fisher gold bug metal detector

[Unregistered]

Hi to all
I have got a fisher detector which deosn`t go deep very much,I would like to get some advise on how I can make it go deeper,adding to voltage or ampers,or adding some kind of amplyfier to the itscircuit,or if the last solution is more turns in the coil socan you tell me how many turns and what size wire? will be any harm to device when I connect it?
You can email me on; tajpoury @ekit.com


thanks fash

[kt315]

hi

some points we must begin to view.

1. all brands have VLF sch. with PARALLEL resonance V type TX contour (PRC).
2. GROZA-III (THUNDERBOLT-III) is NOR PRC type of VLF.
3. GROZA-III have theoretically UNLIMITED CURRENT of PUMPING.
4. we can see - GROZA has J SERIAL resonance J type TX contour (SPC).

resume. you can increase the diameter of a coil.

YOURS

[Unregistered]

fisher gold bug metal detector

Hi

I not a specialist I don`t undrestand the four item above,can any one explain
them,please.I really like to know what they mean.

thanks

[Largesarge]

Nope, but I can give you idea of how to proceed. First you're going to have to find out the inductance of the Gold Bug coil to be able to match it with your new coil. Then go to www.chemelec.com and click on his Java script calaculators, then scroll down to the last inductance calculator (revised Aug. 03) and start plug'n in the numbers. The first number is the desired ind. (for microhenries put a decimal point in front. For wire guage I's use 22, the diameter, well I think we know what that is going to be. As for coil length I use .25", that seems to work out pretty good.


There are several posts in the coil section of the forum that will give good how-to's on winding a coil, give a look-see, good luck and happy and deep hunting.

[Rattlesnake Jim]

No depth on the fisher Gold Bug??????

Hello Fash!
Before you go to a lot of trouble for nothing I would get the service manual for the Gold Bug from Fisher or just send it to them for a tune up. The Gold Bug has special tuned circuits that could be out of whack. There is a certain way to tune the circuits for max performance with the coil. I have the manual and have worked on the Gold Bugs for years. I've even built custom underwater models.
A common problem was owners who would try to tweek the pots inside to get more depth and usually got the circuits so far out that they would barely work at all.
Best wishes.
RSJ

[Largesarge]

Very good point Jim, I thought the GB was a pretty decent machine. If you don't know what you're do'n inside that box, don't go there.

[Unregistered]

gold bug

Hi
Thanks for your attention ,I really don`t know what is inside the gold bug and how to tune it.

If I knew what potansiometer is for what job then I could do some tuneing on it.

I can not send it for tuning because it is illigal in this country to have metal detector.

Another problem is that GB is very sensetive to small metal pieses(minerals) in soil ,do you have any solution for this?


I still got no explaination for above terms "GROZA" , "TUNDER BULT" and other words written by kt315,...


GB deosn`t have any kind of discrimination and dept reading capability ,question is ,is there any circuit or kit seperatly availiable to add to it to make it able for discrimination and dept reading.


[email protected]

thanks
Fash

[Rattlesnake Jim]

Fash, the Gold Bug was designed to find small bits of metal. All metals, but to tune out the ground minerals. As far as I know there is no easy way to add discrimination or depth reading. The circuits would have to be completely redesigned. I'd learn to use it as it was designed and just get used to digging a lot of junk. You will find a lot of goodies mixed in with the junk that other detectors would miss anyway.
You said it was sensitive to the minerals in the ground. You must use the ground balance to tune them out. I would start by using the autotune mode. Set the threshold so that you barely hear it humming.( That's the knob on the back near where the coil cable connects.) set the sensitivity to 5 or 6, and the ground balance midway. With the coil a foot above the ground you lower it toward the ground fairly fast. If the threshold gets louder as you get near the ground you must turn the ground balance knob counter clockwise slightly and try again. Only listen to what happens as the coil goes down toward the ground, not what it does when you lift it away from the ground. If it goes silent approaching the ground then turn the ground balance knob clockwise slightly.
You have to tune the ground balance until the detector doesn't see the ground at all. (No change in the threshold.) When you are ground balanced then the detector will work properly.
Best wishes!
RSJ

[Ed in SoDak]

Very good point Jim, I thought the GB was a pretty decent machine. If you don't know what you're do'n inside that box, don't go there.

I have to agree also. The makers used expensive test equipment to adjust all those parts. How can anyone who is not an expert in the method and also owing the proper tools make adjustments that are better?

