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Old November 11th 15, 11:59 AM posted to rec.radio.amateur.antenna
amdx[_3_] amdx[_3_] is offline
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First recorded activity by RadioBanter: Aug 2013
Posts: 154
Default Flex dryer vent hose loop antenna

On 11/10/2015 2:36 PM, rickman wrote:
On 11/10/2015 12:40 PM, amdx wrote:

When transmitting with a 96%
efficiency, using silver plating will only improve this to 96.2% at
very best. Not really useful and likely not measurable. Better to deal
with the significant losses like the extremely bad connection between
the vacuum variable cap and the loop. Straps???!!! Get real!


Where did you get 96% efficient?

From the site below.
"The efficiency of a magnetic loop antenna is typically calculated as
(Smith, 2006);

efficiency=Rr/(Rr+Rhf2)

Rr=radiation resistance (ohms)

Rhf2=RF losses from combined skin effect and proximity effect (ohms)

This term is not adjusted for the effects of ground or nearby objects."


This builder has a different design.

http://gridtoys.com/glen/loop/loop3.html


You'll enjoy this line on his page.

"*Aluminum works well in magnetic loop antennas. Yes, pure copper is a
little better, but in multiple conductor magnetic loop antennas, there
may be difficulty getting a copper loop to support its own weight.
Structurally, aluminum is a lot better. Just make the conductors bigger."

Mikek