On Sat, 10 Apr 2004 01:56:02 +1000, Gerhard Beulke
wrote:

Hi,

I couldn't find any better Newsgroup to ask this question.
It's about a TV antenna.
When I try to capture a video from a VCR (the VCR is connected to the
antenna), I get a humming audio signal.
When I unplug the aerial cable, it's gone.
The antenna is installed on the roof and is proper earthed. In between
is a booster. I don't know if the booster causes the trouble but it
shouldn't.

The humming sound is only there when the VCR is connected to the PC (via
firewire) and the aerial cable is plugged into the VCR.

Any tips how to solve the problem would be greatly appreciated.

73
Gerhard Beulke
VK-DG1EHK

Hi Gerhard,

One way that is quick, but not always effective, is to put a "ground
breaker" between your equipment's power supply and the mains. I'm not
sure if this is available for European AC connectors.

Another way is to use extension cords so all equipment that is powered
connects to the same mains outlet.

You say the antenna is "properly grounded." This is suspicious. Does
it have a wire going to the SAME ground (earth) connection as the
mains? If not, then connect the two together. If the first two don't
work (and even if they do), your problem is probably from this "proper
ground." The reason for the name "ground loop" is that you have two
different paths to ground (two different ground connections separated
by earth).

73's
Richard Clark, KB7QHC