Saturday, October 25, 2025

How to Repair Philips LED Batten 18W Not Working (Step-by-Step Guide)

Have you ever turned on your LED batten light and realized — nothing happens? No glow, no flicker, just dead? Don’t rush to throw it away yet! In this guide, we’ll show you how to troubleshoot and repair a Philips LED Batten 18W Linear Light that’s not working.

Comparison between working and faulty Philips LED Batten 18W.

πŸ”§ What You Need

  • Multimeter (for voltage and diode testing)
  • Soldering iron and flux
  • Replacement MB10F bridge rectifier (if faulty)
  • Screwdriver or pry tool
  • Basic safety gear (gloves and insulated tools)

πŸ’‘ Step 1: Check Power Input

Start by turning on the switch and using a multimeter to measure the input voltage.

Measuring AC input voltage with a multimeter.

If the voltage (around 220V AC) is present, that means the power supply is fine, and the issue lies inside the LED batten.


πŸ”© Step 2: Disassemble the LED Batten

Remove the end cover — look for a small clip or hole at the edge. Push down gently and pry open the cover using a small screwdriver.

Removing the end cover to access the LED strip and driver.

Once opened, slide out the LED strip to expose the internal wiring and driver.

Sliding out the LED strip to reveal the internal wiring and driver circuit inside the batten.

πŸ” Step 3: Inspect the Wiring

When inspecting the LED strip, check for loose wires or bad solder joints.

Loose red wire disconnected from the LED strip solder joint.

In our case, the red wire was detached from its solder point — one clear reason for no light output.


⚡ Step 4: Measure DC Output Voltage

Use your multimeter to measure the driver’s DC output voltage. You should see around 24V–40V DC for an 18W batten.

Checking the DC output voltage of the LED driver circuit.

If you’re only getting 4V DC, it means the driver circuit or the bridge rectifier (MB10F) is likely damaged.


🧲 Step 5: Test the MB10F Bridge Rectifier

Refer to the MB10F pin diagram and switch your multimeter to diode mode. Measure these pairs:

  • Pin 3 → Pin 4
  • Pin 3 → Pin 2
  • Pin 2 → Pin 1
  • Pin 4 → Pin 1
Testing MB10F bridge rectifier using diode mode on a multimeter.

If there’s no reading between all pairs, it confirms the rectifier is open and faulty.


πŸ”§ Step 6: Identify Root Cause

We found two issues in this repair:

  1. Loose solder joint on the LED output wire.
  2. Faulty MB10F bridge rectifier (no diode connection).

These two faults combined caused the LED batten to completely fail.


πŸ”₯ Step 7: Replace the Faulty MB10F

Desolder the damaged MB10F using a soldering iron or hot air gun. Apply some flux to make removal easier.

Removing the faulty MB10F bridge rectifier.

Removing and replacing the faulty MB10F bridge rectifier.

Then, solder a new MB10F IC in its place — ensure the polarity and pin orientation are correct.


⚙️ Step 8: Test and Reassemble

After replacing the component, connect the LED batten to the AC supply and test. If the repair was successful, your LED should now light up brightly again!

Testing the LED batten after repair — light working normally.

Finally, reassemble the cover and secure everything back in place.


✅ Result: Fully Working LED Batten

After fixing both issues, the Philips LED Batten 18W worked perfectly. A simple inspection and a few minutes of soldering saved it from going to waste — and saved money too!

Final result — repaired Philips LED Batten shining brightly.

πŸ“¦ Where to Buy

Shopee:
Lazada:
Aliexpress:

πŸ“Ί Watch the Full Video

You can watch the complete step-by-step repair process here:


πŸ’¬ Final Thoughts

Most LED battens fail due to loose solder joints or driver circuit damage — both easy to diagnose with a simple multimeter. With a bit of patience and care, you can repair your light instead of replacing it.

If you found this guide helpful, don’t forget to subscribe, like, and share the video for more electronics repair tutorials. πŸ’‘πŸ”§

Monday, October 20, 2025

How to Make a Bluetooth Controlled 2WD Smart Car Using Arduino

 Have you ever wanted to build your own robot car that you can control straight from your smartphone? πŸš—πŸ’‘In this tutorial, we’ll show you how to make a Bluetooth-controlled 2WD smart robot car using Arduino UNO, an HC-05 Bluetooth module, and an L298N motor driver. You’ll be able to move it forward, backward, left, right — and stop — all from your phone using the UBRcontrol app.

