Testing out the MFJ-5008 Ultrasonic Receiver w/ Parabolic Reflector at Bracken Bat Cave in Central Texas! Bonus visit to Natural Bridge Caverns included! The MFJ-5008 isn't just for identifying pesky power line noise & mechanical noise, but can also be used as a 'Wildlife' Noise Detector! Bats & all sorts of other creatures that emit sounds in the ultrasonic range. Stay tuned to SignalSearch for more videos on the MFJ-5008, including investigating some pesky power line noise & other culprits that make your ears go ARGHHH! 73 K5ACL 'SignalSearch'