> For the complete documentation index, see [llms.txt](https://headtracker.gitbook.io/head-tracker/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://headtracker.gitbook.io/head-tracker/getting-started/wiring/option-2-wired.md).

# Option 2 - Wired

There are two currently supported wired methods. Using PPM or SBUS. The wiring is the same if your connecting directly from the head board or using the bridged method (Option 3)

PPM is the most common and is supported by most radios that have a trainer input.

{% content-ref url="/pages/-Md5qpw\_1W0gWNnOdnhd" %}
[Pulse Position Modulation (PPM)](/head-tracker/getting-started/wiring/option-2-wired/pulse-position-modulation-ppm.md)
{% endcontent-ref %}

SBUS is a digital serial protocol. It is supported as a trainer input on some OpenTx radios, is quite fast and always sends 16 channels.

{% content-ref url="/pages/-Md5qlCOWXHzuGSyCeop" %}
[Serial Bus (SBUS)](/head-tracker/getting-started/wiring/option-2-wired/serial-bus-sbus.md)
{% endcontent-ref %}


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