Skema Rangkaian Kipas Pendingin Otomatis

Alat atau benda elektronik yang sering bekerja tentunya akan menjadi panas. Ketika panasnya berlebih maka dibutuhkan pendingin misalnya Kipas. Nah, pendingin manual akan terus menerus bekerja tanpa henti agar alat tidak menjadi panas. Kalau pendingin terus menerus bekerja kemungkinan besar pendinginnya akan cepat rusak dan listrikpun akan boros. Oleh karena itu kita memerlukan sebuah pendingin otomatis atau kipas pendingin otomatis. Kipas Pendingin Otomatis ini akan bekerja ketika alat menjadi panas dan akan berhenti bekerja ketika alat dingin kembali atau dalam keadaan normal.
Berikut ini adalah Skema rangkaian kipas pendingin otomatis:

Daftar Komponen:
Resistors 1/4W + 5%
R1, R8, R9, R10, R11_________1K
R2________________________300ohm
R3________________________15K
R4________________________10K
R5________________________5.6K
R6________________________4.7K
R7________________________100K
VR1_____________500 ohms
C1, C2_______100uF 16V Electrolyte
D1, D2______1N4148___ 75V 150mA Diodes
IC__________LM334Z_constant current source
and temperature sensor
IC1_________LM324_Quad OP-AMP
IC2_________CD4027_
Q1__________C9013__PNP transistor
Other parts
Relay____12V______________1 pcs.
Socket 16 pin_______________1 pcs.
Socket 14 pin_______________1 pcs.
LED______________________1 pcs.
Kipas 12V________________1 pcs.


Dasar sirkuit untuk sensor suhu ini menggunakan IC LM334z. Dalam penerapannya IC sensor suhu LM334z ini cukup direkatkan saja pada heatsink atau pada alatnya dengan menggunakan silicon. Kaki IC sensornya menggunakan kabel menuju rangkaian. Untuk lebih detilnya kunjungi aja ke sumbernya eleccircuit.com

Proyek ini bisa digunakan misalnya untuk pendingin Heatsink pada rangkaian elektronika seperti Amplifier, Komputer, Adaftor, Pemancar Radio dan lain lain.

Read More

Skema Rangkaian Detektor Logam | Metal Detector

Saya telah membahas tentang Rangkaian Detector Emas sederhana sebelumnya, namun tentunya ada kekurangan baik dalam kepekaan juga suara yang dihasilkan yang kurang jelas. Ada sahabat Facebook yang telah mencoba rangkaian Detector Logam sederhana yang saya berikan pada postingan sebelumnya yang ternyata Harmonic di radionya katanya kurang begitu kuat. Berbeda dengan Rangkaian yang saya suguhkan kali ini hasilnya yang pasti tidak akan mengecewakan.

Skema rangkkaian Detektor Logam

Loop detektor logam

Rangkaian Detektor Logam ini dibangun dengan 2 Oscillator, keduanya disetel pada frekuensi yang sama. Hasil dari dua osilator ini kemudian dicampur dalam mixer yang hanya menghasilkan perbedaan. Berarti, jika kedua osilator berada pada frekuensi yang sama, tidak ada yang terdengar di speaker. Untuk memulainya anda jaga detektor di udara bebas jauh dari benda logam. Gunakan kontrol tuning untuk mengaturnya. Setelah itu mulailah menempatkan detektor di sekitar benda logam dan Anda akan melihat bahwa "Nol pemukulan" semakin terganggu dan nada audio dari speaker terdengar. Wow, detektor telah menemukan logam!

Sirkuit:Kedua osilator yang dibangun menggunakan MPF102 atau J310 FET. Mixer adalah BF998 ganda MOSFET gate
IC audio LM386 sebagai amplifier untuk menguatkan suara.Selamat mencoba!

Source: http://nina.foxdelta.com/detector.html.