Bluetooth Controlled 2WD Smart Car using Arduino UNO.


⚙️ What is a 2WD Smart Car?

A 2WD (two-wheel drive) smart car is a small robotic platform powered by two DC motors and a caster wheel for balance. It’s widely used in Arduino robotics projects for learning motor control, Bluetooth communication, and basic automation.


🧩 Components Required

To build this project, you’ll need the following components:
All the essential parts you need to build your Bluetooth-controlled 2WD smart car using Arduino.
  1. Arduino UNO × 1
  2. HC-05 Bluetooth Module × 1
  3. L298N Motor Driver × 1
  4. 2WD Smart Robot Car Chassis Kit × 1
  5. Breadboard & Jumper Wires × 1
  6. Batteries × 4/6


πŸ”§ Assembling the Car Chassis

Step 1: Mount the DC Motors

Attach the two DC motors to the chassis sides using the provided metal brackets and screws. Ensure both shafts face outward.

Attach both DC motors to the chassis using metal brackets and screws.

Step 2: Install the Wheels & Caster

Fix the wheels onto the motor shafts.

Attach the front caster wheel for support.

Press the yellow wheels onto each motor shaft and fix the caster wheel at the front for support.

Step 3: Mount the Battery Holder

Secure the 4 or 6×AA battery holder on the top plate of the chassis.

Fix the 6×AA battery holder at the top center of the chassis using screws or double-sided tape.

Step 4: (Optional) Power Switch

Install a small ON/OFF switch between the battery and motor driver if desired.

You can install a small ON/OFF switch between the battery positive wire and the motor driver — but in this project, we connected the battery directly.


🧠 Installing the Electronics

Step 1: Mount the Modules

Place the Arduino UNO, L298N motor driver, and a small breadboard on the chassis top plate.

Place the Arduino UNO, L298N Motor Driver, and a small breadboard on the top plate of the chassis.


Step 2: Connect Motors to L298N

Wire the left and right DC motors to the L298N motor driver outputs (OUT1–OUT4).

  • Left motor → OUT1, OUT2

  • Right motor → OUT3, OUT4


Step 3: Power Connections

Connect the battery holder directly to the L298N power terminals (12V and GND) and share ground with the Arduino.
  • Battery + → 12V on L298N

  • Battery – → GND on L298N

  • L298N GND → Arduino GND (common ground)


Step 4: L298N to Arduino

Link the control pins IN1–IN4 from the L298N to Arduino pins 9, 8, 7, and 6.
  • IN1 → Pin 9

  • IN2 → Pin 8

  • IN3 → Pin 7

  • IN4 → Pin 6

  • ENA, ENB → 5V (full speed)


Step 5: Connect HC-05 Bluetooth Module

Use a small breadboard to mount the HC-05 and resistors, then connect it to Arduino pins 2 and 3.

Use a small breadboard to attach the HC-05 and resistors:

  • VCC → 5V

  • GND → GND

  • TX → Pin 2

  • RX → Pin 3 (through 1 kΞ© & 2 kΞ© voltage divider)


πŸ’» Arduino Code

You can download the code HERE.

#include <softwareserial.h>
SoftwareSerial BT(2,3); // RX=2, TX=3

// Motor pins (L298N)
const int ENA=10, IN1=9, IN2=8;    // Right motor
const int ENB=11, IN3=7, IN4=6;    // Left motor
int motorSpeed=200;

byte buf[10]; // buffer for incoming bytes
int bufIndex=0;

void setup(){
  Serial.begin(9600);
  BT.begin(38400);
  Serial.println("πŸ”Ή 2WD Car Ready - Waiting for commands");

  pinMode(ENA, OUTPUT); pinMode(ENB, OUTPUT);
  pinMode(IN1, OUTPUT); pinMode(IN2, OUTPUT);
  pinMode(IN3, OUTPUT); pinMode(IN4, OUTPUT);

  stopCar();
}

void loop(){
  while(BT.available()){
    byte b = BT.read();
    buf[bufIndex++] = b;
    if(bufIndex > 9) bufIndex = 0; // prevent overflow

