How long should a VHF antenna be?

A 3- to 4-foot antenna that’s 3 dB is generally recommended for boats under 24 feet. Larger vessels can opt for 12- to 18-foot, 7 to 8 dB antennas. “As a general rule, antenna height should be less than half the length of the boat,” Catoe says.

Does VHF antenna length matter?

The length of your antenna determines how good it is at handling certain frequencies; according to experts, there’s a sweet spot that gives you the best signal. If you use an antenna that’s too long or too short, your signal might cut in and out at times.

How far apart should mobile antennas be?

My rule of thumb is that antennas should be 35-50 feet apart or more if you’re looking at an open space like a warehouse or cubicle farm, less if you are looking at boosting through walls. The best thing to do is not to make assumptions. Start with one antenna and try making calls from different distances.

Is a longer antenna better VHF?

UHF frequencies have a shorter wavelength and therefore, the antenna can be shorter than for an equivalent VHF radio. Theoretically, a longer antenna will have a greater range, but it is far more important for optimal radio performance that the length of the antenna matches the frequency.

Does a VHF radio need an antenna?

VHF antennas are a crucial part of your VHF installation. The main purpose of a VHF antenna is to provide a radiator for the power that the transmitter in the radio produces and to radiate this energy in the correct direction.

Is longer antenna better?

A bigger antenna, properly designed, will always have more gain than a smaller one. And it will be the best kind of gain, much better than using a small antenna and simply overamplifying it, because a small antenna just won’t pull in truly weak signals like this gigantic one will.

Why is the height of a VHF radio antenna important line of sight?

When considering marine VHF radio communications, more important than all other factors is the height of your antenna. The higher you can place your VHF antenna the further you will be able to communicate. Any angle beyond vertical will lessen the performance of your radio signal.

Will two antennas interfere?

No it wouldn’t be multipath interference because a signal reflection from that close isn’t enough distance to have any real measurable delay since RF travels at the speed of light. Are both of these antennas pointing in the same direction? They make combo VHF/UHF units.

What is the minimum desirable antenna separation?

As a general rule, the inside antenna and the outside antennas need 20 feet vertical OR 50 feet horizontal separation. If those distances are not feasible for your application, it can be achieved by doing a combination of the two (E.g, 10 feet vertical AND 30 feet horizontal).

Does a VHF antenna need to be grounded?

VHF antennas that come with an integrated ground plane do not need to be grounded. VHF antennas that do not have an integrated ground plane must be grounded, and their instruction manual will tell you how. Either way, you need to consult the installation instructions for the antenna that you buy.

Is over the air TV UHF or VHF?

These issues are greatly reduced with digital television, and today most over-the-air broadcasts take place on UHF, while VHF channels are being retired.

Why is the length of a VHF radio antenna important?

For the sole reason that VHF devices are line of sight, the power of the signal significantly relies on the length of the antenna (length matters!), so the taller the antenna, the better signal strength and reach!

What is the formula for antenna length?

Calculate the length of the antenna. The formula for calculating antenna length in feet is 468/f, where f is the center frequency.

What is the ideal CB antenna length?

Length – Tall antennas generally work better and get a longer range than short antennas. The higher the antenna goes, the farther your message will go, and you can receive messages from farther away. The ideal length antenna for CB radios is 102 inches (about 8 and ½ feet!) because it is equal to ¼ of a wavelength.

What is the formula for quarter wave antenna?

Figure 2. – a marconi antenna. The formula for quarter wave is L = 71.25 metres / freq (mhz) and in feet L = 234 / freq (mhz). Note the variance from the standard wavelength formula of 300 / freq. This is because we allow for “velocity factor” of 5% and our wavelength formula becomes 285 / freq.

How long should a VHF antenna be? A 3- to 4-foot antenna that’s 3 dB is generally recommended for boats under 24 feet. Larger vessels can opt for 12- to 18-foot, 7 to 8 dB antennas. “As a general rule, antenna height should be less than half the length of the boat,” Catoe says. Does…