Read More

Skema rangkaian pengontrol suhu dengan LM35DZ

Sebelumnya kami telah memberikan postingan mengenai skema rangkaian penetas telur otomatis. Rangkaian ini cara kerjanya tidak jauh berbeda yakni untuk mengontrol suhu ruangan agar konstan pada suhu tertentu. Rangkaian ini outputnya menggunakan relay yang bisa diaplikasikan misalnya untuk mesin penetas telur otomatis, atau untuk menggerakan kipas angin di ruangan, atau untuk pengontrol suhu di mobil. Rangkaian ini memakai sensor suhu LM35DZ.  Ketika LM35DZ mendeteksi suhu lebih tinggi dari tingkat preset (ditetapkan oleh VR1), maka relai akan bekerja. Ketika suhu turun di bawah suhu preset, relay akan mati. Rangkaian dapat didukung oleh AC atau DC 12V pasokan daya atau baterai (100mA min.).

Skema rangkaian

Skema rangkaian pengontrol suhu LM35DZ

Layout PCB

Layout pcb pengontrol suhu LM35DZ

Daftar komponen:
IC1 : LM35DZ
IC2 : TL431
IC3 : LM358
LED1 – 3mm or 5mm LED
Q1 – General purpose PNP transistor ( A1015,…) with E-C-B pin-out)
D1, D2 — 1N4148
D3, D4 — 1N400x (x=2,,,,.7)
ZD1 — Zener diode, 13V, 400mW
Preset (trim pot) : 2.2K (Temperature set point)
R1 – 10K
R2 – 4.7M
R3 – 1.2K
R4 – 1K
R5 – 1K
R6 – 33Ω
C1 – 0.1 µF ceramic or mylar cap
C2 – 470 µF or 680 µF electrolytic cap. (16V min)
Relay – DC12V DPDT, Coil = 400 Ω or higher

Sumber: http://www.escol.com.my

Read More

Skema rangkaian pendeteksi debit air

Terkadang kita pusing memikirkan air yang terus mengalir gara gara tidak mengetahui air didalam tangki sudah penuh sehingga terjadi pemborosan dan terkadang kita pusing ketika kita membutuhkan air dengan segera ternyata air di dalam tangki sudah kosong karena kita lupa menyalakan pompa air atau membuka kran pengisian. Oleh karena itu rangkaian sederhana ini bisa memberikan jawaban itu dan anda akan dibikin nyaman karenanya. Skema Rangkaian pendeteksi debit air ini akan otomatis memberitahu anda apabila tangki air anda kosong dengan bunyi buzzer. Dan apabila tangki sudah penuh anda akan diberitahu dengan lampu yang menyala.

Skema rangkaian pendeteksi debit air

Cara kerja rangkaian:
N1 pemicu Schmitt bekerja sebagai osilator dan menghasilkan frekuensi sekitar 1 kHz. Jika di dalam tangki masih cukup air, maka tegangan alternatif pergi dari elektroda A C. elektroda ke Setelah diperbaiki dari dioda D1 dan D2, di pin 13 dari N4 mencapai melalui D3 a "0" logis. Dengan ini, suara osilator N4 dan buzzer terputus.

Jika tingkat air tetes ke sedemikian rupa sehingga elektroda C tidak lagi dalam kontak dengan air, maka pemblokiran N4 ditangguhkan dan buzzer mulai terdengar secara berkala. Durasi alarm ditentukan oleh kapasitor osilator N3 dan C6. Alarm akan berhenti secepat tangki mengisi dan C elektroda lagi dalam kontak dengan air. Jika tombol S1 beroperasi sebelum mengisi D5 lampu LED secepat air mencapai elektroda B. D5 mati setelah sekitar 10 detik tidak ada tegangan yang kuat.

Karena pemantauan tingkat dibuat dengan sinyal AC, oksidasi elektroda berkurang. Tegangan suplai bisa antara 5 dan 15 V. Jika Anda memilih tegangan lebih rendah dari 9 V, elektroda C permukaan harus jauh lebih tinggi dibandingkan dengan elektroda B. Hal ini diperlukan karena ada kehilangan sinyal dari C elektroda dalam D1 dioda. .. D3.

