Shielded Loop Antenna / Yagi-Uda array of loops

It is plenty of article on home builds antenna onto the internet. Most of them are for antenna that can work for both emission and reception.

We will see here two different designs for reception into the FM and TV band. Those 2 designs are using the same base type of antenna: the loop antenna.

Shielded loop

A crude representation of a shielded loop:

The principle is the same than for a loop. From wikipedia: a continuous conducting path leading from one conductor of a two-wire transmission line to the other conductor. All planar loops are directional antennas with a sharp null, and have a radiation pattern similar to the dipole antenna with E and H fields interchanged.

The main advantages of loops antenna are tree:

1) An outstanding signal quality. It is a simple design that perform very well.

2) For large loops, higher gain (about 10%) than the other forms.

3) Large loop antennas are less susceptible to localized noise, partly due to their lack of a need for a groundplane.

The advantage of a shielded loop over a non shielded one:

4) The electric interference from the big city (streetlights, television's , cars etc...) have no influence on the received signal.