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Antenna Plans

2 Elements Yagi for FM Broadcast band center at 107.1Mhz

2 Elements Yagi Build for FM Broadcast Band 104-110Mhz

This antenna build is for FM broadcast band, the center frequency of this antenna is on 107Mhz as measured from 104 to 110Mhz with less than 1.5:1 SWR across those frequencies.

Materials

The materials required to successfully build the antenna are:

1″ x 1″ aluminum square tube
3/8″ anodized aluminum tubing
#12 AWG solid wire for the gamma match (Watch building the Gamma Match video here)
Suitable screws and nuts
Different sizes of shrinkable tubes

The antenna placement and mounting are cut through the 1″x1″ aluminum square boom. The elements are inserted through the boom and secured by a mounting screw at the center. A gamma match bracket is made from a piece of aluminum scrap to form L and cut at the center to hold the gamma match in place. See antenna measurements.

Antenna Measurements

Antenna Pattern and Gain from 4Nec2

Expected pattern and SWR
Horizontal Pattern beamwidth / gain and front to back ratio
Vertical Pattern beamwidth / gain and front to back ratio

Frequency response and VSWR testing video