Read More

Pengatur Suhu Ruangan Elektronik

Skema Rangkaian Pengatur Suhu Elektronik ini dirancang menggunakan L121 sirkuit terpadu diproduksi oleh SGS THOMSON. Sirkuit ini dapat digunakan untuk mengatur suhu di dalam kendaraan atau pada rangkaian Power Suplay. Rangkaian ini menggunakan tegangan suplay 12 Volt. Rangkaian elektronik ini memungkinkan suhu yang diinginkan di dalam ruangan yang bervariasi antara dua batas. Suhu ruangan dideteksi oleh NTC termistor (koefisien temperatur negatif) dengan nilai nominal 47 K pada 25 ° C.

Penurunan tegangan pada termistor yang digunakan untuk mengatur tingkat ke salah satu input dari L121 penguat operasional. Ambang ini menentukan output penguat operasional sirkuit beralih urutan integrasi. Potensiometer P2 menyesuaikan input kedua dari penguat operasional yang sama dan digunakan untuk meresepkan suhu di mana sirkuit masuk ke dalam operasi.

Bila suhu di dalam ruang meningkat, resistansi thermistor menurun, dan akan menyebabkan tegangan di pin 3 menurun. Setelah beberapa waktu, himpunan P2 tercapai, menyebabkan rangkaian logika tipping dari IC1. Ini akan menentukan input ke T1 konduksi transistor, yang akan menghidupkan kipas angin sehingga menghasilkan udara dingin. Setelah suhu turun pada batas nilai yang ditentukan oleh P1, rangkaian kontrol akan mematikan kipas angin kembali.

Read More

Skema Rangkaian Saklar Cahaya Otomatis

Skema Rangkaian Saklar Cahaya Otomatis ini sangat cocok untuk memberi penerangan sementara ketika suatu ruangan menjadi gelap akibat putusnya aliran listrik atau terjadi korsleting dan akan memberi penerangan selama jangka waktu tertentu antara 1 jam sampai dengan 5 jam bisa diatur.
Skema rangkaian:

Skema Rangkaian Saklar Cahaya Otomatis

The switch is a semiconductor relay S202DS2 and the oscillator is 4060.


Cara kerja rangkaian:
From the moment that T4 and T5 are opened, relay’s LED start to light and powers the lamp. As soon as one of the transistors is blocked the lamp will go OFF. The phototransistor T3 will be the one that blocks T5 if there is light that falls on T3. The T2′s base-emitter junction is connected in parallel with T3 and so will be blocked as long there is light. T2 will continuously resest IC1 whose counter outputs will be in “0″ state.

When the night falls R7 provides base current for T2 and the transistor starts to conduct. The counter can now starts to count the impulses from the internal oscillator and in this time the light will bulb will stay lit. After a time, when the output of Q13 goes in state “1″ T4 is blocked. This causes the relay’s LED to go off and the lamp too.

There is no need for external power supply because the light sensor switch is powered directly from the 220V mains. D1 … D5 diodes rectifies the voltage and C4 filters it.
C5 is working as a resistor so will need to have the working voltage of minimum 400V but the 630V is preferable.

S202DS2 is a Triac-Full-Wave-Output Optocoupler produced by Sharp Electronics in a TO-220 package.
The maximum peak-to-peak voltage is 600V, max on-state current is 8 Ampere and the input trigger current is 8 mA.

Caution! This circuit is powered directly from 220V. Attention will be given for appropriate isolation of the switch block.

Read More

Rangkaian Detektor Sinyal Handphone

Ketika Handphone anda dalam keadaan Silent atau Diam karena sesuatu hal yang mengharuskan HP kita tdk boleh berbunyi, misal ketika sedang melakukan rapat atau saat melakukan Sholat atau ketika berada di tempat ibadah maka kita bisa mengetahui adanya panggilan masuk atau ada sms dengan sinyal cahaya yakni dengan menggunakan Alat Detektor Sinyal Handphone. Alat ini akan bekerja atau menyala ketika ada sinyal RF dari Handphone. 

