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Old June 26th 08, 06:35 PM posted to rec.radio.amateur.antenna
John KD5YI[_3_] John KD5YI[_3_] is offline
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First recorded activity by RadioBanter: Jun 2008
Posts: 24
Default Transmission line choke - Richard Clark


"John Ferrell" wrote in message
...
On Wed, 25 Jun 2008 16:17:18 GMT, "John KD5YI"
wrote:

In another thread, Richard said:

"You can achieve astonishingly high Zs with a coiled
transmission line with very little effort (roughly 8-12 turns on a
liter pop bottle - empty of course - for HF)."

The key is "...empty of course...". What if one were to fill the bottle
with
relatively pure water to keep dissipation factor low? Water's dielectric
constant is about 80. This would increase the stray capacitance, thus
reducing the required turns to achieve resonance. Would this increase the
Q
due to lower loss in the inductance?

Just curious.

John

***GASP!***
Did you just invent a water-tuned variable inductor?

John Ferrell W8CCW
Beware of the dopeler effect (pronounced dope-ler).
That's where bad ideas seem good if they come at you
fast enough.



Well, yeah - unintentionally, I guess. See my reply to Tom.

John