM331
D4 Red LED
IC3 78L06
Q1 BC238
Q2 BD139
L1 Primary (Connected to Q2 Collector): 100 turns
Secondary: 10 turns
Wire diameter: 0.02mm. enameled
Plastic former with ferrite core. Outer diameter: 4mm.
T1 220V Primary, 12+12V Secondary 3VA Mains transformer