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Old 08-26-2013, 09:47 AM
Sebacid Sebacid is offline
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Join Date: Jul 2012
Posts: 18
Quote:
Originally Posted by wayne.ct View Post
OK, based on your suggestions and the calculations you have posted, I can visualize the transformer. It will be small enough to hold in one hand.

Here is what I have done so far:

I will be using 750 KHz as my center frequency as an example. This frequency is used by the famous WSB.

WSB is a 50,000 watt clear channel broadcasting station in Atlanta, GA.

The antenna is located in Tucker, GA according to Wikipedia.

Calculation #1

L = Total length of coiled wire

L = f/w = 299,792,458 (meter / second) / 2 * PI * 750,000 (/second)

= 299,792,458 / 2 * 3.14159 * 750,000 (meters) = 63.62 meters = 63.62 meters * .3048 ft / meter

= 19.39 feet

Calculation #2

L = Length of each turn = 19.39 feet / 20 = 0.9695 feet = 11.63 inches

Calculation #3

Circumference C = L; Diameter = Circumference / PI = 3.7 inches

H = Coil height = 0.2 * Diameter = 0.2 * (11.63 inches / PI)

= 0.74 inches

Calculation #4

Max diameter of wire. Space between strands of wire is 62 percent of wire diameter.

20 turns take 0.74 inches ===> 1 turn takes 0.74 inches / 20 = 0.037 inches

0.037 inches = 162 percent of wire diameter ===> 100 percent of wire diameter = 0.037 / 1.62

Wire diameter = 0.02286 inches (max.)

AWG 23 has a diameter of 0.0226 inches / 0.573 mm.

AWG 23 has resistance of 66.79 ohms / Km. which is 20.36 mOhms / ft.

For 19.39 ft, the coil will have 395 mOhms or 0.395 Ohms resistance.

I thought it would be larger than this. So much for my intuition.
There is a small mistake in your calculations...

L = Total length of coiled wire

L = f/w THIS IS WRONG, it should be c/w! (but you have calculated it correctly) = 299,792,458 (meter / second) / 2 * PI * 750,000 (/second)

= 299,792,458 / 2 * 3.14159 * 750,000 (meters) = 63.62 meters = 63.62 meters * .3048 ft / meter

= 19.39 feet
THIS IS WRONG!


If converted then 63,62 meters gives roughly about 209 feet (63,62x3,28=208,67).

That shouldn't fit in your hand anymore...

Remember you need two different setups, one wave, Hertzian, is the over ground wave, the other wave, Telluric, is the under ground wave. These two waves arrive at the point of reception in their own distinct time frames, giving rise to a difference in phase. Hence, multiple rings of interference patterns are produced. Since the Hertzian portion, over ground, time frame is based upon the velocity of light, then the Telluric portion, under ground, time frame gives the Telluric velocity. Two crystal sets, one over ground, one under ground, and a basic oscilloscope , that simple.

A great link for most information needed is provided in my first answer in this thread. Happy experimenting!

-Seb
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Last edited by Sebacid; 08-26-2013 at 07:37 PM.
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