📡 9M2PJU APRS Passcode Generator

⚡ A fast, friendly web tool to generate APRS-IS passcodes from amateur radio callsigns.
Live at 🌍 pass.hamradio.my

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🌟 Features

• ⚡ Instant APRS passcode generation
• 📱 Responsive layout for mobile & desktop
• 🧠 Real-time validation with visual feedback
• 🔵 Callsigns styled in blue, UPPERCASE
• 🔴 Passcodes shown in bold red
• 📲 Android app included

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🚀 Get Started

🔗 Visit: https://pass.hamradio.my

1. Type your valid callsign
2. Click Generate
3. View your APRS passcode instantly

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🧩 Embed in Your Website

<iframe 
  src="https://pass.hamradio.my" 
  style="width: 100%; height: 500px; border: none;" 
  allowfullscreen
></iframe>

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📡 What is APRS?

APRS (Automatic Packet Reporting System) is a digital radio protocol used in amateur radio for:

• 🔍 Position tracking
• 🌦️ Weather telemetry
• 💬 Messaging & bulletins
• 🔁 Repeater beacons & more

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🔐 How Passcodes Work

APRS-IS requires a numeric passcode for authentication.
This tool uses the standard algorithm:

1. Strip SSID (-1, -7, etc.)
2. Convert callsign to uppercase
3. Bitwise operations per character:
   • XOR with constants
   • Bit shifts
   • Merge with 0x73
4. Return 16-bit APRS passcode

Example:

• Input: 9W2XYZ-9
• Processed: 9W2XYZ
• Output: passcode = 56789 (example)

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🛠️ Developer Guide

🧰 Requirements

• HTML, CSS, JavaScript (ES6+)
• Basic Git knowledge

🔧 Setup

git clone https://github.com/9M2PJU/9M2PJU-APRS-Passcode-Generator.git
cd 9M2PJU-APRS-Passcode-Generator
open index.html

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🤝 Contribute

All contributions welcome!

# Step 1: Fork
git checkout -b feature/NewFeature

# Step 2: Commit changes
git commit -m "Add: NewFeature"

# Step 3: Push to GitHub
git push origin feature/NewFeature

# Step 4: Open a Pull Request

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📲 Android App

📥 Download APK

• Offline use supported
• Fast & lightweight

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📄 License

Released under the GNU GPL v3

Free to use, improve, and redistribute with attribution.

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🙏 Credits

• Built with ❤️ by 9M2PJU
• Thanks to @JollyJolli for early support

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🌐 Empowering the Amateur Radio Community — One Call at a Time