OT for a sec: US wiring sources of info

[Tony Duell]

>   I once worked in a hospital and repairing the TVs was one of my
> responsibilities. One day we had a call for a TV that won't work. When we
> arrived it was working fine. A little latter we had a call for the same
> thing from the adjacent room. This time we checked closer. We found that
> the TVs were back to back on a common wall and both TVs used the same
> electrical circuit. Somewhere there was an open circuit between the AC
> outlets such that the two TVs were in series so neither one would work
> unless both were turned on! That's why the patients TVs were dead, one
> patient would turn their set off and it would turn both of them off. The
> surprising thing was that both sets worked normal when in series. Very
> surprising since each one was running off 1/2 the normal voltage!

Were they, though?

Obviously, I don't know the details, but the most obvious way this could 
happen on the US mains wiring system would be if one live ('hot') side of 
each socket outlet was wired to each side of the centre-tapped mains. The 
neutral sides of the sockets were linked together, but for some reason 
that connection was not connected back to the centre-tap of the mains 
supply. That would put the 2 TVs in series across the 230V mains. 
Assuming they were similar sets, each would see about 115V.

-tony