“John quickly tapped his tablet a few times after a few moments he announced, “I have located a signal.” The officer’s jaw dropped, “How did you do that? We have been scanning for hours.” John casually explained, “Some tablets have an anti-theft device. When the tablet is turned off they give off a really weak short range signal on a specific frequency. The signals are powered by an internal battery and are intended to last a very long time. The purpose is for times like this, so the tablet can be located.”_Spidersilk the novel