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Old March 17th 06, 01:12 AM posted to rec.radio.amateur.antenna
Reg Edwards
 
Posts: n/a
Default Coils are transmission lines


Reg, would you care to share your formula for velocity factor?

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Cec, can't you find it in your bibles?

Velocity = 1 / Sqrt( L * C) metres per second

where L and C are henrys and farads per metre.

What you really want to know is how to calculate L and C from coil
dimensions. But you won't find that from any bible.

As a special favour, I'll attach the source code for the program to an
e-mail. Read it with a non-proportional text editor such as Notepad.

In your discussions on the other thread you have mentioned a coil's
self-resonant frequency. In the source code you will also find a
formula for Fself. Which, again, cannot be found in any bible. It is
a fairly straightforward 2 or 3-line formula.

Fself is not used anywhere in the program. It is available solely out
of interest. It is fairly accurate. I have measured it on many coils
of all proportions and numbers of turns from 1 inch to 6 feet long
with 1500 turns.
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Reg, G4FGQ