    // -------- Left Control --------
    if(bufIndex >= 3){
      // Upward - Forward
      if(buf[bufIndex-3]==248 && buf[bufIndex-2]==0 && buf[bufIndex-1]==248){
        Serial.println("↑ Left Up - Forward");
        forward(500); bufIndex=0;
      }
      // Downward - Backward
      else if(buf[bufIndex-3]==0 && buf[bufIndex-2]==128 && buf[bufIndex-1]==248){
        Serial.println("↓ Left Down - Backward");
        backward(500); bufIndex=0;
      }
      // Left - Turn Left
      else if(buf[bufIndex-3]==120 && buf[bufIndex-2]==248 && buf[bufIndex-1]==120){
        Serial.println("← Left - Turn Left");
        left(500); bufIndex=0;
      }
      // Right - Turn Right
      else if(buf[bufIndex-3]==128 && buf[bufIndex-2]==0 && buf[bufIndex-1]==248){
        Serial.println("→ Left - Turn Right");
        right(500); bufIndex=0;
      }
      // Center - Stop
      else if(buf[bufIndex-3]==128 && buf[bufIndex-2]==128 && buf[bufIndex-1]==248){
        Serial.println("■ Left Center - Stop");
        stopCar(); bufIndex=0;
      }
    }

    // -------- Right Control --------
    if(bufIndex >= 3){
      // Upward - Forward
      if(buf[bufIndex-3]==248 && buf[bufIndex-2]==128 && buf[bufIndex-1]==248){
        Serial.println("↑ Right Up - Forward");
        forward(500); bufIndex=0;
      }
      // Downward - Backward
      else if(buf[bufIndex-3]==0 && buf[bufIndex-2]==248 && buf[bufIndex-1]==248){
        Serial.println("↓ Right Down - Backward");
        backward(500); bufIndex=0;
      }
      // Left - Turn Left
      else if(buf[bufIndex-3]==120 && buf[bufIndex-2]==128 && buf[bufIndex-1]==248){
        Serial.println("← Right Left - Turn Left");
        left(500); bufIndex=0;
      }
      // Right - Turn Right
      else if(buf[bufIndex-3]==128 && buf[bufIndex-2]==128 && buf[bufIndex-1]==248){
        Serial.println("→ Right Right - Turn Right");
        right(500); bufIndex=0;
      }
      // Center - Stop
      else if(buf[bufIndex-3]==0 && buf[bufIndex-2]==248 && buf[bufIndex-1]==248){
        Serial.println("■ Right Center - Stop");
        stopCar(); bufIndex=0;
      }
    }
  }
}

/* ----- Motor functions with duration ----- */
void forward(int duration){
  digitalWrite(IN1,HIGH); digitalWrite(IN2,LOW);
  digitalWrite(IN3,HIGH); digitalWrite(IN4,LOW);
  analogWrite(ENA,motorSpeed); analogWrite(ENB,motorSpeed);
  delay(duration);
  stopCar();
}

void backward(int duration){
  digitalWrite(IN1,LOW); digitalWrite(IN2,HIGH);
  digitalWrite(IN3,LOW); digitalWrite(IN4,HIGH);
  analogWrite(ENA,motorSpeed); analogWrite(ENB,motorSpeed);
  delay(duration);
  stopCar();
}

void left(int duration){
  digitalWrite(IN1,LOW); digitalWrite(IN2,HIGH);
  digitalWrite(IN3,HIGH); digitalWrite(IN4,LOW);
  analogWrite(ENA,motorSpeed); analogWrite(ENB,motorSpeed);
  delay(duration);
  stopCar();
}

void right(int duration){
  digitalWrite(IN1,HIGH); digitalWrite(IN2,LOW);
  digitalWrite(IN3,LOW); digitalWrite(IN4,HIGH);
  analogWrite(ENA,motorSpeed); analogWrite(ENB,motorSpeed);
  delay(duration);
  stopCar();
}

void stopCar(){
  digitalWrite(IN1,LOW); digitalWrite(IN2,LOW);
  digitalWrite(IN3,LOW); digitalWrite(IN4,LOW);
  analogWrite(ENA,0); analogWrite(ENB,0);
}

πŸ“± Pairing and App Setup (UBRcontrol App)

  1. Turn on the car and open UBRcontrol on your phone.

    Insert the batteries and turn on your smart car the HC-05 Bluetooth module’s LED should start blinking.

