Hardware Overview

A TARPN node consists of several key components working together to provide packet radio connectivity.

Architecture

┌─────────────────────────────────────────────────────────┐
│                    TARPN Node                           │
├─────────────────────────────────────────────────────────┤
│                                                         │
│  ┌──────────┐    ┌──────────┐    ┌──────────────────┐  │
│  │ Antenna  │◄──►│  Radio   │◄──►│    NinoTNC       │  │
│  │  (VHF)   │    │   #1     │    │      #1          │  │
│  └──────────┘    └──────────┘    └────────┬─────────┘  │
│                                           │ USB        │
│  ┌──────────┐    ┌──────────┐    ┌───────▼──────────┐  │
│  │ Antenna  │◄──►│  Radio   │◄──►│    NinoTNC       │  │
│  │  (UHF)   │    │   #2     │    │      #2          │  │
│  └──────────┘    └──────────┘    └────────┬─────────┘  │
│                                           │ USB        │
│  ┌────────────────────────────────────────▼─────────┐  │
│  │              Raspberry Pi                         │  │
│  │  ┌─────────────────────────────────────────────┐ │  │
│  │  │           LinBPQ (G8BPQ Node)               │ │  │
│  │  │  • Packet Routing     • Web Interface       │ │  │
│  │  │  • BBS Mail System    • Chat Server         │ │  │
│  │  └─────────────────────────────────────────────┘ │  │
│  └──────────────────────────────────────────────────┘  │
│                                                         │
│  ┌──────────────────────────────────────────────────┐  │
│  │              13.8V Power Supply                   │  │
│  └──────────────────────────────────────────────────┘  │
└─────────────────────────────────────────────────────────┘

Components

Raspberry Pi

The brain of the node. Runs LinBPQ software for packet switching.

• Recommended: Raspberry Pi 4B (1GB+ RAM)
• Also supported: Pi 3B, 3B+, Zero 2W
• OS: Raspberry Pi OS (Bullseye or Bookworm)

NinoTNC

Terminal Node Controller - converts digital data to/from radio signals.

• Model: N9600A (current version)
• Interface: USB (appears as /dev/ttyUSB*)
• Protocols: AX.25, IL2P (with FEC)
• Speeds: 300 - 19200 baud

Radios

VHF/UHF FM transceivers for the RF links.

• Recommended: Surplus commercial land-mobile radios
• Power: 25-50W typical
• Bands: 2m (144 MHz), 70cm (440 MHz), 6m (50 MHz)

Power Supply

• Main: 13.8V DC supply for radios (20A+ recommended)
• Pi: USB-C 5.1V 3A (can use 12V-5V converter)
• Backup: Optional GelCel battery for Pi

Enclosure

Houses all components in a single portable unit.

• 3D Printed: STL files provided
• Wooden: Traditional cabinet build
• Commercial: Various rack-mount options

Typical Configurations

Single Port (Starter)

• 1x Raspberry Pi
• 1x NinoTNC
• 1x Radio
• 1x Antenna

Cost: ~$200-300

Dual Port (Standard)

• 1x Raspberry Pi
• 2x NinoTNC
• 2x Radio
• 2x Antenna

Cost: ~$500-650

Multi-Port (Advanced)

• 1x Raspberry Pi
• 3-4x NinoTNC
• 3-4x Radio
• Multiple antennas

Cost: ~$800+

Next Steps

1. Shopping List - Complete parts list with links
2. Raspberry Pi Setup - Choosing and preparing the Pi
3. NinoTNC - TNC assembly and configuration
4. Radios - Radio selection and wiring