Copper Talk » Ask The Tech » Antennas » A question about radiating elements? « Previous Next »

Author Message
Top of pagePrevious messageNext messageBottom of page Link to this message

Marconi
Advanced Member
Username: Marconi

Post Number: 791
Registered: 11-2001


Posted on Monday, August 18, 2008 - 7:03 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have a question. I see it written and discussed that a J-Pole does not radiate from the bottom 1/4 wave element because of an antenna rule that states: two elements that are close and parallel with equal current magnitude and opposite phase will show cancellation of RF.

If true, what would happen if there were 4 - 1/4 wave elements surrounding the radiator (like the Sigma IV) instead of only one like in the J-Pole?
Top of pagePrevious messageNext messageBottom of page Link to this message

Tech237
Moderator
Username: Tech237

Post Number: 1052
Registered: 4-2004
Posted on Monday, August 18, 2008 - 7:50 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

It still would not radiate from the bottom quarter wave, as the current on the shield of teh coax, which is the side connected to those stubs would now be equally split across all the stubs.
Simon
Tech237
N7AUS

Add Your Message Here
Post:
Username: Posting Information:
This is a private posting area. Only registered users and moderators may post messages here.
Password:
Options: Enable HTML code in message
Automatically activate URLs in message
Action: