What is an Arc Gap for AM Antenna Systems

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An Arc Gap for AM Antenna system is a traditional protector for spark radio transmitter that is no longer in use but used to be the norm many years back. A Spark transmitter generates radio waves using an electric spark. This transmitter was the first type introduced during the telegraphy era. Starting from 1887, right until the end of the First World War, it was used to transmit radio frequency.

Arc gaps protect antennas from lighting strikes. Although they may no longer be in use due to modern in innovations, they are still functional and equally reliable for frequency transmission. Moreover, they are very effective in protecting your broadcast equipment from lighting strikes.

How to install an Arc GAP system?

The best way to install an Arc Gap is to fix one onto the 50-ohm input as well as the antenna output. The AM Phasors where connection lines enter each tower should also have an Arc Gap.  For extra protection, another place to install this protection equipment is where the feed lines pass through.

To hold the system in place, it is advisable to fasten it with acorn nuts at each end. You can also include threads in the brackets to make them firmer. You also need to understand the larger and smaller L brackets and what they are made of. The larger L bracket has 4 inches played corners, while the small L bracket is aluminum with threaded features to accommodate hardware made of brass.

Where to install an Arc Gap?

It is advisable to install an Arc Gap where you have the toroidal sample coil or a Delta branded antenna. As for the best location for it, that will be there side of the sample coil where lighting is likely to make an impact. Do note that lighting tends to follow the shortest path possible, so ensure the gap of your antenna is much larger than the arc Gap you use.

If your coil had a Teflon bushing and black, it might be that it has been struck by lightning in the past, eventually leading to metering problems.

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