I remember in school, we'd often hear the TV whine and know we were watching a tape in class that day without needing to look up at the TV (mounted high in the

I remember in school, we'd often hear the TV whine and know we were watching a tape in class that day without needing to look up at the TV (mounted high in the corner by the ceiling.) The teachers used to wonder how we knew and didn't believe us when we said we could hear powered on TVs.