> For the complete documentation index, see [llms.txt](https://docs.wingbits.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.wingbits.com/byod/grandfathered-byod-diy-info/theoretical-range-of-coverage.md).

# Theoretical range of coverage

To judge the actual range, one needs to first know what kind of range is even possible for the station's location. 1090 MHz reception requires a direct line of sight through air to what you want to receive, thus depends on obstacles and the curvature of the earth. To get that theoretical range for a location, follow these steps.

{% hint style="info" %}
The first step can be done by anyone running either a BYOD station or an approved hardware station.  The second step is specific to BYOD stations and cannot be done on an approved hardware station.
{% endhint %}

#### **1: Create panorama and look at your outline on heywhatsthat.com**

* Visit <http://www.heywhatsthat.com/>
* Click "New Panorama" at the top
  * For Step 1, set the location (via address or lat/lon)  for your antenna precisely
  * Skip step 2.
  * For step 3 enter the height of the antenna for your install location, leave the radio button as "above ground".
  * For step 4, enter a title and click Submit Request
* Wait for the request to finish and load a new page.
* Scroll down to the map and click the "Up in the Air" button on the top right of the map
* Change the "30000" value below the map to "40000" (this is maximum expected altitude of flights in your area).
  * You can change the altitudes (ft) below the map to view different outlines for your location
  * Those outlines tell you how far you can receive aircraft at the associated altitudes
* Zoom out a few times with the "-" (minus sign) on the map until you can see the theoretical coverage outlines.
* The panorama does not take into account obstacles closer to the antenna than approximately 100 ft, trees are also not considered but can block reception

#### **2: Integrate theoretical range outline into your local tar1090 display**

* On the top left of the page, an URL to revisit the panorama is mentioned.  It will look something like:\
  <https://www.heywhatsthat.com/?view=**JM6Q9FQQ>\*\*
* Replace the XXXXX in the following command with the value after view= in your panorama URL, then run the command on your pi:

```
sudo /usr/local/share/tar1090/getupintheair.sh XXXXX
```

* You should now have a range outline for the theoretical range for aircraft at 40000 ft on your tar1090 map

{% hint style="info" %}
If you wish to turn the outline off or on in tar1090, use the Legend/Layers button on the top of tar1090 screen and select/unselect the "terrain-based range outline" checkbox.
{% endhint %}

<figure><img src="/files/pPHmwRcnUwZA4ugtO4aL" alt=""><figcaption><p>Your actual coverage</p></figcaption></figure>


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