Safety tip of the day

[electronjohn]

I have a broadcast engineering acquaintance who intimately knows what an undischarged filter's capable of. He was working on a balky 20kW FM transmitter...it was the middle of the night & he'd been at it for hours. His most recent attempt at getting it back on the air failed, he got VERY pizzed and flung a wrench in his hands into the transmitter's guts. As bad luck would have it, it landed RIGHT ACROSS the terminals of a big filter (maybe 20uF @ 15kV). The big cap blew the wrench out like it was shot from a gun...hit him in the face, breaking his jaw & taking out 8-9 teeth. It was a Collins like I'm familiar with, so prolly ran about 8,200V @ 3A or so. Owie.

Myself? Only been zapped once...an old Gates 1kW AM got me w/about 3500V @ 500mils. Knocked me right into the wall 3' behind the transmitter. I quit bypassing interlocks that day. Oh...when I was a kid I let a color TV snap an arc right thru my fingernail. Left a cute little hole. Owie.