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Installing my 40-80m TXloop.
pa0nhc 20161211

My roof is abt. 7 x 10m, made of concrete, with thick foam insulation, a plastic sheet, and gravel. The roof contains mains power cabling, TV coax and telephone line.

The loop itself is capacively balanced, to make it more insensitive for reception of E-field noises, and to reduce BCI and TVI completely. The isolators are pieces Trespa plate.

At only 2.5m distance from the loop is my VHF antenna, and at abt 8m distance is a 45m x 4.75m glass wall in aluminum grid.

The wooden loop mast is painted with outdoor wood paint, and clamped onto a 60cm x 60cm x 1.2m satellite dish foot with concrete tiles to stabilize it. Three 4mm guy wires are connected to the mast top. Two (red) polyester guy wires onto the ends of the upper horizontal beam prevent "no-shaking". TIP : Best use pre-stretched polyester flags line. It does not become brittle in UV environments, and will not stretch.

If i should build a new loop, i should screw three horizontal beams to the mast, to support the upper, middle and lower parts of the loop. It should make the whole more ridged and prevent torque to the copper loop in heavy winds.

Stainless steel and galvanized steel hardware in contact with aluminum were protected against corrosion with spray Tectyl. Concrete tiles loosely placed over the coaxes prevent rattling.

At short intervals, ferrite clamps over the cables damp mantle currents, preventing influencing to the radiation pattern of the loop, and coupling injection of noises from mains lines which run inside the roof. Do not use one clamp over two cables, as you create a transformer.

To minimize damage in case of lightning nearby, an 2x20mm2 aluminum strip connects the loop-foot to the VHF mast base, and from there to the steel construction of the atrium roof. 

At the glass wall,  once inside, all cables are grounded onto the steel roof construction, using professional over voltage arrestors in the coaxes, and double action surge diodes and noise filters for the command cable. The steel construction is connected to the steel reinforcement in the concrete walls and the supporting vertical columns. And finally grounded in the soil. It is the best noise-free and safety solution available here.

Once inside the house, both coaxes end in surge arrestors. The motor lines end with noise filters and double acting over voltage diodes. The mains-safety "ground" is disconnected for noise reasons.

All equipment is grounded to a 2x20mm2 aluminum "ground rail" screwed behind the desk. This "ground rail" is, via the coax screenings, connected to the noise free steel construction of the atrium roof.






Main grounding point to the steel construction of the atrium roof with surge arrestors.