If all the manufacturer had to do was turn a few trimmers and make his detector better, wouldn't he do just that before selling it? It costs more money to install adjustable parts instead of fixed, non-adjustable types. Why would they include the more expensive parts, and then not set them for peak performance in every individual machine? The concept that we on the street can do it better is a myth. Still, it's only natural to assume it, if the machine does not seem to perform properly.

If it does need adjusting or replacement of parts, the best method is to use the same equipment as was used originally and perform the same steps in the exact same order.

If you have a problem and there is no other recourse, you can mark the screws precise position before you begin and turn them slightly one at a time, then test, and count turns and make a written list of all of this so you can return to original settings. Still, this will only be set for your workbench or where you perform the work, unless you give the machine a complete test after every slight change to see if it is improved or worsened.

Many settings are inter-related. Changing one here will affect another over there, in a different way you may not notice till you find it no longer works at all.

According to Fisher, who makes this machine, any circuitry that related to discerning or rejecting one metal over another was intentionally left out. It would take an electrical engineer to redesign them back in. It it not so simple as adding a little part here or turning a knob there.

Be careful, as a broken detector to you is the same as no detector at all.

There are other coils you might buy, but we'll assume there is no store that would sell them where you are located.

Coils are as particular as the rest. Any change in diameter, shape, size of wire, construction, relationship between the two or more coils, and you must adjust them as a whole to work with the control box. Larger coils will seek more deeply, but will not center on the target as well and will also see any nearby trash and sit upon a greater amount of soil that may be mineralized. So, nothing is perfect in detectors. Far from it.

They look very simple, but you are working with ripples in a pond. Move any stone in the pond, the ripples will change throughout the whole pond. I hope you are a very patient man!

The Gold Bug gets excellent depth, but yes, it will only find metal and is equally as sensitive to iron as it is to aluminum foil or gold.

Find a sample of what you seek. Place this on the ground in the area you wish to hunt. Now, use the controls on the outside of the detector to set it to respond in the strongest fashion. Use new, strong batteries. Unless you can obtain a different detector with discrimination built-in, this is the best you can hope for in your circumstances.

Good luck!
-Ed

[Unregistered]

fisher

[QUOTE=kt315]some points we must begin to view.

1. all brands have VLF sch. with PARALLEL resonance V type TX contour (PRC).
2. GROZA-III (THUNDERBOLT-III) is NOR PRC type of VLF.
3. GROZA-III have theoretically UNLIMITED CURRENT of PUMPING.
4. we can see - GROZA has J SERIAL resonance J type TX contour (SPC).

[Unregistered]

some points we must begin to view.

1. all brands have VLF sch. with PARALLEL resonance V type TX contour (PRC).
2. GROZA-III (THUNDERBOLT-III) is NOR PRC type of VLF.
3. GROZA-III have theoretically UNLIMITED CURRENT of PUMPING.
4. we can see - GROZA has J SERIAL resonance J type TX contour (SPC).

resume. you can increase the diameter of a coil.

YOURS

Hi
I thanks for your answers but can you please explain what above specialised words means in easy english .


Thanks
fash

[Unregistered]

fash, the post below is nonsense. It doesn't mean anything to anyone except the yoyo or bozo that wrote it. It has no technical merit. It means nothing!

"Originally Posted by kt315
some points we must begin to view.

1. all brands have VLF sch. with PARALLEL resonance V type TX contour (PRC).
2. GROZA-III (THUNDERBOLT-III) is NOR PRC type of VLF.
3. GROZA-III have theoretically UNLIMITED CURRENT of PUMPING.
4. we can see - GROZA has J SERIAL resonance J type TX contour (SPC).

resume. you can increase the diameter of a coil.

YOURS"

[Ed in SoDak]

Sounds like he's peddling his godzilla detector which samples the inverse of the transmitted signal in the coil, and thus the signal can be made stronger. Just my guess!

-Ed

[Unregistered]

Hello Fash!
Before you go to a lot of trouble for nothing I would get the service manual for the Gold Bug from Fisher or just send it to them for a tune up. The Gold Bug has special tuned circuits that could be out of whack. There is a certain way to tune the circuits for max performance with the coil. I have the manual and have worked on the Gold Bugs for years. I've even built custom underwater models.
A common problem was owners who would try to tweek the pots inside to get more depth and usually got the circuits so far out that they would barely work at all.
Best wishes.
RSJ

Dear RSJ

I have seen one manual on internet it doesn`t talk about tuning the metal detector.
What about your manual ?Deos it talk about tunings?

thanks
fash