karl riley
Senior Member
Re: neutral on CATV sheaths
Hal, I went to Radio Shack today and got two 75 to 300 ohm transformers. One of them has screw connectors for the 300 ohm flats from the other one, so it's an easy connect. The sheath tested discontinuous and should block low voltage neutral current.
This would be installed on the street side of the ground block and so it will not break the gounding connection of the receiver inside the house, which will still be grounded to the service ground (both its EGC and its cable sheath).
Since the sheath of the incoming cable is grounded at the pole or transformer, and the other side of this double balum is grounded to the building service ground, a nearby lightning strike could cause a voltage difference inside the balums and destroy the balums (cost, $7.48)as it blasts through to the grounding electrode.
Seems like a good solution to the objectionable neutral current on the cable sheath, no? Anyone want to share their opinion tonight? I'm going to the job tomorrow.
Karl
Hal, I went to Radio Shack today and got two 75 to 300 ohm transformers. One of them has screw connectors for the 300 ohm flats from the other one, so it's an easy connect. The sheath tested discontinuous and should block low voltage neutral current.
This would be installed on the street side of the ground block and so it will not break the gounding connection of the receiver inside the house, which will still be grounded to the service ground (both its EGC and its cable sheath).
Since the sheath of the incoming cable is grounded at the pole or transformer, and the other side of this double balum is grounded to the building service ground, a nearby lightning strike could cause a voltage difference inside the balums and destroy the balums (cost, $7.48)as it blasts through to the grounding electrode.
Seems like a good solution to the objectionable neutral current on the cable sheath, no? Anyone want to share their opinion tonight? I'm going to the job tomorrow.
Karl