[QUOTE=a good help]
Quote:
PS1,
Not completely true.If a customer has a doggy appliance(eg tv with a poor earth) it is possible to get increased voltage "back"through the catv...
tell me how the voltage will go down the catv cable please??
eg: no digital stb ntl use are earthed to mains? so how would a faulty tv earth increase the the line voltage?? and even send it back down the catv cable?? the earth that the stb uses is provided by the catv system.. and the tv will be connected by either RF or scart so how can that send more voltage to the ntl network?? answers on a post card please :P
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I know that question was not aimed at me.
The most likely way for mains voltage to be fed down the coax would be from a faulty TV if the TV was connected directly to the network without a set-top (to view bypass channels). As I mentioned in my previous post the isolating capacitors in the TV would have to be short circuit and the ntl isolation box would either be missing or also have short circuit capacitors.
The ntl network is fairly well protected with the isolation box and all the RF equipment earthed at the cabinet to a common point. There would have to be a few of these items incorrect for the network to be put in a dangerous state.
the most dangerous situation I ever came across was a situation caused by ntl themselves. I once moved a mains powered 60VAC power supply prior to replaing it and felt a little tingle. Fortunately I had not removed the dedicated earth bonding cable, as one of the 16th edition qualified backboard builders at ntl had wired the Mains socket incorrectly. I seem to recall earth and neutral were swapped around, I'm not sure if it was a conspiracy to finish me off....
