"N4LQ" wrote in message ...
Then how come it doesn't give us 20db of forward gain? I mean, we blocked
20db off the back and applied it to the front and we still only have 5db
of
forward gain. Where did the extra 15db go?

Well... you won't handle it like that. dB aren't preserved in this
fashion. Power is...

The balloon analogy it good. Poke it "in" at one point so there is NO
radiation in that direction. The signal in the "poked-in" direction will be
really low or zero or MANY MANY MANY dB down...hundreds.


However, try this as another way to see it:

Imagine an antenna that radiates equally well in all directions AROUND the
antenna like an ideal vertical. It will have SOME signal strength in all
directions, which is the same.

Now, lets imagine another antenna (more complex and let's ignore how) which
only radiated HALF way around, but equally distributed, just like before.
That is, it cuts off all radiation to one side as though it was cut with a
knife -- and re-distributes the "cut-off power to the "good" half.
Nothing to the "bad" half -- everything to the "good" half.

The good half just went up 3dB, right ... twice the power.

The bad half went to zero. or infinity dB.

You don't conserve dB.

Help ???

--
Steve N, K,9;d, c. i My email has no u's.

N4LQ wrote:
Say a beam has 5db forward gain and a front to back difference of 20db.
Where does the extra 15db go?

In an infinite number of other directions besides that one
single front direction.
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

Cecil wrote,

N4LQ wrote:
Say a beam has 5db forward gain and a front to back difference of 20db.
Where does the extra 15db go?

In an infinite number of other directions besides that one
single front direction.
--
73, Cecil http://www.qsl.net/w5dxp


Haven't you ever heard of the law of the conservation of
decibels, Cecil? :-)
73,
Tom Donaly, KA6RUH

N4LQ has been a licensed ham since 1964, I would dare say he already knew
the answer to this goofy question and was just looking for some funny
responses.....

Mark W4UDX


"N4LQ" wrote in message ...
Say a beam has 5db forward gain and a front to back difference of 20db.
Where does the extra 15db go? I mean, if you loose 20db off the back on
transmit, I assume you also loose that much on receive. What happened to
the
20db? Did it burn up as heat? What am I missing here?

--
Steve

Forgot to mention.... it kinda reminded me of when that one guy who was
looking for a 160M HT...

Mark W4UDX


"W4UDX" wrote in message
...
N4LQ has been a licensed ham since 1964, I would dare say he already knew
the answer to this goofy question and was just looking for some funny
responses.....

Mark W4UDX


"N4LQ" wrote in message ...
Say a beam has 5db forward gain and a front to back difference of 20db.
Where does the extra 15db go? I mean, if you loose 20db off the back on
transmit, I assume you also loose that much on receive. What happened to
the
20db? Did it burn up as heat? What am I missing here?

--
Steve

On Wed, 16 Jun 2004 19:06:30 -0400, "W4UDX"
wrote:

Forgot to mention.... it kinda reminded me of when that one guy who was
looking for a 160M HT...

Mark W4UDX

The transceiver is portable, except for the antenna. ;-)

Happy trails,
Gary (net.yogi.bear)
------------------------------------------------
at the 51st percentile of ursine intelligence

Gary D. Schwartz, Needham, MA, USA
Please reply to: garyDOTschwartzATpoboxDOTcom

Why NOT ??? Afterall, the "Gibson Girl" worked on 500 kHz !! Now THAT is
REAL QRP DX!
;) Jim NN7K


Mark wrote:
Forgot to mention.... it kinda reminded me of when that one guy who was
looking for a 160M HT...

Mark W4UDX

W4UDX wrote:
Forgot to mention.... it kinda reminded me of when that one guy who was
looking for a 160M HT...

We had quite a few 160M HT's right after WWII, thanks to MARS
and military surplus equipment.
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

I bet they didn't have a rubber antenna with a BNC connector....


"Cecil Moore" wrote in message
...
W4UDX wrote:
Forgot to mention.... it kinda reminded me of when that one guy who was
looking for a 160M HT...

We had quite a few 160M HT's right after WWII, thanks to MARS
and military surplus equipment.
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

W4UDX wrote,
Message-id:

I bet they didn't have a rubber antenna with a BNC connector....


"Cecil Moore" wrote in message
...
W4UDX wrote:
Forgot to mention.... it kinda reminded me of when that one guy who was
looking for a 160M HT...

We had quite a few 160M HT's right after WWII, thanks to MARS
and military surplus equipment.
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----


They were probably called "walkie-talkies," too. Who thinks up the names
for things like this?
73,
Tom Donaly, KA6RUH