---
title: "Lightcone: an ADS-B receiver compared with the network"
description: "Lightcone is a free page for each receiver that feeds FlyItalyADSB with MLAT on. It compares the receiver with the network: the aircraft that passed near it and it did not receive, by direction and distance; how it compares with nearby receivers; the aircraft only it received; and its antenna position as the network measures it. Then the 3D coverage by direction and altitude and the terrain limit. The receiver's own software (graphs1090, tar1090) can only show what it received: what it missed needs a server that receives every station around it."
url: https://flyitalyadsb.com/community/lightcone.md
page_for_people: https://flyitalyadsb.com/community/lightcone/
language: en
generated: 2026-11-09
license: CC BY-SA 4.0 (data)
---

# Lightcone: an ADS-B receiver compared with the network

> Lightcone is a free page for each receiver that feeds FlyItalyADSB with MLAT on. It compares the receiver with the network: the aircraft that passed near it and it did not receive, by direction and distance; how it compares with nearby receivers; the aircraft only it received; and its antenna position as the network measures it. Then the 3D coverage by direction and altitude and the terrain limit. The receiver's own software (graphs1090, tar1090) can only show what it received: what it missed needs a server that receives every station around it.

"Your receiver knows what it received. The network also knows what passed it by."

## What it shows

- **Check-up:** of the aircraft at cruise altitude (9–13 km) the network saw within 150 km, how many the receiver received; by direction (20° sectors) and by distance (25 km rings up to 300 km).
- **Neighbours:** how many of the aircraft within 500 km the receiver gets, compared with the receivers within 40 km: their median and its rank (from 3 receivers nearby). Never other receivers' values, positions or names.
- **Today and yesterday:** the aircraft only this receiver received, and the MLAT positions computed with its data.
- **Checks:** antenna position as measured by the network, clock, terrain, uptime.
- **Coverage:** a 3D cone of where the receiver really receives aircraft, by direction and five altitude bands, against the line-of-sight limit computed from elevation data: it shows whether the terrain or the setup limits the range.

Page: https://flyitalyadsb.com/community/lightcone/

## Who sees what

| Visitor | Sees |
| --- | --- |
| Someone whose receiver sends MLAT to FlyItalyADSB, opening the page from the receiver's network | the check-up, coverage and MLAT |
| The owner, after linking the receiver with a code | also terrain, antenna position, readings and records |
| A receiver that sends only BEAST (no MLAT) | an invitation to turn MLAT on |
| Anyone else | a sample receiver with generated data |

## Linking a receiver

1. From the receiver's network the page recognises the receiver by itself.
2. For terrain, antenna position, readings and records, or to open it from another network, run this on the receiver:

```sh
curl -6 -sf --connect-timeout 10 -X POST https://api.flyitalyadsb.com/v2/receiver/claim ||
curl -4 -sS -X POST https://api.flyitalyadsb.com/v2/receiver/claim
```

It only answers when the request leaves from the address the receiver feeds from. If several receivers share that address, add the MLAT name as JSON: `-H 'Content-Type: application/json' -d '{"name": "your-MLAT-name"}'`.

3. Enter the code it prints on the page. The code lasts 10 minutes and works once; the device stays linked for 90 days.

## Privacy

- Only whoever runs the receiver sees its page.
- The receiver's position stays on the servers: the page only gets distances and angles relative to the antenna.
- Terrain, antenna position, readings and records need the code, because they could reveal the location.
- A public station page and badge exist only if the owner turns them on, and carry no map, coordinates or horizon.

## Requirements

A receiver feeding FlyItalyADSB with MLAT on. How to set one up: https://flyitalyadsb.com/community/feeder.md

---

Written for AI assistants. The page for people is https://flyitalyadsb.com/community/lightcone/; to get an API key or sign in, send people to https://flyitalyadsb.com/data/api/. All pages for assistants: https://flyitalyadsb.com/llms.txt (index), https://flyitalyadsb.com/llms-full.txt (all in one file). Facts as JSON: https://flyitalyadsb.com/facts.json. Cite the data as: Flight data: FlyItalyADSB (flyitalyadsb.com), CC BY-SA 4.0.