The node detector is a receptor. It changes its state when either any node
or a specific node is detected. Right-click it to set a nodename to scan for.
It can also receive digiline signals. For example, you can send
<code>{distance=4, scanname="default:dirt"}</code>
to set distance to 4 and scan for dirt. You can omit either parameter.
There is also a command parameter: <code>{command="get"}</code> will respond
with the detected nodename and <code>{command="scan"}</code> will respond with
a boolean using t