On Tuesday, October 16, 2012 10:54:02 AM UTC-5, Boomer wrote:
I don't have any of the (G5RV) math for you.

Allow me to provide it based on EZNEC simulations and VK1OD's transmission line loss calculator. The G5RV will be compared to a 127 foot coax-fed dipole, both at a height of 40 feet and both antenna systems resonant at 3.72 MHz.

The 127 foot dipole has a maximum gain of 6.42 dBi at TOA of 90 degrees.
The G5RV dipole has a maximum gain of 6.06 dBi at TOA of 90 degrees.

The 127 foot dipole has a gain of 4.65 dBi at an elevation angle of 45 degrees.
The G5RV has a gain of 4.37 dBi at an elevation angle of 45 degrees.
The dipole beats the G5RV by 0.28dB

The 127 foot dipole has a resonant feedpoint impedance of 59 ohms at 3.72 MHz.
The G5RV has a feedpoint impedance of 33-j355 ohms at 3.72 MHz.

For 30' of RG-213, the 127' dipole has 0.093dB loss.
For 30' of 300 ohm twinlead, the G5RV has 0.89dB loss.
The 127' dipole beats the G5RV by 0.8dB

For another 50' of RG-213, the 127' dipole has 0.175dB loss.
For 50' of RG-213, the G5RV has 0.241dB loss.
The 127' dipole beats the G5RV by 0.066dB

The 127' dipole beats the G5RV by 1.15dB which is 20% of one S-unit. Human ears can barely detect a 1dB change.

So please explain to us how one signal that is 1.15dB lower than a second signal can "disappear into the noise level" and why your ears are so much better than the ears of normal homo sapiens.

Some hams think that -1.15dB on 75m (20% of one S-unit) is a rational compromise for an antenna that also works well as is on 40m, 20m, and 12m.
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73, Cecil, w5dxp.com