loss resistance of a small loop antenna - RF Cafe Forums

The original RF Cafe Forums were shut down in late 2012 due to maintenance issues - primarily having to spend time purging garbage posts from the board. At some point I might start the RF Cafe Forums again if the phpBB software gets better at filtering spam.

Below are the old forum threads, including responses to the original posts.
-- Amateur Radio
-- Anecdotes, Gripes & Humor
-- Antennas
-- CAE, CAD, & Software
-- Circuits & Components
-- Employment & Interviews
 -- Miscellany
-- Swap Shop
-- Systems
-- Test & Measurement
-- Webmaster

Whitebird
Post subject: loss resistance of a small loop antenna
Posted: Sun Feb 19, 2006 7:47 pm
 
Captain

Joined: Tue Dec 27, 2005 1:51 pm
Posts: 8
Hi!

What is the formula to calculate the loss resistance of a small loop antenna having a square shape?
 
 
nubbage
Post subject: Loss Resistance of small loop antennas
Posted: Thu Feb 23, 2006 8:03 am
 
General
User avatar

Joined: Fri Feb 17, 2006 12:07 pm
Posts: 218
Location: London UK
The formula I have is for circular loops, but I understand the important quantity is the perimeter, not the shape.

For a copper wire antenna

Loss Resistance is = 0.000996*SQRT(F)*perimeter/diameter of wire

all dimensions in meters and MHz


nubbage
 
 
nubbage
Post subject: Loss resistance of a loop antenna
Posted: Thu Feb 23, 2006 8:43 am
 
General
User avatar

Joined: Fri Feb 17, 2006 12:07 pm
Posts: 218
Location: London UK
Caramba

Wrong again. The perimeter and radius should be in feet and inches respectively in the previous posting

nubbage
 
 
Whitebird
Post subject:
Posted: Thu Feb 23, 2006 2:36 pm
 
Captain

Joined: Tue Dec 27, 2005 1:51 pm
Posts: 8
OK, thank you very much
 
 
Whitebird
Post subject:
Posted: Sun Feb 26, 2006 2:39 pm
 
Captain

Joined: Tue Dec 27, 2005 1:51 pm
Posts: 8
And now what is the inductance of a square small loop made of copper wire?
 
 
fred47
Post subject: Inductance of a square loop
Posted: Thu Mar 23, 2006 8:46 pm
 
General
User avatar

Joined: Wed Feb 22, 2006 3:51 pm
Posts: 104
Hi!

See the book Inductance Calculations by Grover - available through Amazon (surprise!).

Good Luck!
fred
 
 
RFdumm
Post subject: Re: loss resistance of a small loop antenna
Posted: Sun May 14, 2006 11:55 pm
 
Lieutenant

Joined: Mon Apr 24, 2006 10:27 pm
Posts: 1
Whitebird wrote:
Hi!

What is the formula to calculate the loss resistance of a small loop antenna having a square shape?


this can be helpful
http://ww1.microchip.com/downloads/en/A ... 00831b.pdf



Posted  11/12/2012