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Yes, these gain figures for these antennas are only accurate in freespace.

This happens all the time. Its not that any of your sources are necessarily wrong, but how one antenna functions in one environment or orientation will vary if the same antenna is put in another orientation/environment.

If you take a 1/4 wavelength vertical antenna, and angle its radials down, the more the radials are angled down the more the antenna acts like a dipole. In freespace said 1/4 and 1/2 wavelength antennas will act very differently to each other, and from how they each act in the presence of an earth. In the presence of said earth, the radiation pattern is dominated by the earth's characteristics, as well as how high the antenna is above the earth.

If you truly want to understand antenna theory, I highly suggest getting a copy of the ARRL Antenna Book, I hear a new version is due out, and they are all very good at explaining how antennas work, and they are written with the average ham in mind, not engineers... The newest editions of the book are imho the best.

The DB

<blockquote data-quote="The DB" data-source="post: 528673" data-attributes="member: 21346">Yes, these gain figures for these antennas are only accurate in freespace.This happens all the time.&nbsp; Its not that any of your sources are necessarily wrong, but how one antenna functions in one environment or orientation will vary if the same antenna is put in another orientation/environment.If you take a 1/4 wavelength vertical antenna, and angle its radials down, the more the radials are angled down the more the antenna acts like a dipole.&nbsp; In freespace said 1/4 and 1/2 wavelength antennas will act very differently to each other, and from how they each act in the presence of an earth.&nbsp; In the presence of said earth, the radiation pattern is dominated by the earth&#039;s characteristics, as well as how high the antenna is above the earth.If you truly want to understand antenna theory, I highly suggest getting a copy of the ARRL Antenna Book, I hear a new version is due out, and they are all very good at explaining how antennas work, and they are written with the average ham in mind, not engineers...&nbsp; The newest editions of the book are imho the best.<a href="http://hittman.us" target="_blank">The DB</a></blockquote>

[QUOTE="The DB, post: 528673, member: 21346"] Yes, these gain figures for these antennas are only accurate in freespace. This happens all the time. Its not that any of your sources are necessarily wrong, but how one antenna functions in one environment or orientation will vary if the same antenna is put in another orientation/environment. If you take a 1/4 wavelength vertical antenna, and angle its radials down, the more the radials are angled down the more the antenna acts like a dipole. In freespace said 1/4 and 1/2 wavelength antennas will act very differently to each other, and from how they each act in the presence of an earth. In the presence of said earth, the radiation pattern is dominated by the earth's characteristics, as well as how high the antenna is above the earth. If you truly want to understand antenna theory, I highly suggest getting a copy of the ARRL Antenna Book, I hear a new version is due out, and they are all very good at explaining how antennas work, and they are written with the average ham in mind, not engineers... The newest editions of the book are imho the best. [URL='http://hittman.us'][COLOR=#000000]The DB[/COLOR][/URL] [/QUOTE]

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