View Single Post
  #16   Report Post  
Old November 3rd 15, 07:14 PM posted to rec.radio.amateur.antenna
amdx[_3_] amdx[_3_] is offline
external usenet poster
 
First recorded activity by RadioBanter: Aug 2013
Posts: 154
Default Flex dryer vent hose loop antenna

On 11/2/2015 6:39 PM, Jeff Liebermann wrote:
On Mon, 2 Nov 2015 09:13:38 -0600, amdx wrote:

Below some pressure level, it will probably flop over if mounted
vertically. That's why I mumbled that I wasn't sure if it should be
mounted vertically with a support pole, or horizontally on a flat
sheet of plywood. Both will work, but I'm not sure which is better.


Hang it upside down.
Mikek


But, all the photons will fall out of the loop that way.

Actually, there's a problem. It doesn't work as well upside down.
The magnetic loop has a rather directional field and takeoff angle and
does NOT have a constant current around the loop:
http://www.nonstopsystems.com/radio/vids-ant/antenna-Mag-Loop-Demo1.wmv
https://www.youtube.com/watch?v=SUYI81dkEMA

I suspect that an inverted loop will send most of the RF into the
ground. I should probably test this.
http://www.nonstopsystems.com/radio/img-ant/antenna-magloop-rad-angle.gif

You might find this interesting on designing the 50 ohm matching
network to the loop, where the impedance varies by where it's fed:
http://www.g0cwt.co.uk/magloops/new_page_6.htm



Sorry Jeff, When my post didn't show up, I noticed I sent it to you.
Here it is for the rest.



Just to add to the confusion,
Helically Loaded


You might glean info from here, or at the least

admire all the work put into the projects.



http://theradioboard.com/rb/viewtopic.php?f=10&t=4399


Copper doughnut with lots of solder connections
http://www.aa5tb.com/jl1boh_03.jpg


http://www.hlmagneticloopantennas.com/

Hmm, I read a few comments, maybe not the way to go.



Mikek