Rangkaian Detektor Sinyal HP

Cara Kerja Rangkaian:
Op-amp IC CA3130 (IC1) is used in the circuit as a current-to-voltage converter with capacitor C3 connected between its inverting and non-inverting inputs. It is a CMOS version using gate-protected p-channel MOSFET transistors in the input to provide very high input impedance, very low input current and very high speed of performance. The output CMOS transistor is capable of swinging the output voltage to within 10 mV of either supply voltage terminal.
Capacitor C3 in conjunction with the lead inductance acts as a transmission line that intercepts the signals from the mobile phone. This capacitor creates a field, stores energy and transfers the stored energy in the form of minute current to the inputs of IC1. This will upset the balanced input of IC1 and convert the current into the corresponding output voltage.
Capacitor C4 along with high-value resistor R1 keeps the non-inverting input stable for easy swing of the output to high state. Resistor R2 provides the discharge path for capacitor C4. Feedback resistor R3 makes the inverting input high when the output becomes high. Capacitor C5 (47pF) is connected across ‘strobe’ (pin and ‘null’ inputs (pin 1) of IC1 for phase compensation and gain control to optimise the frequency response.
When the cell phone detector signal is detected by C3, the output of IC1 becomes high and low alternately according to the frequency of the signal as indicated by LED1. This triggers monostable timer IC2 through capacitor C7. Capacitor C6 maintains the base bias of transistor T1 for fast switching action. The low-value timing components R6 and C9 produce very short time delay to avoid audio nuisance.
Assemble the cell phone detector circuit on a general purpose PCB as compact as possible and enclose in a small box like junk mobile case. As mentioned earlier, capacitor C3 should have a lead length of 18 mm with lead spacing of 8 mm. Carefully solder the capacitor in standing position with equal spacing of the leads. The response can be optimised by trimming the lead length of C3 for the desired frequency. You may use a short telescopic type antenna.
Use the miniature 12V battery of a remote control and a small buzzer to make the gadget pocket-size. The unit will give the warning indication if someone uses mobile phone within a radius of 1.5 meters.

Source:  http://electroschematics.com

Read More

Rangkaian Pendeteksi kadar Air dalam Pot Tanaman

Rangkaian Tester kadar air pot tanaman ini sangat berguna sekali bagi yang suka menanam tanaman dalam pot apakah masih cukup kadar airnya atau kurang. Sehingga anda tidak usah kotor kotoran untuk mengetahui kadar air dalam pot. Rangkaian ini sangat sederhana sekali karena hanya membutuhkan beberapa komponen saja. Untuk Probe gunakan bahan logam seperti paku atau kawat.

Cara kerja dan pengetesan:
Untuk mencobanya anda siapkan pot yang berisi tanah kemudian berilah air secukupnya kemudian masukkan/tusukkan kedalam tanah di pot dan setel Potensiometer sampai menyala. Kemudian cobakan probe dimasukan ke tanah yang masih kering atau kadar airnya rendah, lampu Led seharusnya tidak menyala. Anda perlu menyesuaikan potensiometer 47k untuk mengatur tingkat di mana LED akan menyala.

Read More

Low Voltage Battery Monitor

Rangkaian Monitor Tegangan Rendah ini sangat diperlukan sekali untuk keamanan dan perlindungan terhadap kerusakan peralatan anda terutama untuk mobil anda. Buzzer akan berbunyi dan Lampu Led akan menyala ketika Baterai mobil anda dalam keadaan tegangannya sangat minim. Meskipun rangkaiannya sangat sederhana namun bisa melindungi mobil anda dari kerusakan yang sangat merugikan.

Skema Rangkaian Low Voltage Battery Monitor

Component List:
R1, R3 2 1K 1/4W Resistor
R2 1 5K Pot
U1 1 LM339 Voltage comparator IC
D1 1 1N5233B Zener Diode
D2 1 LED
BZ1 1 Piezo Buzzer
MISC 1 Board, wire, socket for IC
Notes
1. The circuit will operate from 9V to 12V.
2. Adjust R2 until the alarm goes off at the correct voltage.
Source: http://www.ubmthai.com/leksoundsmf3/index.php?topic=6029.30

Read More

Rangkaian Sensor Parkir dengan Infra Merah

Skema Rangkaian Sensor Parkir dengan Infra Merah. This circuit can be used for an assist in parking the car near the garage wall backing up Pls. LED D7 illuminates Pls bumper-wall distance is about 20 cm., D7 + D6 illuminate at about 10 cm. and D7 + D6 + D5 at about 6 cm. In this manner you are alerted Pls approaching too close to the wall.

