If this device works, it works well. But the problem is that when the battery is low it shows a FALSE value instead of displaying it. You can connect a new patch cord to the receivers and it will show "adapter not found". This is very uncomfortable for professionals in this field. We have to be able to trust our test equipment. Otherwise we hunt ghosts all day long. I have two. Both did the same. I think one of these is actually dead because it says "no adapter" even after changing the battery. Disappointing.