 4 x 10 Element YU7EF, H/V-pol
|
Traces of echos received with 40W and 4x10 Element
|
Tests with 2m Yagi Antennas
After removing my old 11m dish, I had a nice YL1050 PA for 144 MHz and a 3-phase power supply left unused. I tried to sell it, but nobody was interested, probably because most people prefer LDMOS PA.
After a while I decided to build a yagi array consisting of four EF0210LT antennas, designed by YU7EF. Tests with a single yagi were successful (very low sidelobes and backlobe), receive performance was better than a 14 element 4 wavelength yagi which I had built for comparisons. Much less interferenes from the town nearby.
The single prototype yagi is now mounted on top of my 3m dish in my home QTH.
I can make comparisons now between the single 10 element yagi ( H-pol only) and the 4x10 element yagi array (H/V-pol). I estimate the array beeing around 5dB better than the single yagi, some extra losses by the phasing lines and the additional elements for H/V polarisation are causing gain reduction, therefore less than the theoretical 6dB.
4 x 10 Element YU7EF, H/V-pol
|
Traces of echos received with 40W and 4x10 Element
|
 144MHz Echos with a single 10 Element YU7EF antenna and 1kW
|
TX with single 10 Element YU7EF antenna and 1kW, RX with 4x10 Element |
