The Chirp SDK's audio transmission properties are configured by the licence that the SDK is using. By default, two default licences are available within the Chirp Admin Centre: standard, which uses the audible range, and ultrasonic, which broadcasts in the near-ultrasonic range.
To switch to the ultrasonic licence:
- Sign in to the Chirp Admin Centre
- Within Applications, navigate to the Ultrasonic licence > Download.
The licence file will be downloaded as ultrasonic.lic
- Modify your Chirp application to use this licence rather than the default.
How to do this varies between SDKs; please consult the language-specific SDK docs for more information. For most SDKs, you need to open the licence file in a text editor, and copy and paste the contents into the chirp_licence parameter.
Now, restart your application and your Chirp transmissions will immediately begin using the near-ultrasonic range.