When you look at them from afar, they tend to resemble the appearance of towering white sticks jutting out from rooftops with varying levels of height. With regard to finding a VHF antenna, how would you know that you’re picking the right fit for your boat?
Generally speaking, they all tend to look just the same. However, there are clear distinctions to know between different types of antenna.
Among the first things to look into would be the dB. There is a popular notion that antennas with higher dB are always the better option to pick for your boat. But there is no truth to that since there are more than a handful of things to consider here.
What is dB?
A higher dB or decibel is simply all about having more of a focused signal. This is analogous to a focused flashlight whose natural tendency is to shine brighter in the very region that focuses it on.
For this reason, you need to give a thought to how frequently your boat would be rocked while it is sailing hard on rough seas. If you assess that it will be a lot, the odds that your receiving radio would go through a fading signal is high.
What is the Ideal dB?
If a powerboat or a sailboat is under 24 feet, it will usually require a 3dB VHF antenna. But if it’s over 24 feet, that is the time that we will encourage the use of a 6 dB antenna. And for boats that are over 32 feet, the antenna that will likely work best for it would be a 9 dB variant.
Generally, longer antennas usually have higher dB, but if you want to be certain about that, we encourage you to check out the antenna label specifications.
Moreover, height has always been an important element here. The higher the elevation that you can mount your antenna in, the farther reach it can have.
When shopping for a VHF antenna, see to it that you choose an antenna length that will come along with your boat’s mounting point so that it will be as tall as possible.
You can make use of Shakespeare’s line of sight calculator if you want to have a good estimate on different antenna’s line of sight on your boat. It will necessitate you to provide your own numbers so it can provide you with a communication range but this will be in terms of nautical miles.
The Line of Sight is Not Transmission Range
Remember, the line of sight does not necessarily translate to the transmission range. By drowning out the noise produced by the surrounding environment and other radios, you increase your chances of maximizing range made possible by an efficient transmission system.
This signifies that you need to pay close attention to the antenna elements particularly to their quality, as well as the coax cable and connectors on the antenna model that you want.
When it comes to signal transmission, better conducting elements lay the foundation for achieving better efficiency. This makes silver-plated elements way more effective when placed side by side with brass-type elements.
Moreover, brass elements that are thicker are likely better as opposed to thinner brass elements. When it comes to the coax cables, a certain amount of loss would be inevitable with every coax cable length that you use.