Car Parking Sensor circuit

All distances mentioned before can vary, depending on infra-red transmitting and receiving LEDs used and are mostly affected by the color of the reflecting surface. Black surfaces lower greatly the device sensitivity. Obviously, you can use this circuit in other applications like liquids level detection, proximity devices etc.

Note:

• The infra-red Photo Diode D2, should be of the type incorporating an optical sunlight filter: these components appear in black plastic cases. Some of them resemble TO92 transistors: in this case, please note that the sensitive surface is the curved, not the flat one.
• Avoid sun or artificial light hitting directly D1 & D2.
• If your car has black bumpers, you can line-up the infra-red diodes with the (mostly white) license or number plate.
• It is wiser to place all the circuitry near the infra-red LEDs in a small box. The 3 signaling LEDs can be placed far from the main box at an height making them well visible by the car driver.
• The best setup is obtained bringing D2 nearer to D1 (without a reflecting object) until D5 illuminates; then moving it a bit until D5 is clearly off. Usually D1-D2 optimum distance lies in the range 1.5-3 cm.

List Component of Car Parking Sensor circuit:

R1             : 10K
R2,R5,R6,R9    : 1K
R3             : 33R
R4,R11         : 1M
R7             : 4K7
R8             : 1K5
R10,R12-R14    : 1K
C1,C4          : 1µF/63V
C2             : 47pF
C3,C5          : 100µF
D1             : Infra-red LED
D2             : Infra-red Photo Diode (see Notes)
D3,D4          : 1N4148
D5-7           : LEDs (Any color and size)
IC1            : NE555
IC2            : LM324
IC3            : LM7812 

Read More

Rangkaian detektor kebohongan / Lie Detector Circuit Diagram

This lie detector circuit can be built in a few minutes, but can be incredibly useful when you want to know if someone is really telling you the truth. It is not as sophisticated as the ones the professionals use, but it works. It works by measuring skin resistance, which goes down when you lie.

Skema Rangkaian Detektor Kebohongan

Parts List:
R1 – 33K 1/4W Resistor
R2 – 5K Pot
R3 – 1.5K 1/4W Resistor
C1 – 1uF 16V Electrolytic Capacitor
Q1 – 2N3565 NPN Transistor
M1 – 0-1 mA Analog Meter
MISC – Case, Wire, Electrodes (See Notes)
Notes:

1. The electrodes can be alligator clips (although they can be painful), electrode pads (like the type they use in the hospital), or just wires and tape.
2. To use the circuit, attach the electrodes to the back of the subjects hand, about 1 inch apart. Then, adjust the meter for a reading of 0. Ask the questions. You know the subject is lying when the meter changes.

Source: Lie Detector circuit

Read More

Gold detector circuit

Rangkaian Detektor Emas. Here the very simple and easy build gold detector circuit. The circuit capable to sense gold or metal or coins from a distance of about 20cm, depending on the size of the object to detect.
The circuit oscillates at about 140kHz and a harmonic of this frequency is detected by an AM radio. You can simply tune the radio receiver until a squeal is detected.
When the search coil is placed near a metal object, the frequency of the circuit will change and this will be heard from the speaker of AM radio.

Below image is the construction of the circuit, you will see that the radio is placed on the hand stick of the complete detector.

Skema Rangkaian Gold Detector

Lay out Gold Detector-2

PARTS LIST:

1 - 220R (red-red-brown-gold)
1 - 47k (yellow-purple-orange-gold)
2 - 1n greencaps (102)
1 - 4n7 greencap (472)
1 - 10n greencap (103)
1 - 47u electrolytic
1 - BC 547 transistor
1 - slide switch
1 - 9v battery snap
1 - 9v battery
6.5m winding wire (gauge not critical)

Read More

Rangkaian Detektor Signal AF/RF

The following circuit of special functions to detect the presence or absence of signal AF / RF. This circuit is very simple so as to make it requires a relatively low cost. Detektor Signal AF/RF circuit based an audio amplifier and a loudspeaker with a switch input to the AF and RF signal. The whole device can be made as small as possible so that it can be included in a container to keep the peace.

