As per the title, all the photos are in the link
I did some googling some time back and found no info on how a coil between a 1/4 wave section and a 5/8 wave section will give the necessary 180 degrees of delay or if a coil can be used this way to make it work as a collinear
as we know a 1/4 wave antenna doesn't need a matching device nor does it if you lengthen it every multiple of a 1/2 a wave is 1/4 wave then 3/4 wave and so on
this antenna is 7/8 long overall.. is not the coil making it act like a 1-1/4 wave as far as matching is concerned by just adding inductance and nothing else
if the coil is giving it 180 delay its a cunningly simple design where a sample coil matches it to a 50 ohm and makes it a collinear at the same time
link
I did some googling some time back and found no info on how a coil between a 1/4 wave section and a 5/8 wave section will give the necessary 180 degrees of delay or if a coil can be used this way to make it work as a collinear
as we know a 1/4 wave antenna doesn't need a matching device nor does it if you lengthen it every multiple of a 1/2 a wave is 1/4 wave then 3/4 wave and so on
this antenna is 7/8 long overall.. is not the coil making it act like a 1-1/4 wave as far as matching is concerned by just adding inductance and nothing else
if the coil is giving it 180 delay its a cunningly simple design where a sample coil matches it to a 50 ohm and makes it a collinear at the same time
link
G-MAX - 10/11 meters antenna for Radio Amateurs
Grazioli G-MAX is a Ground Plane Collinear antenna for the 10 or 11m band. Extremely robust, high performance and with a very low radiation angle.
www.grazioliantenne.com