    Launch the UBRcontrol app on your smartphone to begin pairing.

  2. Pair with HC-05.

    Connect to the HC-05 Bluetooth module.

  3. Go to Settings → Control Settings → Left Controls.

  4. Assign buttons:

    • c: Forward

    • d: Backward

    • a: Left

    • b: Right

    • r: Stop


πŸš— Final Test

Insert the batteries and power up your car. Once the Bluetooth module lights up, connect via UBRcontrol.

  • Press Forward (c) → Car moves forward

  • Press Backward (d) → Moves backward

  • Press Left (a) / Right (b) → Turns direction

  • Press Center (r) → Stops the car


Your Bluetooth-controlled Arduino robot car is ready — have fun driving it!

Enjoy your fully functional Bluetooth-controlled 2WD robot car!


πŸ“¦ Where to Buy

Shopee:
Lazada:
Aliexpress:


πŸ“Έ Conclusion


You’ve just built your own Arduino Bluetooth Smart Car! This project teaches basic motor control, serial communication, and smartphone interfacing — a great foundation for future robotics projects like line following or obstacle avoidance.

πŸ’¬ Don’t forget to Like, Share, and Subscribe for more Arduino and DIY electronics projects! πŸš—πŸ’‘

Wednesday, October 15, 2025

NETUM E800 2D Wireless Barcode Scanner Review – Bluetooth Setup & Test

If you’re looking for a reliable barcode scanner that supports both 1D and 2D barcodes, the NETUM E800 might be the perfect choice. In this review, we’ll unbox the E800, explore its features, show how to connect it via Bluetooth, and test its performance on different barcodes.

NETUM E800 2D Wireless Barcode Scanner – Smart, portable, and powerful.

πŸ“¦ What’s in the Box

When you open the NETUM E800 package, you’ll find:

  • 1× E800 Wireless Barcode Scanner

  • 1× USB Cable

  • 1× 2.4GHz USB Dongle

  • 1× Retractable Clip

  • 1× Clip

  • 1× Quick Setup Guide

All items included with the NETUM E800 scanner package.

Everything you need to get started right away — whether for retail, warehouse, or office applications.


🧠 Design Overview

The E800 features a compact and ergonomic design, built for comfort during long hours of use. It’s lightweight but feels solid in hand, with a matte finish that provides a good grip. Perfect for scanning barcodes at counters, stockrooms, or even on the go.

Ergonomic and durable design of the NETUM E800 barcode scanner.

πŸ”§ Connectivity Options

One of the main highlights of the NETUM E800 is its triple connection support.
You can use it in three different modes:

  1. Bluetooth Mode – Connect wirelessly to smartphones, tablets, or laptops.

  2. 2.4GHz Wireless Mode – Use the included USB dongle for plug-and-play wireless connection.

  3. USB Wired Mode – Connect directly using the USB cable for a stable, no-lag setup.


πŸ“± How to Connect via Bluetooth

Connecting the NETUM E800 via Bluetooth is quick and simple:

  1. Turn on the scanner by pressing the power button.

    Press and hold the power button to turn on the NETUM E800 scanner.
  2. Scan the “Bluetooth Transmit” barcode from the quick setup guide — the scanner will power off automatically.

    Scan the ‘Bluetooth Transmit’ barcode from the quick setup guide to enable Bluetooth mode.
  3. Press the power button again. The blue LED will start flashing, indicating pairing mode.

    Press the power button again — the blue LED starts flashing, indicating Bluetooth pairing mode
  4. On your device, open Bluetooth settings and select “E Barcode Scanner” to pair.

    On your phone or laptop, open Bluetooth settings and select ‘E Barcode Scanner’ to pair.
  5. Once connected, open any app (like Notes) and scan a barcode — the data will appear instantly.

    Open your Notes app and scan a barcode — the data appears instantly on screen.

