New Twiddle

controllers.application\.js

import Controller from '@ember/controller';
import { tracked } from '@glimmer/tracking';
import { action } from '@ember/object';

export default class ApplicationController extends Controller {
  @tracked valid = false;
	@tracked value = false;

	get trueVal() {
    return this.valid && this.value;
  }
  get notVal() {
    return this.valid && !this.value;
  }

	@action
  setVal(val) {
    this.valid = true;
    this.value = val;
  }
}

templates.application\.hbs

<input type="radio" name="drone" value="true" checked={{this.val}} {{on "click" (fn this.setVal true)}}>TRUE
<input type="radio" name="drone" value="false" checked={{this.notVal}} {{on "click" (fn this.setVal false)}}>FALSE<br>

VALUE:{{this.value}}<br>
VALID:{{this.valid}}

twiddle\.json

{
  "version": "0.17.1",
  "EmberENV": {
    "FEATURES": {},
    "_TEMPLATE_ONLY_GLIMMER_COMPONENTS": false,
    "_APPLICATION_TEMPLATE_WRAPPER": true,
    "_JQUERY_INTEGRATION": true
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.1/jquery.js",
    "ember": "3.18.1",
    "ember-template-compiler": "3.18.1",
    "ember-testing": "3.18.1"
  },
  "addons": {
    "@glimmer/component": "1.0.0"
  }
}