Rex Boys said: The apidictor was a stand-alone instrument intended to be fed into a human ear. I cannot visualise ..feed into a computer... used it as a pre-amplifier. > That's the idea. Computer or simple communications device could feed this information to your desk top. Not much advantage if your hive is in the backyard. Big advantage if far away. Your second paragraph suggests that knowledge of an impending swarm is not much good unless you are there when it emerges. In Britain we learn procedures that can be used to prevent swarms > So do we. If we could successfully prevent all swarms, one wouldn't need a warning system (whether an apidictor or some other device). Cheers Jerry