On 17/08/07, Howard Winter wrote: > Mark, > > On Thu, 16 Aug 2007 11:55:51 -0500, Mark E. Skeels wrote: > > > Can you guys think of any way a phone line could be induced to go off > > hook via a stimulus external to the phone line (not electrically connected? > > An earthquake shaking the handset off the cradle... a rat gnawing through the insulation... water in a junction box... a nail through the cable... (I > suppose that's electrically connected, strictly speaking)... > > Has anyone checked the cellar to see if there's someone trapped down there, who is trying to signal their plight? > > I think following the cable would be a good plan, to see if there's something obvious causing it. Then again, to see if it's something that isn't obvious! > :-) > > Incidentally, you mentioned interference at the right frequency to dial - that would be 10Hz, rather unlikely to find something that slow, especially if > it's in a non-regular pattern like 9-1-1. Incidentally, in the UK the emergency number is 999, and one reason it wasn't 111 was because cables > swinging about in the breeze could easily short out in that pattern - when they were bare wires, of course. The European standard is 112, and that > works in the UK as well. > In NZ the number is 111 (911 also works) - but we have a reversed pulse dial allocation - so the actual pulse train is the same as 999 IIRC. (Or very close). RP -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist