radio and ng-model

HTML

<body ng-app="app">
<div ng-controller='controller'>
<input type = "radio" ng-model = "oSelected"  ng-value = "aData[0]">
<input type = "radio" ng-model = "oSelected"  ng-value = "aData[1]">

<div>test:     {{oSelected}}</div>
</div>
</body>

JavaScript

app = angular.module('app',[]);

app.controller('controller', function($scope){
    $scope.aData =[{tipo:"EXT"},{tipo:"INT"}];
    
    $scope.oSelected = $scope.aData.find(x => x.tipo === "INT");
});