Thread: true or... ?
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Old September 5th 09, 12:14 AM posted to rec.radio.amateur.antenna
-.-. --.-[_2_] -.-. --.-[_2_] is offline
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First recorded activity by RadioBanter: Dec 2007
Posts: 35
Default true or... ?


"Richard Clark" ha scritto nel messaggio
...
Hi OM,

Efficiency in percent (%) is simple math: 100 * PowerOut/PowerIn

In decibels, I won't show the math, I will give some example:
100% is 0dB
95% is -0.22dB
90% is -0.46dB
80% is -0.97dB
50% is -3dB
10% is -10dB

Look at your S-Meter. If any station added 5% efficiency, going from
95% to 100%, then your S-Meter would shift 0.22dB. The needle of your
S-Meter is probably more than 1dB thick when you look at it. The
needle would then move 1/5th of its thickness when a station adds 5%
efficiency.


Straight and clear. Well, maybe my knowledge of physics and mathematic can
go a bit far, including understand e.g. ground losses, path loss in free
space, takeoff angle, feed point impedance and other silly things regarding
antenna world but sorry, Maxwell equations are a bit harder for me



I have been in the military - antennas work the same there too. I was
a teacher of RF Systems (LF/MF/HF/VHF/UHF/SHF). There is no magic
knowledge hidden by the government.


Well, i'm ever a optimistic mind... i just think that maybe tomorrow i can
use something better antenna thanks to MIL research ... like a trick to
build a 160m yagi in the same space of a 40 m yagi of course, just
joking... OTH radar DUGA-3 in Prypiat, ex USSR now Ukraine, is a good
example for me, MIL also need big antenna system.

Anyone can write a useless PDF. Anyone can get a useless patent too.
I have observed patent holders who post here that have forgotten their
own patent numbers, their own patent claims, their own URLs, their own
email addresses, and their own theory. Talk about a waste of time,
but it is wasted with the vigor of a seven year old. It would seem
that wasting time, money, and signal power was equivalent to earning a
PhD in Einsteinomics and advanced Gaussology.


Well, let say that *today* is more obvious and easy that this total waste
happen. Globalization and the internet make very easy for timewasters to get
a large public for the things they are saying/writing/claiming. And the
same, in a reverse way, happens to the skilled people, that have occasions
to read tons of wrong assertions on the internet. Many years ago the worst
case is to listen to timewasters on a local repeater or on a 40/75/80 meters
net.
When i don't understand something, the first thing i do is ask, ask and ever
ask.

Unfortunately, today is easy in the same manner both turning on a computer
and turning on a radio to communicate with other people.
Unless you don't have a wireless connection, the computer have as a bonus
that don't need any kind of antenna.

Thanks for your time,

-.-. --.-, Cristiano, Italy.