LinkBack Thread Tools Search this Thread Display Modes
Prev Previous Post   Next Post Next
  #14   Report Post  
Old February 23rd 06, 03:28 PM posted to rec.radio.amateur.antenna
Frank
 
Posts: n/a
Default nec simulation - unexpected result ??

"dansawyeror" wrote in message
...
All,

I have been experimenting with various loaded antennas to use in my
relatively limited space. For this I assumed the two arms of a dipole must
be identical to support resonance, this assumption has not been supported
by modeling.

Actual model runs show that if the two arms of a dipole are close then
there is sufficient interaction that they will combine to form a single
resonance. The model below shows a simple example of this. The loads and
length of the arms are not equal, however nec predicts a single resonance
at about 3.5 MHz. Changes of 10 to 20 percent around resonance seem to
create one resonance.

Is there an explanation for this?

Thanks - Dan kb0qil


No matter what Dan, you should see only one resonance at the overall length
of a half wave. Not that resonance has any bearing on antenna efficiency.

Also; your NEC model has uneven segmentation, which does produce significant
errors. Interesting to note that your antenna is also resonant at 7 MHz.

73,

Frank


 
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
Info - Icom IC-R75 with Kiwa Mods and Antenna Supermarket Eavesdropper SWL Sloper RHF Shortwave 12 December 25th 05 12:25 AM
Loading Coil Q Buck Antenna 16 March 25th 05 08:07 PM
Current in loading coil, EZNEC - helix Yuri Blanarovich Antenna 334 November 9th 04 05:45 PM
The "TRICK" to TV 'type' Coax Cable [Shielded] SWL Loop Antennas {RHF} RHF Antenna 27 November 3rd 04 01:38 PM
The "TRICK" to TV 'type' Coax Cable [Shielded] SWL Loop Antennas {RHF} RHF Shortwave 23 November 3rd 04 01:38 PM


All times are GMT +1. The time now is 05:52 AM.

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