RFID Card Reader – 125 kHz JT308 (USB Proximity Reader) — simple plug‑and‑play RFID reader for low‑frequency cards (EM4100 compatible).

📌 Overview

The JT308 RFID Card Reader is a 125 kHz USB‑connected proximity card reader designed to read LF RFID cards (e.g., EM4100 / EM4200 type). It’s widely used for:

• Access control systems

• Attendance tracking

• ID verification

• PC applications that take input like a keyboard (e.g., Excel, Word)

🔍 Key Specifications

📡 Frequency: 125 kHz (LF RFID) — supports EM4100/compatible tags/cards.
🔌 Interface: USB (plug‑and‑play, no drivers required on most systems). 
🔢 Card Data Output: Sends the card ID directly as keyboard input (typically the first 10 digits). 
📏 Reading Distance: Around 5–8 cm depending on environment & card type.
🖥️ Compatibility: Works with Windows platforms and any software that accepts keyboard input. 
🚦 Indicators: Built‑in LED & buzzer for read‑confirmation.
📦 Power: Powered via USB (5 V). 
📐 Size & Weight: Compact (~95 × 61 × 10 mm, ~33 g).

📌 How It Works

1. Plug the reader into a USB port — system recognizes it automatically (no driver).

2. Hold a 125 kHz RFID card / tag near the reader — card serial number is read.

3. The reader outputs the ID number directly into whatever app has focus (like a keyboard).

This makes integration with existing software very easy, since you don’t need special SDKs — just treat it as keyboard input.

📦 Typical Uses

✅ Attendance & time tracking
✅ Simple access authentication
✅ Database entry interfaces
✅ DIY projects (Arduino/PC based)
✅ PC login systems that use card number in