Audio amplifier section in this series created by IC TDA 2822M, with a low-power stereo amplifier in 8-pin mini-DIP. This IC is used as a bridge cofiguration to minimize output power up to 250 mW, the loudspeaker is in use 4 ohm, 500mW. Current required is less than 10mA with a 3V battery voltage.

Skema Rangkaian Detektor Signal AF/RF

List Component

R1 : 22K
R2, 3, 4 : 4K7
C1 : 1n
C2, 6, 7 : 0,1uF
C3, 4 : 10uF/16V
C5 : 0,01uf
D1 : OA79
VR1 : 22K
IC 1 : TDA2822M
LS : 8 ohm 500mW


When the switch in the AF position, Signal input audio input working on AF amplifier (IC 1 pin 7) via a capacitor C2 and Potentiometer VR1. Capacitor C2 is always holding the input amplifier of the DC voltage and make it happen in the audio signal frequency. Input signal IC 1 can be arranged with the help of potentiometer VR1.

When switch on the RF position, the detector and demodulator circuit formed by capacitor C1, diode D1, and resistors R1 and R2 are connected to the input rangakaian. When the audio signal is detected it will be significantly strengthened in kerangkaian for. Signal detection is done by plugging in tactile (probe) on the legs of the existing components.

Read More

Rangkaian Pendeteksi Logam

Rangkaian Pendeteksi Logam

This simple metal detector requires alone a scattering of apparatus and an evening’s work. Congenital about a cmos4011 IC, is actual able-bodied and versatile. The 250 kHz advertence oscillator is congenital with two gates (U1/1 and U1/2), C1, R1 and P1. The chase oscillator uses alone one aboideau (U1/3), two capacitors and the chase coil. The outputs of the two oscillators are fed to the fourth aboideau acting as a mixer and filtered with C4.

After assembly, affix the headphones and boring about-face P1. The angle will get lower until it disappears. Continuing to circle P1 in the aforementioned administration will account the angle to acceleration again. The point at witch the angle is the everyman and disappears is alleged “zero beat”. If you can not get this aught exhausted abundance for the absolute about-face of P1 you may accept to baddest altered ethics for C1.
Turn P1 abutting to the aught exhausted position, again move the chase braid abreast a brownish object. The accent should change, depending on the admeasurement and ambit of the metal.
Note that this simple detector’s achievement is not commensurable to added avant-garde bartering products. It will alone ascertain about ample brownish altar at a abbreviate distance. Coins and added baby altar will be abundant harder to find!
Here the Beat-frequency Oscillator Simple Metal Detector Schematic Part List :

• U1: CD4011 (Quad 2-input NAND Gate)
• U2: LM78L05 (5V Regulator IC)
• R1: 2.2k 5% resistor
• R3: 330k 5% resistor
• R4: 270k 5% resistor
• R5: 1k 5% resistor
• C1: 390pF NPO capacitor
• C2, C3: 10nF
• C4: 100nF
• C5: 100uF/16V electrolytic
• C6: 220uF/16V electrolytic
• C7: 100nF ceramic
• P1: 4.7k lin. potentiometer
• L1: 22cm diameter, 14 turns, AWG 26
• K1: SPDT toggle switch
• J1: Headphone jack 1/4 or 1/8 inch

