floating earth

[lookininuk]

hi all,
hope this isn't going to sound like a daft question. I have googled, Wiki'd etc but am still none the wiser. I am trying to feed my secondary Sky output into my tv card on the pc. I have fed VHS and camcorder into it with no problems but it isn't overly happy with Sky. I have a lot of what looks like interlacing that i have tried filtering out but can't. During much muttering and fiddling, checking cable joints etc i found that as i disconnected the ariel cable i got a mild shock from any of the joints as they parted company. I asked a sparky from work who told me i have a floating earth. As i said above i have tried doing my own research but am as clueless as i was before. Is it easy to trace, expensive to fix etc?? ANY help appreciated at this point.

 

[Jaymack]

The sky decoder feeds a voltage on the cable, to the transponder in the dish, this is probably the cause of your shock.

Jaymack

 

[lookininuk]

thanks for the reply jaymack but i have done a little more research, turned off the voltage to the RF2 and it has made no difference. I have tried swapping the primary and secondary feed to see if that makes any difference with no result Had a fiddle with the multimeter (first time without getting zapped too!) and i seem to be getting a backfeed from the tv card. Can't specify voltage but it's enough to hurt. No problem until i pick up the other cable to join the two then owwww!

 

[SparkyMarky]

I have the same problem, and I've never really got to the bottom of it. I first noticed it when I was leaning on my PC case to plug the aerial into the back and got some tingling/mild shocks from my contact with the case. When I'm plugging and unplugging the aerial connections from the TV, video or PC I just be careful not to be touching anything else which is grounded or I get a noticeable shock. At the time I discovered the problem I was going to look at various options to solve the problem, including bonding the aerial sheath to hold it down to the same potential as the electrical earth (a hi-fi buff told me that they do similar things to reduce interference) but I never got around to it. Having said all that, I get a perfect TV picture even with the effect still present so I'm not sure that this is the cause of your interference problem....