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#1
12-26-2011, 09:47 PM
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Which devices are you speaking about? Static LRL or geomagnetic LRL sensor?
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Global capital is ruining your life? You have right to self-defence! 
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#2
12-26-2011, 10:46 PM
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And many wood LRL boxes also have paint or varnish on the inside. But it is true, water vapor is a gas which can penetrate through small pores in the paint to enter the wood fibers and increase the humidity. The increase in humidity will cause most wood fibers to expand a small amount to make small changes in the box dimensions, and can even cause the box to warp to slightly non-rectangular. This happens when one side of the box is warm from the sun to drive away the humidity, and the other side is cooler to conserve the humidity in the fibers. I would expect the only serious problem is when high impedance parts of a circuit are in contact with the wood or other partially conductive parts of the box. Maybe this is part of the reason why we see several people who build the same project find different performance. For the parts of a circuit which are lower impedance, I do not think there will be so much problem with circuit malfunctions due to leakage paths. But there are definitely consequences for absorbing electromagnetic waves that could be significant at some frequencies and power levels. It seems that it would depend on what kind of energy the transmitter is expected to pass through the box, and what kind of energy a receiver is expected to receive through the walls of the box. I would think that it is important to consider what kind of signals you are sending and receiving in order to choose a good box material. In some applications, maybe a metal box is best, but others may be better with plastic or wood fiber based enclosures. A varnished cardboard box could even work if the material is strong enough. Maybe a teflon box will have some use for special applications because it has good insulating properties, and does not pass moisture. Best wishes,  J_P
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#3
12-27-2011, 01:09 AM
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Another idea for LRL experimenters to think of is the variations that wood can make for some electrical circuits. When we are working with electrostatics, and with small electromagnetic signals, the conductivity of a wood box can work to cause anomalies in the air, or to block certain electrostatic fields. The same conductivity that we find with wood during high humidity can cause electromagnetic waves to become polarized because the electric component of a wave is shorted in the plane of the wood surface.
This can happen any time the wood has become conductive because of absorbing moisture, or for other reasons such as conductive paint. (Metal flake paint can have some degree of conductivity, and black paint with carbon pigment can be partially conductive). If an electromagnetic wave becomes polarized, then the reception of this wave will be altered so it is not received in the same way as when the conductive wood is not present. Of course, a metal box will have the same effect, and maybe stronger. Metal boxes are capable of completely blocking some kinds of signals. But here is where we can find a problem: If we have a wood box that can absorb moisture to become more wet or dry depending on the humidity and the temperature, then the conductivity of the wood can change to cause changes in the circuit performance which vary with the weather. This means the wood box can be the cause of a circuit to perform well in some weather conditions, then perform bad in other weather conditions. If the conductivity of the wood is causing variations in the circuit performance, this could deceive the LRL user to believe that the weather is acting on the soil, or on the atmospheric electric charges, when the poor performance is really caused by the wood box. One way to test to see if the wood box is a problem is to change from wood to plastic during weather when the performance is bad. Then see if there is any improvement in performance. If we see bad performance in wood, then improvement in plastic, we know the box is part of the problem. Then when the weather is very warm and dry, we can change back to wood to see if the performance changes. If the performance does not change when you are using wood in warm, dry weather, then it will confirm the wood was causing a problem only when the weather was damp. In warm dry weather, the wood should work similar to plastic, But wood should perform more like a metal box when the humidity is high. For electrostatic circuits, a wood box may be a good thing because it will not easily collect a static charge. But be careful to keep the antenna circuits separated so they do not touch the wood. We should remember that any RF that is broadcast from the box will be following near-field broadcast dynamics which are noticeably different than RF which has traveled many Km distance from a transmitter. You can expect a 90 degree phase angle in the RF that you send out, and if the supports for the broadcasting coil or the box behind it is partially conductive, then you can expect some of the wave to become polarized. We also expect the wave to become polarized vertically in the region where the wave penetrates the ground, if the ground is conductive. Take a close look at some of the commercial LRLs. The materials near the broadcasting and receiving coils are intentionally made to be iron or hard-pressed wood fiber or circuit board materials. This was done for a reason. When we see many different construction methods for experimental LRLs, I am not surprised to see people reporting different performance from the same circuit designs. The circuit design is only one part of the locator. The Tx and Rx antennas are another part which will perform much differently if they are not built and arranged the same. Best wishes, J_P
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#4
12-27-2011, 02:48 AM
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Metal box better
I have tried both. The metal box I find is better. The metal blocks extraneous radiation and protects the circuit which is sensitive to electrostatics. You can also put the base of the ES circuit, the ground, outside the box using it as an antenna ground plane. then make the antenna the collector for the ES.
Goldfinder
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#5
12-27-2011, 03:37 AM
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It sound like you are using an electrostatic detector. In this case, the materials and construction methods are very important. It seems very few people have anything more than a basic idea of how electrostatics work in real world conditions. With electrostatics we are working with electric fields that are basically static, capacitive signals, or could have some dynamic components which cause an anomaly where you hunt for treasure. But if you put the same electrostatic circuit in several different enclosures with different antenna designs, you will find each of them responds differently to electric field anomalies. I would also think that an electrostatic detector would work better with a metal box. However, if it is a modified detector which uses an RF tuner, then the tiny RF anomalies will be strongly influenced by different box materials. More importantly, the receiver antenna design will be more important than an electrostatic detector antenna is. For an VLF tuner, the enclosure and the materials near the coil will have a lot to do with the performance of the coil. Even passive conductors nearby will influence the reception of signals. I would think in the cases of VLF receivers and transmitters, the antennas are best kept separated from the rest of the circuitry, much as we see in commercial radio installations where the transmitter parts are kept away from the antenna where possible. We also see in some of the portable hand-held commercial transceivers that there are parts of the circuit which are shielded with metal foils to keep external energies from interfering with small signals. Often we see even transceivers that are in metal boxes, which helps to keep stray energies from causing interference in the circuits. But in the case of treasure locator LRLs, there may be times when the designer wants stray signals to impinge on the circuits inside the box. However, I doubt any LRL experimenters will take these precautions except for a few who have some idea of how these signals work. Best wishes, J_P
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#6
12-27-2011, 06:14 AM
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Original Alonso's PD has wooden box and plastic coil housing. Yellow and red PD are all wooden. Mineoro PDc and FG are wooden. Mineoro DCH has metalic box and plastic coil housing. Etc......
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Geo
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#8
12-27-2011, 12:27 PM
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Unstable circuits and lots of external noise is excellent. Also internal noise from transistors and resistors is good too. If possible, make sure you have a lot of loose internal wires connected to the high impedance circuits. It helps if these loose wires bounce around and move while you are carrying the pistol through the treasure hunting field. They can help you to cause beeps to come in locations where you normally would not detect anything. Finally, don't forget to rub some of the substance that gold DNA produces on the circuit board -- it probably won't work unless you do.  Best wishes, J_P
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