Read More

Sensor IC LM35 based Overheat Detector Alarm Switch

This is Overheat Detector Alarm Switch using Temperature Sensor IC LM35 Electronic Suite Diagram, at the heart of this overhead detector (fire alarm) circuit is a precision integrated temperature sensor type LM35 (IC1), which provides an accurately linear and directly proportional output in mV, over the zero to +155 degrees C temperature range. This can be used as part of fire smoke detectors but do not use it as a home fire alarm system.
The LM35 develops an output voltage of 10 mV/K change in measured temperature.
Designed to draw a minimal current of its own,
the LM35 has very low self heating in still air.
Here the output of the LM35 is applied to the non-inverting input of a comparator wired around a CA3130 opamp (IC2). A voltage divider network R3-P1 sets the threshold voltage, at the inverting input of the opamp. The threshold voltage determines the adjustable temperature trip level at which the circuit is activated.
When the measured temperature exceeds the user-defined level, the comparator pulls its output High to approx. 2.2 V causing transistor T1 to be forward biased instantly. T2 is also switched on, supplying the oscillator circuit around IC3 with sufficient voltage to start working. The 555 set up in astable mode directly drives active piezoelectric buzzer Bz1 to raise a loud alert. Components R7, R8 and C4 determine the on/off rhythm of the sounderA transistor based relay driver may be driven off the emitter of T1 (TP1). Similarly, replacing the piezo sounder with a suitable relay allows switching of high-power flashers, sirens or horns working on the AC mains supply.

Source: electrosuite.com

Read More

Rangkaian Detektor Kedekatan dengan Infra Merah (Infrared Proximity Detector)

Detektor kedekatan ini menggunakan detektor inframerah, dapat digunakan dalam berbagai peralatan seperti pembuka pintu otomatis dan alarm pencuri. Sirkuit yang utama terdiri dari pemancar inframerah dan penerima inframerah. Bagian pemancar terdiri dari IC pewaktu 555 dalam mode
astable. Ini adalah kabel seperti yang ditunjukkan pada gambar. Output dari astabil diumpankan ke LED inframerah melalui resistor R4, yang membatasi operasi saat ini. Sirkuit ini menyediakan output frekuensi dari 38 kHz pada 50 persen siklus, yang diperlukan untuk modul detektor / penerima inframerah. Siemens SFH5110-38 adalah pilihan yang jauh lebih baik dari SFH506-38. Siemens SFH5110-38 dihidupkan dengan frekuensi berkelanjutan dari 38 kHz dengan 50 persen siklus, sedangkan SFH506 membutuhkan frekuensi ledakan 38k untuk akal. Oleh karena itu, SFH5110-38 digunakan.

 The receiver section comprises an infrared receiver module, a 555 monostable multivibrator, and an LED indicator. Upon reception of infrared signals, 555 timer (mono) turns on and remains on as long as infrared signals are received. When the signals are interrupted, the mono goes off after a few seconds (period=1.1 R7xC6) depending upon the value of R7-C6 combination. Thus if R7=470 kilo-ohms and C6=4.7µF, the mono period will be around 2.5 seconds.

Fig. 2: Proposed arrangement for separation of IR LED and receiver module in the proximity detector

Both the transmitter and the receiver parts can be mounted on a single breadboard or PCB. The infrared receiver must be placed behind the infrared LED to avoid false indication due to infrared leakage. An object moving nearby actually reflects the infrared rays emitted by the infrared LED. The infrared receiver has sensitivity angle (lobe) of 0-60 degrees, hence when the reflected IR ray is sensed, the mono in the receiver part is triggered. The output from the mono may be used in any desired fashion. For example, it can be used to turn on a light when a person comes nearby by energising a relay. The light would automatically turn off after some time as the person moves away and the mono pulse period is over. The sensitivity of the detector depends on current-limiting resistor R4 in series with the infrared LED. Range is approximately 40 cm. For 20-ohm value of R4 the object at 25 cm can be sensed, while for 30-ohm value of R4 the sensing range reduces by 22.5 cm.

Read More

Magnetic Proximity Sensors (Sensor Magnet)

Rangkaian Sensor Magnet

 Here is an interesting circuit for a magnetic proximity switch which can be used in various applications.
The magnetic proximity switch circuit, in principle, consists of a reed switch at its heart. When a magnet is brought in the vicinity of the sensor (reed switch), it operates and controls the rest of the switching circuit. In place of the reed switch, one may, as well, use a general-purpose electromagnetic reed relay (by making use of the reed switch contacts) as the sensor, if
required. These tiny reed relays are easily available as they are widely used in telecom products. The reed switch or relay to be used with this circuit should be the ‘normally open’ type.
When a magnet is brought/placed in the vicinity of the sensor element for a moment, the contacts of the reed switch close to trigger timer IC1 wired in monostable mode. As a consequence its output at pin 3 goes high for a short duration and supplies clock to the clock input (pin 3) of IC2 (CD4013—dual
D-type flip-flop). LED D2 is used as a response indicator.
This CMOS IC2 consists of two independent flip-flops though here only one is used. Note that the flip-flop is wired in toggle mode with data input (pin 5) connected to the Q (pin 2) output. On receipt of clock pulse, the Q output changes from low to high state and due to this the relay driver transistor T1 gets forward-biased. As a result the relay RL1 is energised.

