"Pierre Desjardins" wrote in message
...
Hi to all

I read somewhere that the dual rhombic could give a gain of almost 27
db using these dimension for 144,2 mHz:

Nowhere near 27 dB.


L1- 29.5 ft, L2- 50.67 ft, X- 52.2 degrees, Y- 37.7 degrees, R1/2 660
ohms noninductive, Ht: 12.29 ft, Elevation angle: 7.5 degrees,
Vertical beamwidth: 5.5 degrees and Horizontal beamwidth: 8.5 degrees.
We did once erect exactly the same antenna. It was about 1 S unit worse than
2x 17 elements F9FT yagi, tested on RX only and for

1 hour when we hastily dismantled it due the snow blizzard . OTOH, -1 S
unit on 34 el yagi is nod bad for piece(s) of wire...


Has anyone ever verified this? Here, using simulation with EZNEC+, I
get about 15 dBi in free space and much lower on real ground. Am I
missing something?

This is about right. My single rhombic for 1296 MHz got pretty much the
same gain and radiation pattern as simulated in NEC2.


Thanks for your answers

73 de Pierre VE2PID

GL de Mario 9A4DE