This makes it perfect for use with mobile devices or tablets in a wireless environment.


πŸ”— Lanyard and Clip Installation

The E800 comes with both a retractable clip and a lanyard, making it easier to carry around.

To attach the lanyard:

Insert the lanyard into the slot at the retractable clip for easy carrying.

Insert the lanyard into the slot at the retractable clip and clip it securely. It’s ideal for hands-free use while working in warehouses or on delivery routes.

To attach the clip to your phone:

Tear off the adhesive sticker on the back of the clip and attach it to your phone or case.

Tear off the adhesive sticker on the back of the clip and stick it to your phone or case. 

The clip keeps the scanner accessible for quick, hands-free barcode scanning.

This setup keeps the scanner accessible during mobile scanning tasks.


✅ Final Thoughts

The NETUM E800 2D Wireless Barcode Scanner is an excellent tool for anyone needing a fast, flexible, and portable barcode scanning solution. With its Bluetooth, 2.4GHz, and USB connectivity options plus strong performance on all barcode types it’s ideal for retail counters, inventory management, or warehouse tracking. Whether you’re running a small shop or managing logistics, the E800 offers great value for money.


πŸ“¦ Where to Buy

Shopee:
Lazada:
Aliexpress:


πŸ“Ή Watch the Full Review Video

πŸŽ₯ Watch the full video review to see unboxing, Bluetooth setup, and performance test in action. πŸ‘‰ Don’t forget to like, share, and subscribe for more tech reviews!

Friday, October 10, 2025

How a 4x3 Membrane Keypad Works | Continuity Test & Internal Circuit Explained

In this post, we’ll take a closer look at how a 4x3 membrane keypad works — the same type used in calculators, security panels, and Arduino projects. You’ll learn how the keypad detects key presses, how the membrane layer creates continuity, and how each button connects to the circuit to send signals to a microcontroller.

A 4x3 membrane keypad used in Arduino and electronic input projects.

🧩 What is a 4x3 Membrane Keypad?

A 4x3 keypad has 12 buttons arranged in 4 rows and 3 columns, similar to a phone keypad (1–9, *, 0, #). 

The 4x3 matrix keypad layout — each button connects one row and one column.

It’s called a membrane keypad because the button layer is made from thin, flexible plastic sheets with conductive surfaces that close the circuit when pressed. Each button connects one row line and one column line — that’s how the system identifies which key is pressed.


⚙️ Internal Layers of the Keypad

Once opened, you can clearly see it’s made up of three layers:

  1. Button layer – where you press the keys.

  2. Membrane sheet – contains conductive black carbon pads.

  3. Circuit board (PCB) – has the printed traces connected to the pins.

Inside the keypad: buttons, membrane layer with carbon pads, and the PCB.

These layers work together to make or break the circuit when a button is pressed.


πŸ” Continuity Test with a Multimeter

To test the membrane layer:
  1. Set your multimeter to continuity mode.

  2. Place the probes on both sides of a black circular pad on the membrane.

  3. When pressed, the meter shows continuity or low resistance, which means current can flow through.

Testing the membrane pad with a multimeter in continuity mode.

✅ This confirms that each pad acts as a switch — it closes the circuit only whcen pressed.


🧠 How the Circuit Works

On the PCB, you can see multiple circuit traces running across the board. Each key position is an open circuit by default, meaning no current flows. When a key is pressed, the membrane pad bridges the two traces, closing the circuit.
Each trace leads to a pin — the circuit closes only when the key is pressed.

On the left side of the PCB, the pins are labeled from pin 0 to pin 9 — each connected to a row or column. When the circuit is closed, the microcontroller detects which row and column were connected, identifying the exact key pressed.


πŸ§ͺ Testing the Keypad

After assembling the keypad back together:

  1. Connect it according to the 4x3 wiring layout.

  2. Test by pressing key “2” — you should see continuity between pin 2 and pin 3.

  3. Try other keys and compare results — each button connects a unique pair of pins.

Pressing key “2” connects pin 2 and pin 3, confirming a closed circuit.

This is how the microcontroller can detect multiple buttons using only 7 I/O pins.


