Always for the Fun and for some tests with the Satellites, I continued the construction of my antennas for the 1296 Mhz with the construction of some Yagis 35 elements. I did not want the elements to cross or be in contact with the boom, I chose the isolated version.
And 35 elements only on a boom of about 3m gives a gain of about 17.8 dBd. Sufficient for me between the ratio of the gain and the length of the boom.
I was inspired by the model and design of F9FT 23cm / 35el., But I built the dipole is symmetrical T rather than a Loop trombone.
To install the distant elements of the boom, I made some tests with supports like Y nylon columns and square support used to fix the ties wraps but it was inconclusive.
Having nothing else, I looked on the Web, supports already built for this kind of application at I0JXX.
Here are the references:
http://www.i0jxx.com/en/52-4mm
ISO15 4
Element diameter 4 mm Boom dimension 15 x 15 mm Distance from boom 40 mm
BOX4JXX
Nylon 6.6 box, it can be bored in order to put in dipoles and connector
Elements: 4mm diameter aluminum rod
Boom: 15mm square, length: 3m
This antenna is easy to build, the only care is the strict respect and the precision of the dimensions. I used EZNEC software - RF SIM 99 - Yagi Calculator by John Drew VK5DJ.
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| H Pattern |
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| V Pattern |
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| Ready for connection and First Tests. |
Next descriptions: 4x12 el. 144Mhz, 4 x 25 el. 432Mhz, Mesh dish 3,2m F / d: 0.4