Read More

Rain Detector Alarm (Alarm Pendeteksi Air Hujan)

This circuit gives out an alarm when its sensor is wetted by water.
A 555 astable multivibrator is used here which gives a tone of about 1kHz upon detecting water.
The sensor when wetted by water completes the circuit and makes the 555 oscillate at about 1kHz.



The sensor is also shown in the circuit diagram.
It has to placed making an angle of about 30 - 45 degrees to the ground. This makes the rain water to flow through it to the ground and prevents the alarm from going on due to the stored water on the sensor.
The metal used to make the sensor has to be aluminium and not copper. This is because copper forms a blue oxide on its layer on prolonged exposure to moisture and has to be cleaned regularly.
The aluminium foils may be secured to the wooden / plastic board via epoxy adhesive or small screws.
The contact X and Y from the sensor may be obtained by small crocodile clips or you may use screws.

Read More

Gas leak detector schematic (Pendeteksi Kebocoran Gas)

Here is a gas leak detector circuit that detects the leakage of LPG gas and alerts the user through audio-visual indications. The circuit operates off a 9V PP3 battery. Zener diode ZD1 is used to convert 9V into 5V DC to drive the gas sensor module.

Gas leak detector schematic

The gas leakage circuit uses the SEN-1327 gas sensor module from RhydoLABZ. Its output goes high when the gas level reaches or exceeds certain point. A preset in the module is used to set the threshold. Interfacing with the sensor module is done through a 4-pin SIP header.
Pin details of the gas sensor module are shown in Fig. 2. An MQ-6 gas sensor is used in the gas sensor module. The sensor can also be used to detect combustible gases, especially methane.


Whenever there is LPG concentration of 1000 ppm (parts per million) in the area, the OUT pin of the sensor module goes high. This signal drives timer IC 555, which is wired as an astable multivibrator. The multivibrator basically works as a tone generator.
Output pin 3 of IC 555 is connected to LED1 and speaker-driver transistor SL100 through current-limiting resistors R5 and R4, respectively. LED1 glows and the alarm sounds to alert the user of gas leakage. The pitch of the tone can be changed by varying preset VR1. Use a suitable heat-sink for transistor SL100.

Read More

Rain Detector Circuit (Detektor Hujan)

Skema Rangkaian Detektor Hujan

Rangkaian ini sangat berguna untuk memberitahu kita bahwa hujan akan segera terjadi. Apalagi saat kita sedang menjemur pakaian. cara kerjanya cukup sederhana saat kita sedang nonton TV atau bahkan tertidur jika ada hujan turun maka secara otomatis rangkaian akan membunyikan alarm sehingga kita dapat segera memasukkan jemuran ke dalam rumah (asal kita terbangun saat mendengarnya.....).

Prinsip kerja rangkaian cukup sederhana. supaya lebih memahami prinsip kejanya coba lihat gambar rangkaian berikut.





angkaian ini akan menggunakan IC555 yaitu ic timer. pada aplikasi ini kita gunakan sebagai pembangkit sinyal kotak dengan frekuensi 1 KHz. Pada titik A-B kita hubungkan ke sensor air yang kita buat sendiri. Jika titik AB terhubung maka IC 555 akan mengahasilkan sinyal kotak pada kaki no 3 sehingga speaker akan berbunyi.

Untuk membuat sensor air sebenarnya terserah ukurannya yang jelas semakin lebar/besar semakin bagus karena kemungkinan tetes air hujan menganai papan semakin besar. dan jangan lupa meletakkan sensor air di luar rumah suapaya saat terkena air hujan sensor mejadi aktif. untuk aluminium foil kita bisa menggunakan bekas pembungkus makanan ringan.

Read More