Find's Treasure Forums
Welcome to Find's Treasure Forums, Guests!
You are viewing this forums as a guest which limits you to read only status.
Only registered members may post stories, questions, classifieds, reply to other posts, contact other members using built in messaging and use many other features found on these forums.
Why not register and join us today? It's free! (We don't share your email addresses with anyone.) We keep email addresses of our users to protect them and others from bad people posting things they shouldn't.
Click here to register!
Need Support Help?
Cannot log in?, click here to have new password emailed to you
Changed email? Forgot to update your account with new email address? Need assistance with something else?, click here to go to Find's Support Form and fill out the form.
Ground balancing with ferrite
- Thread starter GunnarMN
- Start date
BarberBill
New member
I see no point as long as the detector has manual ground balance. Balancing to the soil at the hunt site seems a better choice to me.
BB
BB
I've posted this, with George's permission, several times in the past, but it's relevant to this thread so I'll post it again. For those who don't know, George discovered the phase shift principle that allows ground balancing, and he designed the first detectors with manual, auto and preset ground balance.
A pure ground is a soil condition that reacts like it was pure ferrite. In other words a perfect magnetic condition where no electrical conduction (eddy currents) takes place. We can think of this as a soil that produces a signal in the detector with zero phase shift relative to the transmitted signal. This is considered our reference signal of zero phase to which all other signals can be referenced to. Of course the only real life object that produces this type of signal is pure ferrite. So ferrite becomes our reference target and produces what we call a pure "X" reactive signal. Of course real ground conditions do not behave like pure ferrite. When subjected to a detectors magnetic field small currents begin to flow in the soil. This will cause the soil signal to be displaced slightly from that of pure ferrite. We call this difference a phase shift and define it to have an angle in degrees negative relative to pure ferrite. In addition, this phase shift produces a new signal in the detector which we call the "R" component signal. We can carry this analysis one more step. Using Trigonometry the ratio of the X signal to the R signal can be shown to be the actual measured phase of the ground. All grounds have varying amounts of magnetic and conductive properties. Therefore, the ratio of the X or magnetic signal and R, the conductive signal, will vary from one location to another. However, the phase produced by this characteristic will always be negative relative to zero which is the phase of pure ferrite.
Manual ground adjustment works in this manner: When you position the Ground Adjust control to the phase of the target, in this case the ground, any up or down motion of the coil does not produce a corresponding change in the audio volume. For example, when you position the control to zero phase, and then move a piece of ferrite around near the coil, the audio volume will not change. In other words you have balanced out to the ferrite. However, if you now lower the coil to real ground the audio will increase in volume. Of course this indicates that you are not balanced to the ground
For fixed, or preset, ground balanced machines the phase error between the internal preset balance and the actual ground condition can be much more than slight. The internal preset is calibrated for +0.5 degrees. This is in an area where a real ground phase never occurs. The actual ground phase may be -2 or -3 degrees negative. That
A pure ground is a soil condition that reacts like it was pure ferrite. In other words a perfect magnetic condition where no electrical conduction (eddy currents) takes place. We can think of this as a soil that produces a signal in the detector with zero phase shift relative to the transmitted signal. This is considered our reference signal of zero phase to which all other signals can be referenced to. Of course the only real life object that produces this type of signal is pure ferrite. So ferrite becomes our reference target and produces what we call a pure "X" reactive signal. Of course real ground conditions do not behave like pure ferrite. When subjected to a detectors magnetic field small currents begin to flow in the soil. This will cause the soil signal to be displaced slightly from that of pure ferrite. We call this difference a phase shift and define it to have an angle in degrees negative relative to pure ferrite. In addition, this phase shift produces a new signal in the detector which we call the "R" component signal. We can carry this analysis one more step. Using Trigonometry the ratio of the X signal to the R signal can be shown to be the actual measured phase of the ground. All grounds have varying amounts of magnetic and conductive properties. Therefore, the ratio of the X or magnetic signal and R, the conductive signal, will vary from one location to another. However, the phase produced by this characteristic will always be negative relative to zero which is the phase of pure ferrite.
