Thread: Sharing fixed problem with our telco lines
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Default Sharing fixed problem with our telco lines
On 10/31/2014 12:27 AM, wrote:

Turns out he had two ground rods driven in and for whatever reason there was a ground gradient. A slight ground gradient at power line is not necessarily proof of a fault, depends where they are. And really, we are only talking about interfereing with video which is what, a volt P-P ?


There is not enough information to tell how this was set up. But all
earthing electrodes are required to be bonded together into one system.
That includes any lightning rod system.

The cable shield is grounded to the earthing system at the entry to the
house. The service neutral is also connected to the earthing system. For
overhead distribution I assume the cable drop is grounded at the tap at
the feeder cable. The feed cable is grounded at at least some of the
poles. That puts the cable drop in parallel with the house service
neutral, and the neutral voltage drop will appear on the shield. Only
way I can see to avoid it is if the cable drop is isolated at the source
tap (like transformer coupled). I assume significant 60Hz is removed
with a high pass filter.
What is the signal voltage on cable?


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