> >Where does ALL of the energy go?
> It goes into rec.radio.amateur.antenna to be argued about forever!
> Please, please, not here too... 73 from Ian G3SEK
A friend who engages in sophisticated physics discussions says they insist
upon clear goals and a check-off when some elements are agreed upon so as
to actually reach closure. Here is my effort towards that end:
1. The more gain the antenna has the more the TX signal is magnified.
2. The more gain the antenna has the more the RX signal is magnified.
3. The only element in the system providing gain (following the final
active
amplification stage of the TX) is the antenna.
4. The energy delivery system between the TX and antenna always contains
an element
(or elements) of loss which result in less signal getting from the TX
output to the
antenna.
5. The energy delivery system between the RX and antenna always contains
an element
(or elements) of loss which result in less signal getting from the
antenna output to the
RX.
6. A mismatch of impedances anywhere between the output of the TX finals
and the
antenna terminals will have the following consequences (to varying
degrees):
a. Some energy will be reflected backwards into the energy delivery
system from the
antenna terminals.
b. Some energy will be reflected backwards into the energy delivery
system from the
point of any non-antenna mismatch (e.g. tuner, local or remote
switch, improperly
installed connector, improper connector).
b. Some energy will be lost to misdirected radiation by non-antenna
elements in the
system on the first pass from TX to Antenna.
c. Additional energy will be lost as misdirected radiation as it again
traverses the
system due to reflection(s).
d. Where there is loss of any sort in the system (and there always is
in the real world),
some additional energy will be lost as it traverses the system due
to reflection(s).
7. This all means that the design of energy delivery systems for
controllable and
predictable TX, RX and antenna systems should seek to avoid loss and
mismatches.
8. This also means that energy delivery systems designed for less
controllable and/or
predictable TX, RX and antenna systems should seek to mitigate
mismatches and to
minimize the addition of any elements of loss or mismatch (such as the
20+ pl-259/so-
239 connectors one recent poster to TowerTalk described as causing
significant
losses in his system).
Sure hope this helps to facilitate progress towards clarity.
73, DavidC AA1FA
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