πŸ“Ή Video Summary


In the video version of this tutorial:

  • We disassembled the keypad

  • Tested the membrane using a multimeter

  • Explained open and closed circuits

  • Checked pin layout and microcontroller detection

  • Reassembled and tested real button presses

It’s a simple yet fascinating way to understand how everyday input devices work!


πŸ“¦ Where to Buy

Shopee:
Lazada:
Aliexpress:


🎬 Conclusion

A membrane keypad works by completing a circuit through thin flexible layers. Each keypress connects specific row and column traces, allowing the microcontroller to recognize which button was pressed. With just a multimeter and a bit of curiosity, you can easily test and understand the working principle of this common input device.

πŸ’‘ Don’t forget to Like, Subscribe, and Share if you enjoyed learning how a 4x3 keypad works!

Saturday, October 4, 2025

DIY STEM Oscillating Head Fan | Build Your Own Working Fan with Switch & Moving Head

This DIY STEM Oscillating Head Fan is a fun hands-on project designed to teach students and makers about mechanical movement, electric motors, and circuit assembly. By assembling this fan, you’ll learn how electricity powers a motor and how gears convert rotation into side-to-side oscillation — just like a real electric fan!

STEM Fan Kit – motor, fan blade, and plates ready to assemble.

Perfect for classrooms, STEM activities, or home experiments, this project combines creativity with basic engineering and electrical concepts.


πŸͺ΅ Step-by-Step Assembly Guide

Step 1: Unbox the Kit

Open your DIY Science Kit and check that all 19 wooden plates, screws, motor, and wires are included.

All components included in the DIY STEM Fan Kit.

Step 2: Build the Base

Assemble plates 1 and 2, then attach plate 3 on top to create the main platform.

Assemble plates 1 and 2.

Attach plate 3 on top.


Add plates 4 and 5 underneath as support brackets using screws.

Insert plate 6, ensuring it faces the correct direction.

Step 3: Prepare the Motor

Attach two long phase wires to the motor terminals as shown in the diagram.

Connecting phase wires to the motor

Assemble plates 7 and 8 to form the motor holder, then mount the motor using plate 9 and screws.

Assemble plates 7 and 8. 

Mounting the motor inside the holder.

Step 4: Strengthen the Frame

Add plates 10 and 11 to the motor section and secure with screws.

Reinforcing the motor frame.

Attach plate 12 on top to lock the motor in place.

Locking the motor securely with plate 12.

Insert plates 13 and 14 onto the motor shaft and fix them firmly.

Mounting plates 13 and 14 onto motor shaft

Step 5: Combine and Connect

Insert three plate No. 15 onto plates 7 and 10 as shown.

Adding plates 15 to strengthen the structure.

Place the motor assembly onto plates 4 and 5, guiding the wires through the small hole.

Aligning motor assembly with base support.

Use plates 16 and 20 to connect plate 6 and plate 13, then secure with screws and the orange spacer.

Connecting components using spacers and screws.

Step 6: Wiring and Switch Installation

Install the battery box and switch, making sure the wires are facing the correct direction.
Tighten with screws to secure.

Battery box and switch connection,

Step 7: Add Final Parts

Attach plate 17 and fix the fan blade onto the motor shaft.

Installing the fan blade on the motor.

Fix the fan blade.

Finally, add plates 18 and 19 to complete the fan housing.

Final assembly with plates 18 and 19.

Check all parts.

πŸ”‹ Testing the Fan

Insert the batteries, turn on the switch, and watch your fan spin and oscillate! You’ve now built a working STEM oscillating fan that demonstrates real-world mechanical movement and electrical control.

Testing and watching the oscillating motion

πŸŽ“ Learning Outcome

This project helps students understand:
✅ How DC motors convert electrical energy into motion
✅ The mechanism of oscillation in fans
✅ The role of switches and wiring in controlling circuits


πŸ“¦ Where to Buy

Shopee:
Lazada:
Aliexpress:

πŸŽ₯ Watch the Full Tutorial

Want to see it in action? Watch our DIY STEM Oscillating Head Fan video tutorial on YouTube!


❤️ Closing

Thanks for following along! If you enjoyed this project, please Like πŸ‘, Share πŸ”, and Subscribe πŸ”” to our channel for more DIY STEM tutorials.