How long is a 1/4 wave 2 meter antenna?
This element is 1/4 wavelength long, or about 19 inches for the 2 meter band.
How long should a 2m antenna be?
A 2m J-pole is about 60″ / 1.5 m long. I’ve used a 2m J-pole at HT power levels, and it makes a great antenna.
How much gain does a 1/4 wave vertical antenna have?
With a normal sloped roof shape and mid-car size ground, the 1/4 wave has -6.59dBi at 2 degrees TO. Maximum gain is 3.05dBi.
Does a 1/4 wave antenna need a ground plane?
Does a 1/4 wave antenna need a ground plane? Answer: Yes. All 1/4 wave antennas work best if they are installed in the center of a metal ground plane with at least 1/4 wave length radius (1/2 wave length diameter: ~6 inches for 900Mhz and ~3 inches for 2.4Ghz); larger is better.
What is the difference between 1/4 wave and 1/2 wave antenna?
No Ground plane is required for 1/2 wave antenna while its required for 1/4 wave antenna. More energy will be transmitted horizontally in 1/2 wave antenna compared to 1/4 wave antenna. Half wave antenna will be taller is size and would therefore be able to avoid more obstacles than quarter wave antenna.
How long is a 1/2 wave 2 meter antenna?
The higher the frequency, the shorter the wavelength. Most commercially available antennas come in length equivalent from 1/4 to 5/8’s of a full wavelength. This means that if you want to run a 2m rig (144’ish Mhz),a half wavelength antenna would be 3.3” long, and 3.3 ft is very manageable for vehiclular operations.
Is a full wavelength antenna better?
It’s length (half of the wavelength) gives you the better performance than other lengths…..
How do you measure the length of a 1/4 wave antenna?
1/4 wave length antenna take 300 and divide by the frequency. So 150 MHz becomes 2 meters, 300 MHz becomes 1 meter, 600 MHz becomes 1/2 meter. Then take the length in meters and multiply by 3.28 to convert to feet (unless you want to remain metric). Take that result and divide by 4 for 1/4 wavelength.
How long should a VHF antenna be?
Marine VHF Antenna Height and Strength 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.
Which is better half wave or full wave antenna?
It’s length (half of the wavelength) gives you the better performance than other lengths….. It may be gain, efficiency, directivity, return loss, etc….. I got the following picture from a book. I think the gain of the half wave dipole is higher than the full wave length antenna.
Does a 1/2 wave antenna need a ground plane?
Answer: No. The 1/2 wave antenna (also called a dipole antenna) is built of two 1/4 wave elements that interact with one another to launch the electro-magnetic wave. It does not require a ground plane to work efficiently.
What is a 1/4 wave ground plane antenna?
That’s the the 1/4 wave ground plane antenna. Today we’re going to build a simple ground plane for the VHF 2 meter band. Ground plane antennas are easy to recognize by their appearance. First off you’ll notice the radiating element. This element is 1/4 wavelength long, or about 19 inches for the 2 meter band.
What is the formula to make a 6 meter antenna?
You can also make this antenna for other bands also, 6 meter, 1.25 cm, or even the 70cm band. Just use the formula 234 divided by frequency for the length of your elements.
How many radials are in a 2 meter wavelength?
This element is 1/4 wavelength long, or about 19 inches for the 2 meter band. Next up are the ground radials. a ground plane will often have three or four radials, each 1/4 wavelength long.
How many watts do you need for a ground plane antenna?
This little ground plane will work with a handheld or a high power base radio, so don’t fear putting 50 watts or more power. You can also make this antenna for other bands also, 6 meter, 1.25 cm, or even the 70cm band.