On April 23, I reported the alarm on our front stairs going off. I found nothing at the time that could have set it off. I rearmed the alarm at that time (April 23rd) It has been on since and nothing has set it off. Its May 29th so over a month has passed and the alarm remains quiet. So it makes me wonder, more than ever, just what set it off. We rarely use the front stairs except during holidays when I'm carring decorations of one form or another. Normally we use the rear stairs. Otherwise the house has been quiet. Outside, this past week, my wife and I heard loud explosions on two different days; both in the early afternoon. As usual we were the only people in town to hear them. I'm not surprised; it has been so ever since we moved here over 30 years ago. No, I have no idea where the explosions originated; but they were quite loud. These explosions were well outside of the house. One sounded like it waas only a block or so away; the other sounded further off. No they were not firecrackers. I have a pretty well grounded knowledge of firecrackers.