Observable subject -

sample_subject.cs

/* Use with caution! http://davesexton.com/blog/post/To-Use-Subject-Or-Not-To-Use-Subject.aspx */
public class SomeClass {
    private readonly Subject<int> triggerableObservable =
      new Subject<int>();

    public IObservable<int> TriggeredObservable => triggerableObservable.AsObservable();

    private IDisposable subscription;

    public SomeClass()
    {
      SetObservables();
    }

    private void SetObservables()
    {
      subscription = TriggeredObservable
        .Throttle(TimeSpan.FromMilliseconds(750))
        .Subscribe(x => { });
    }
}