infinite_observables.ts

export class TestComponent {

  constructor(private element : ElementRef) { }

  interval: Subscription;
  click: Subscription;

  ngOnInit() {
    this.intervalSubscription = Observable.interval(1000).subscribe(console.log);
    this.clickSubscription = Observable.fromEvent(this.element.nativeElement, 'click').subscribe(console.log);
  }

  ngOnDestroy() {
    this.intervalSubscription.unsubscribe();
    this.clickSubscription.unsubscribe();
  }

}