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PostPosted: 25 Nov 2015, 08:13 
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A loop antenna crystal radio is of interest, on account of its portability, though it is no match for a crystal radio using an external vertical wire antenna and earth.

If it's performance could be considerably improved with increased loop size, then its portability would be the first casualty.

As usual 2 configurations are possible - parallel-tuned-series-fed and series-tuned-shunt-fed.

1. Parallel-tuned-series-fed version

Read more at

http://nandusthoughts.blogspot.in/2015/ ... radio.html

Regards,

Nandu.


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PostPosted: 09 Dec 2015, 18:45 
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Can we have a schematic of this. I can't quite picture it. and 4 turns on the secondary does sound much.

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PostPosted: 10 Dec 2015, 00:46 
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I did that with a LF loop once. Worked quite well! :D

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PostPosted: 10 Dec 2015, 00:50 
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mwhouston wrote:
Can we have a schematic of this. I can't quite picture it. and 4 turns on the secondary does sound much.


That should be doesn't send much.

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PostPosted: 10 Dec 2015, 06:04 
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Loop antennas are very sensitive to impedance mismatch.

My LF loop for example is 52 turns, 1M per side (4M per loop) and a 4-turn pickup coil for 50 ohms. Using any more turns destroys both the antenna "Q" factor and the null characteristics.

Cheers!

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PostPosted: 10 Dec 2015, 07:04 
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Geek wrote:
Loop antennas are very sensitive to impedance mismatch.

My LF loop for example is 52 turns, 1M per side (4M per loop) and a 4-turn pickup coil for 50 ohms. Using any more turns destroys both the antenna "Q" factor and the null characteristics.

Cheers!


Schematic?

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PostPosted: 10 Dec 2015, 13:19 
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http://geek.scorpiorising.ca/GeeK_ZonE/ ... pic=3929.0

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PostPosted: 10 Dec 2015, 17:16 
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Ok I get it now.

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PostPosted: 11 Dec 2015, 09:38 
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So sorry I was away, Houston.

Many thanks for making it so clear, Gregg.

Regards,

Nandu.

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