Installing Your License

  1. After purchasing QTH, you will recieve your license in your email. Please save the attached file to a temporary location on your computer.
  2. Open QTH Preferences, QTH → Preferences... Station Preferences
  3. Click the License Center button and the License Center sheet will open up. License Center
  4. Click the Import License... button and a file picker window will appear. Import License
  5. Navigate to the license file on your computer and select it.
  6. Enter the password that you supplied when requesting the license.
  7. Click Open and the license will be imported.
  8. Click Ok to return to QTH Preferences

Continue on to Local Station Setup

Technical Details

Licenses for QTH are issued as X.509 certificates that are signed by the QTH Certificate Authority (CA). In addition to containing the standard attributes, such as your name, country, state, etc, they also contain a special attribute, callsign which was established by LoTW.

QTH will only recognize certificates that are signed by the QTH CA. However, once you have obtained a certificate, you may use it on as many computers you wish.

Warning Your certificate contains YOUR CALLSIGN in addition to your name and email address. If you give it to someone else, they will be able transmit as you.

It is my hope that, in the future, the certificates issued by QTH will also be recognized, in addition to LoTW certificates, as a trusted authentication mechanism when connecting to APRS-IS, replacing the insecure passcode system.

Uninstalling a license

Licenses for QTH are installed in the macOS Keychain.

To uninstall a QTH license,

  1. Open Keychain Access.app.
  2. Select My Certificates in the left Category panel.
  3. Look through the list of certificates until you find the one with your name that is Issued by: QTH Application CA
  4. Press the delete key or right click and choose Delete "<name>"
  5. Confirm the deletion by clicking the Delete button on the resulting popup.
  6. Restart QTH