Does a cobweb antenna have gain?

A dipole or a CobWebb has a gain of about 5dB over a dipole in free space, (due to ground reflection) or 7dB over an isotropic radiator (7dBi) and will work equally well over the entire band.

How high does a cobweb antenna need to be?

Compact and easy to handle – Around 8ft square. Doesn’t have to be too high – Reasonable performance at 10ft, with 20ft being the ideal.

Is a balun necessary?

Baluns are an essential element in many antenna systems. They enable a balanced antenna or feeder to be transitioned correctly to an unbalanced one like coax that can easily be routed through a building, etc to where it is needed.

What is a balun ham radio?

A balun (balanced line to unbalanced line) is a device that transforms a balanced transmission line to an unbalanced transmission line. Baluns are hooked up to antenna systems to help electricity run smoothly from the ground to the device.

Where do you put a balun?

The balun should be located near the tuner, but still outside, keeping the coaxial cable between it and the tuner about 10 to 20 feet.

Does a balun reduce noise?

Whilst a balun is usually associated with reduced unwanted transmission line radiation (eg. from the feedline and power cord), a balun can also help minimise unwanted noise picked up by your feedline.

What is a 4.1 balun used for?

Based on the above, a 4:1 balun or any voltage-type balun is the wrong choice for use with antenna tuners in multi-band dipole systems. Most tuners use them because they are cheap, easy to build, and because almost everyone else uses them. For antenna tuners or systems with high SWR, we have a special balun.

How do I know what balun to use?

Select a balun closest to the antenna feedpoint impedance (you’ll have to get this from textbooks or modeling), and use it at the feedpoint or where the feedline from the antenna ends. Be sure the feedline between the balun and antenna feedpoint matches the antenna impedance as closely as possible.