Manual ground adjustment works in this manner: When you position the Ground Adjust control to the phase of the target, in this case the ground, any up or down motion of the coil does not produce a corresponding change in the audio volume. For example, when you position the control to zero phase, and then move a piece of ferrite around near the coil, the audio volume will not change. In other words you have balanced out to the ferrite. However, if you now lower the coil to real ground the audio will increase in volume. Of course this indicates that you are not balanced to the ground
For fixed, or preset, ground balanced machines the phase error between the internal preset balance and the actual ground condition can be much more than slight. The internal preset is calibrated for +0.5 degrees. This is in an area where a real ground phase never occurs. The actual ground phase may be -2 or -3 degrees negative. That
Ed in SoDak
Member
Ferrite is used in the black bar or rod in an AM radio. It's also in the plastic lump you see wrapped around the power cords and cables used on computers and other electronic devices, in case you have more old computer cables that you don't mind chopping up than AM radios.
What George was saying is the ferrite is used to find the zero reference, really nothing more. In order to know and accurately measure the amount of phase shift of the ground, you need to know how far above or below some reference. You do not actually set your detector to a piece of ferrite, that's essentially the same as turning ground balance off.
It's kind of like the old electrical meter that had a moving pointer instead of the digital readout you see now. In order to accurately measure a voltage, the operator first had to make sure the pointer was resting on zero before making his measurements. If the needle where shifted off this zero reference, the reading indicated on the scale would be incorrect by that amount.
That's all, nothing more nor less. Ferrite has no use to the average detector user, unless he is adjusting the internal phase reference. He'd better know very well what he's doing to attempt that, if it's even available to adjust. You won't find it in a menu or on a knob of any typical machine.
It's all right there is this paragraph from George's article above:
"Manual ground adjustment works in this manner: When you position the Ground Adjust control to the phase of the target, in this case the ground, any up or down motion of the coil does not produce a corresponding change in the audio volume. For example, when you position the control to zero phase, and then move a piece of ferrite around near the coil, the audio volume will not change. In other words you have balanced out to the ferrite. However, if you now lower the coil to real ground the audio will increase in volume. Of course this indicates that you are not balanced to the ground."
As George state, you can skew your detector's externally adjustable GB to be quiet on a ferrite sample, but in so doing, you have set your machine's GB to a position that will be incorrect for just about any ground you detect on.
I ran some tests on this and in every case, adjusting to a piece of ferrite caused a loss of depth. I've read where some people believe this is how they need to adjust their detectors to look for meteorites, but I am sorry to report they are wrong. They may have still learned to accept the skewed signal and do find targets that way, but generally speaking, you hear the ground more and targets less.
-Ed
What George was saying is the ferrite is used to find the zero reference, really nothing more. In order to know and accurately measure the amount of phase shift of the ground, you need to know how far above or below some reference. You do not actually set your detector to a piece of ferrite, that's essentially the same as turning ground balance off.
It's kind of like the old electrical meter that had a moving pointer instead of the digital readout you see now. In order to accurately measure a voltage, the operator first had to make sure the pointer was resting on zero before making his measurements. If the needle where shifted off this zero reference, the reading indicated on the scale would be incorrect by that amount.
That's all, nothing more nor less. Ferrite has no use to the average detector user, unless he is adjusting the internal phase reference. He'd better know very well what he's doing to attempt that, if it's even available to adjust. You won't find it in a menu or on a knob of any typical machine.
It's all right there is this paragraph from George's article above:
"Manual ground adjustment works in this manner: When you position the Ground Adjust control to the phase of the target, in this case the ground, any up or down motion of the coil does not produce a corresponding change in the audio volume. For example, when you position the control to zero phase, and then move a piece of ferrite around near the coil, the audio volume will not change. In other words you have balanced out to the ferrite. However, if you now lower the coil to real ground the audio will increase in volume. Of course this indicates that you are not balanced to the ground."
As George state, you can skew your detector's externally adjustable GB to be quiet on a ferrite sample, but in so doing, you have set your machine's GB to a position that will be incorrect for just about any ground you detect on.
I ran some tests on this and in every case, adjusting to a piece of ferrite caused a loss of depth. I've read where some people believe this is how they need to adjust their detectors to look for meteorites, but I am sorry to report they are wrong. They may have still learned to accept the skewed signal and do find targets that way, but generally speaking, you hear the ground more and targets less.
-Ed