mcnanovna Overview

mcnanovna gives Claude direct control of NanoVNA-H vector network analyzers over USB serial. It exposes 78 MCP tools for frequency sweeps, S-parameter measurements, calibration, LCD capture, RF analysis, and 3D antenna radiation pattern visualization.

Capabilities

Measurement

• Frequency sweeps with configurable start/stop/points
• S11 (reflection) and S21 (transmission) measurements
• Marker-based frequency analysis
• Real-time data streaming

Calibration

• Full SOLT calibration workflow
• Save/recall calibration to device flash
• Calibration status verification

Analysis

• SWR, return loss, impedance calculations
• Filter characterization (cutoffs, bandwidth, Q)
• Crystal parameter extraction
• TDR (time domain reflectometry)
• L/C component identification
• Impedance matching network design

Radiation Patterns

• Analytical 3D patterns from S11 data
• Support for dipole, monopole, EFHW, loop, patch antennas
• Pattern import from CSV, EMCAR, NEC2, Touchstone S1P
• Optional Three.js web viewer

Supported Hardware

Device	Frequency Range	Notes
NanoVNA-H	50 kHz - 900 MHz	Original hardware
NanoVNA-H4	50 kHz - 1.5 GHz	Extended range

Note

Other NanoVNA variants using the same USB serial protocol (VID 0x0483, PID 0x5740) should also work.

Architecture

┌─────────────────────────────────────────────────────────┐
│                    Claude Code                          │
│                         │                               │
│                    MCP Protocol                         │
│                         ▼                               │
│  ┌─────────────────────────────────────────────────┐   │
│  │              mcnanovna server                    │   │
│  │  ┌─────────┐  ┌────────────┐  ┌─────────────┐  │   │
│  │  │  tools/ │  │ protocol.py│  │calculations │  │   │
│  │  │ 8 mixins│  │  USB serial│  │  S-param    │  │   │
│  │  └────┬────┘  └─────┬──────┘  │  math       │  │   │
│  │       │             │         └─────────────┘  │   │
│  │       ▼             ▼                          │   │
│  │  ┌──────────────────────────────────────────┐ │   │
│  │  │           NanoVNA class                   │ │   │
│  │  │  (connection lifecycle, auto-reconnect)   │ │   │
│  │  └──────────────────────────────────────────┘ │   │
│  └─────────────────────────────────────────────────┘   │
│                         │                               │
│                    USB Serial                           │
│                         ▼                               │
│              ┌──────────────────┐                       │
│              │   NanoVNA-H      │                       │
│              └──────────────────┘                       │
└─────────────────────────────────────────────────────────┘

Connection Lifecycle

1. First tool call: Auto-discovers USB device, opens serial at 115200 baud
2. Idle < 30s: Trusts existing connection
3. Idle ≥ 30s: Sends sync probe to validate; reconnects on failure
4. Retry: 2 attempts with 300ms delay on cold/stale ports

No manual connect/disconnect needed—the server manages the connection automatically.