Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Old August 17th 04, 12:40 AM
 
Posts: n/a
Default

Richard I need more explanation than that because power is somewhat
irrelevant.
Radiation in my mind (and I must be now worst off than I really thougt) is
accelleration and decelleration of current
which is certainly not power which in my mind is Isquared R. Thus if voltage
is increased current decreases
and therefore radiation decreases.( see effects of very close coupling of a
parallel circuit)
I really do not know where you are coming from, it seems so glib! This is
not meant in a demeaning way, I just
don't want to mix apples with oranges at this point in time. .
Current through a member travels at a constant speed but with cyclic
variations
in radiation. Travel in a circle is also at constant speed but with a
CONSTANT radiation per unit length.
Where exactly is the error in my logic? I suspect it has to do with relative
phase angles but I need it explained
in every day language
regards
Art

"Richard Clark" wrote in message
news
On Mon, 16 Aug 2004 20:31:03 GMT, "
wrote:

If I am incorrect I need to understand why


Hi Art,

Because "Extra" in the budget does not balance.

If you get more power OUT because it is going in a circle, then you
FIRST have to put more power IN to get into that same circle. There
is no extra left.

73's
Richard Clark, KB7QHC



  #2   Report Post  
Old August 17th 04, 01:12 AM
Richard Clark
 
Posts: n/a
Default

On Mon, 16 Aug 2004 23:40:12 GMT, "
wrote:

Richard I need more explanation than that because power is somewhat
irrelevant.


You then broach the remainder of your post in terms of acceleration -
which requires power, and deceleration which begats power.

There is no room for "extra" in the power budget.

Radiation in my mind (and I must be now worst off than I really thougt) is
accelleration and decelleration of current


I recognize this as a commonplace expression in this group (not unique
to you by any means). It is one of the most ill-conceived statements
ever to come down the pike and your conundrum (as for others) in
trying to retrofit it into a theory is part and parcel to its poor
analogy.

I need it explained
in every day language


Hi Art,

The plain, every day language of budgets is there. If you cannot
balance that simple ledger, then you have scant chance of
understanding the larger enigma.

73's
Richard Clark, KB7QHC
  #3   Report Post  
Old August 17th 04, 04:36 AM
Cecil Moore
 
Posts: n/a
Default

wrote:
I suspect it has to do with relative phase angles but I need it explained
in every day language


Art, a single RF traveling-wave wire has a natural Z0 in the
ballpark of 600 ohms which sets the V/I (E/H field) ratio.
The feedpoint current and the current at any point on a
standing-wave antenna is the phasor sum of the forward current
and the reflected current. Vf/If and Vr/Ir remain in the
ballpark of 600 ohms but Vf+Vr and If+Ir vary up and down
the wire. The current is high at a 1/2WL dipole feedpoint
because If and Ir are in phase at that point. The current is
low at a 1WL dipole feedpoint because If and Ir are out of
phase at that point. But If is approximately the same for
both antennas and Ir is approximately the same for both antennas.

That's why the superposed If+Ir at the bottom of a loading
coil is not usually equal to the superposed If+Ir at the
top of a loading coil. Each of the two currents indeed has
close to a constant magnitude through the coil but the phases
of If and Ir are changing in opposite directions. Thus their
sums are different except for the special case where the
relative phase difference is equal at both ends of the coil.

But for understanding RF radiation, If is fairly constant
and Ir is fairly constant, and each of those currents cause
radiation. Thinking about a terminated Rhombic Vs an unterminated
Rhombic will separate the two processes out in your mind.
--
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! =-----
Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Transmission line radiation Ron Antenna 16 April 26th 04 01:03 AM
Cardiod radiation pattern - 70 cm phased vertical dipoles Ray Gaschk Antenna 3 February 21st 04 12:26 AM
Radiation Resistance & Efficiency Reg Edwards Antenna 23 January 10th 04 11:56 AM
Incoming radiation angles Art Unwin KB9MZ Antenna 33 January 5th 04 11:11 PM
Measuring radiation resistance Reg Edwards Antenna 11 December 13th 03 12:51 PM


All times are GMT +1. The time now is 03:56 PM.

Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright ©2004-2025 RadioBanter.
The comments are property of their posters.
 

About Us

"It's about Radio"

 

Copyright © 2017