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#2
12-11-2011, 05:03 PM
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Quote:
 Hi Jack, you try very stabil XR2206 for sinusoidal wave generator plus Amplifier.
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#3
12-11-2011, 06:56 PM
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waht wave you need square sinoudeal triangle?
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#4
12-12-2011, 01:59 PM
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HI TO ALL
I found a transmitter VLF.But no list of parts 1-How telescopic antenna to replace the coils in the circuit? 2-Do more with telescopic antenna beam waves? 3-It was the middle of the coil and it was attached to the telescopic antenna? A general question: 4-Waves in the ground after colliding with the metal to be reflected in what form? 1 to 3 questions please help me?
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#5
12-12-2011, 03:02 PM
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Quote:
They use a very large loop which is placed on the ground in a circle around the area where they will search. At 30 KHz the geologist expects to penetrate at least 10 meters into the ground. But when he adjusts the frequency to lower, he can expect to penetrate to 25 meters or more at 10-12 KHz. Is this how deep you want to locate things? A geologist locates things because he knows what is the geology of the area, and he knows what kind of rock formations are expected to be buried under the soil. He also knows that different rocks and soil will absorb different amount of VLF energy. He can then walk around inside the loop he put on the ground while carrying a VLF receiver loop to find the how strong is the signal at different locations. He makes a survey inside the loop which he places on the ground until he has a map of how strong the signal strength is for different locations. Sometimes he looks for VLF null angles and other data for the reception of the VLF signal at different locations inside the transmitter loop. When he is done making his survey, he takes the data back to his office and compares it with other maps he has for the same area which show other surveys, such as magnetometer, ground resistivity, MMI, induced polarization, etc. By using his knowledge of geology and the survey data, he can make a map of where he believes different rock formations and ore formations are located. Then he marks his maps for places to dig for ores such as gold, silver, copper, palladium, etc. There is no part of his VLF survey equipment which uses a telescoping antenna to locate things under the ground. A telescoping antenna is almost never used for a hand-held VLF transmitter. A portable VLF transmitter usually uses a loop antenna. A geologist is not looking for VLF waves to reflect from buried rings or coins. He is looking to measure how much of the VLF energy is absorbed into the ground from different locations on the surface. A geologist prefers to use the VLF signal from a government operated transmitter if there is one present within 1000 Km that has a strong enough signal for him to use. Then he does not need to set up his own transmitter and put a long cable on the ground to make a loop around the area that he wants to survey. In the USA and Canada geologists often tune their VLF receiver to use the signal which is transmitted from Annapolis, Maryland (21.4 kHz), Cutler Maine, 24.0 kHz) and Seattle, Washington (24.8 kHz). There are other VLF transmitters located around the world which are used by geologists in other countries. It is helpful to learn basic electronics and radio wave propagation theory before you build a transmitter. You should be careful to learn the laws in your country so you know what is the maximum amount of radiated power you are permitted to broadcast and what frequencies. You should also use the correct instruments to take measurements that insure you are operating your transmitter within the law. See below for location of some government-operated VLF transmitters and the range where they are used for surveys to locate things under the ground. (Some of these stations may not be currently in operation, and new transmitters may have begun operating since the time of this map). Best wishes, J_P
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#7
12-12-2011, 05:45 PM
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Quote:
Hi jack Help for you, ic is 4046 PLL . for transistors ,you can use BD sires
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#9
05-26-2012, 11:15 AM
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Quote:
__________________
Global capital is ruining your life? You have right to self-defence!
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transmitter vlf
Hybrid Mode
