Text input in radio group

This project tests how a form can include radio buttons and have the last item be an input field.

Current issue

Binding vm.appModel.amount to the input field and the different radio button selections will work: the data used upon clicking on the submit button will be valid.

However, if the user clicks in the text input and starts typing, the radio button loses it's checked value, even if many checks are in place on the text input to keep the checked value set to true:

  ng-focus="isManualInputSelected = true;"
  ng-change="isManualInputSelected = true;"
  ng-click="isManualInputSelected = true;"

On the radio input, this should keep it as activated, however doesn't:

  ng-checked="isManualInputSelected"