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.

📦 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.

🔧 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.

📱 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.

🔗 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.

📦 Where to Buy

Shopee:

1. NETUM E800

Lazada:

1. NETUM E800

TikTok:

1. NETUM E800

Aliexpress:

1. NETUM E800

📹 Watch the Full Review Video

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

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.

🔍 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.

🧪 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.

📹 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!

📦 Where to Buy

Shopee:

1. Oscillating Head Fan

Lazada:

1. Oscillating Head Fan

TikTok:

1. Oscillating Head Fan

Aliexpress:

1. Oscillating Head Fan

🎬 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.

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

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.

🪵 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.

🔋 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

🎓 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

📦 Where to Buy

Shopee:

1. Oscillating Head Fan

Lazada:

1. Oscillating Head Fan

TikTok:

1. Oscillating Head Fan

Aliexpress:

1. Oscillating Head Fan

🎥 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 👍, Share 🔁, and Subscribe 🔔 to our channel for more DIY STEM tutorials.

How to Build a STEM DIY Twin Aircraft | Step-by-Step Guide

✨ Introduction

Ever wondered how airplanes work and wanted to build your own model? In this guide, we’ll show you how to make a twin-propeller aircraft from scratch. This project is simple, fun, and educational — a great way to learn about aerodynamics, thrust, and lift. By the end, you’ll have your very own working aircraft model!

🔧 What is a Twin Propeller Aircraft?

A twin-propeller aircraft is a small model plane powered by two electric motors with propellers. The motors generate thrust, while the wings provide lift. This setup mimics the structure of real airplanes and helps demonstrate how aircraft fly.

🛠️ Step-by-Step Assembly

1. Unboxing and Preparation

Open your kit and check that all parts are included. Lay them out neatly so you can easily follow the steps.

🔎 All parts ready — motors, propellers, wires, battery box, wings, wheels, and wooden fuselage.

2. Install the Battery Box

Connect the red wires to the left side of the battery box and the black wires to the right side. This will power your motors later.

🔋 Battery box connected with red and black wires for power.

3. Install the Motors

Attach the red wires to the left terminals of the motors and the black wires to the right terminals. Secure both motors between the two wing pieces using double-sided tape. Finally, attach the propellers to the motor shafts.

⚙️ Motors wired

4. Install the Wing Assembly

Now place the completed motor-and-propeller assembly inside the wings. Make sure everything is firmly attached.

Secured the motor between the wings with double-sided tape.

5. Assemble the Aircraft Body

Prepare the long wooden fuselage. Use double-sided tape to attach the hole block, non-hole block, curved block, and slanted block. This forms the structure of your aircraft.

📏 Wooden fuselage with blocks (hole, non-hole, curved, slanted) attached in place.

6. Install the Wheels

Insert the two metal axles through the blocks at the bottom of the fuselage. Attach the wheels to the ends of the axles. These provide balance and allow smooth movement forward.

🚗 Axles inserted through blocks, wheels added for stability and smooth movement.

7. Mount Wing and Battery Box

Carefully attach the wing-motor assembly on top of the fuselage. Then, secure the battery box to the fuselage using double-sided tape.

🔧 Wing assembly and battery box secured on top of fuselage.

8. Final Test

Switch on the battery box and watch the propellers spin! Place your aircraft on a smooth surface and let it glide forward under its own thrust.

✅ Propellers spinning, aircraft ready to glide forward!

📦 Where to Buy

Shopee:

1. Twin Aircraft

Lazada:

1. Twin Aircraft

TikTok:

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Aliexpress:

1. Twin Aircraft

✅ Conclusion

You’ve now built your very own twin-propeller aircraft! 🎉 This DIY project is not only fun but also a great way to understand the science of flight.

👉 Try experimenting with propeller size, wing angle, or motor speed to see how performance changes.

And if you enjoyed this project, don’t forget to Like, Share, and Subscribe to our YouTube channel for more step-by-step tutorials!

TTRacing Duo V4 Unboxing & Assembly Guide | Full Setup & Function Test

The TTRacing Duo V4 is one of the most popular entry-level gaming chairs, offering comfort, adjustability, and stylish design for gamers and office users alike. If you’ve just received your chair, congratulations! In this blog, we’ll guide you through the unboxing, assembly, and testing process so you can set it up quickly and enjoy hours of comfort.

TTRacing Duo V4 gaming chair.

What’s in the Box?

When you open the package, you’ll find all the essential parts neatly arranged:

• Seat base

• Backrest

• Armrests (left & right)

• Wheelbase with 5 caster wheels

• Gas lift & protective cover

• Control mechanism (tilt & height adjustment)

• Screws and Allen key (tools included)

Assembly Steps

Step 1 – Attach the Wheels

Insert all five caster wheels firmly into the wheelbase until you hear a click.

Step 2 – Install the Gas Lift

Place the gas lift into the center of the wheelbase and cover it with the protective sleeve.

Step 3 – Assemble the Seat Base

Flip the seat base upside down, align the control mechanism, and secure it with screws using the Allen key.

Step 4 – Attach the Armrests

Position the armrests on both sides of the seat base and fasten them securely with screws.

Step 5 – Connect the Backrest

Align the backrest with the seat base, then secure both sides with screws.

Step 6 – Mount the Seat

Carefully place the seat onto the gas lift. Ensure it sits firmly in place.

Function Testing

Once assembled, it’s time to test the chair’s features to make sure everything works smoothly.

1. Back Pressure Adjustment
   
   

   

   Rotate the knob under the seat to tighten or loosen the back pressure.

   
   

2. Chair Rotation
   
   

   

   Sit on the chair and check for smooth 360° rotation.

   
   

3. Height Adjustment
   

   

   Use the lever to raise or lower the seat to your preferred height.

   
   

4. Tilt Mechanism
   

   

   Pull the lever outward to unlock the tilt, and push it back in to lock.
   
   

📦 Where to Buy

Shopee:

1. TTRacing Duo V4

Lazada:

1. TTRacing Duo V4

TikTok:

1. TTRacing Duo V4

Final Thoughts

The TTRacing Duo V4 is simple to set up and offers excellent comfort for long gaming or working sessions. Its adjustable features allow you to customize your seating experience easily. Whether you’re gaming, studying, or working from home, this chair is a solid choice.