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Detector Technology and Electronics and new detectors => Detector Coils => Topic started by: Dontbstme on Thursday March 7 2019 01:39:38 AEDT AM



Title: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Thursday March 7 2019 01:39:38 AEDT AM
Hi folks.

My first big 30" CC for ML machines is up and running. It weighs 1043 grams and it's super stable. It works well in all coil settings - DD, Mono and Cancel.
It gets my 600 grams simulated gold nugget from Tin at about 51" in FP settings.
It is also relatively sensitive to small-ish nugs. It gets my Ozzy half gram gold at about 3" in the centre of the coil. I know smaller coils will get this much better, but this seems to be unusually high sensitivity to something so small compared to the coil size.

Any input regarding tests and settings will be appreciated.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: WM6 on Thursday March 7 2019 07:54:57 AEDT AM
1043 grams coil cable inclusive?

If so - good achievement.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Thursday March 7 2019 08:05:30 AEDT AM
  
1043 grams coil cable inclusive?

If so - good achievement.
Yes. 1043 grams for everything.
30"CC with the same Carbon shells for my MP is only 600 grams, but for PI the TX loop wire alone is 500 grams.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: mylab on Thursday March 7 2019 12:40:31 AEDT PM
  
Hi folks.

My first big 30" CC for ML machines is up and running. It weighs 1043 grams and it's super stable.
It works well in all coil settings - DD, Mono and Cancel.
It gets my 600 grams simulated gold nugget from Tin at about 51" in FP settings.
It is also relatively sensitive to small-ish nugs. It gets my Ozzy half gram gold at about 3" in the centre of the coil.

What GPX were you using, a 4500 or 5000, for the FP settings as the FP settings for either are different if using the soil/timing switch set to special. Therefore if on a 4500 the soil timing is sensitive/extra whereas on the 5000 it is fine /gold. If not in special then you were using either normal or enhance for either detector.Then of course there are the search modes of general deep & custom again with different FP settings for each.

So saying FP setting does not tell us much?

Also what coil setting?

And good on you if your CC coil works as good as you say on the GPX.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Thursday March 7 2019 15:09:26 AEDT PM
  
  
Hi folks.

My first big 30" CC for ML machines is up and running. It weighs 1043 grams and it's super stable.
It works well in all coil settings - DD, Mono and Cancel.
It gets my 600 grams simulated gold nugget from Tin at about 51" in FP settings.
It is also relatively sensitive to small-ish nugs. It gets my Ozzy half gram gold at about 3" in the centre of the coil.

What GPX were you using, a 4500 or 5000, for the FP settings as the FP settings for either are different if using the soil/timing switch set to special. Therefore if on a 4500 the soil timing is sensitive/extra whereas on the 5000 it is fine /gold. If not in special then you were using either normal or enhance for either detector.Then of course there are the search modes of general deep & custom again with different FP settings for each.

So saying FP setting does not tell us much?

Also what coil setting?

And good on you if your CC coil works as good as you say on the GPX.

I have 4500. The FP settings are in Normal mode. I tried also in Deep.
FP settings used for DD, Mono and Cancel coil settings. Cancel seemed a bit more sensitive.

Since I do not have another large mono I can not tell how good or bad the performance of my 30" CC is. The only indication of depth comparison that I have is a hammered copper bucket buried years ago under compact soil at 1 meter depth below the surface, GPX5000 with 16" mono was not able to get a signal from this target on any settings. The 4500 now with my new 30"CC gets a huge signal with a good 10" above the soil.

I got a 5 gram 23.5 Carats gold bar that I can get at 18" in air, but a smaller coil could be more sensitive to this bar.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: mylab on Thursday March 7 2019 17:27:46 AEDT PM
  

I have 4500. The FP settings are in Normal mode. I tried also in Deep.
FP settings used for DD, Mono and Cancel coil settings. Cancel seemed a bit more sensitive.

The only indication of depth comparison that I have is a hammered copper bucket buried years ago under compact soil at 1 meter depth below the surface, ............. The 4500 now with my new 30"CC gets a huge signal with a good 10" above the soil.


I am somewhat confused as I try to grasp when you say Normal mode so is that General Search mode or Normal timing (N) position of the Soil/Timings switch which is the strongest timing except for Sharp under Special ?

Now from your result on the hammered copper bucket in the ground at 1 metre and the 4500 & 30" CC coil producing a hugh signal at 10"(25cm) above the ground for an overall depth of 1.25 metres........ then that is still less than the depth displayed in the video of Nexus Standard MP V2 using the Dual 30" Figure 8 coil over the same hammered copper bucket at 1 metre depth which produced a signal at 18" (45cm) above the ground for an overall depth of 1.45 metres.






Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Thursday March 7 2019 19:48:50 AEDT PM
  
  

I have 4500. The FP settings are in Normal mode. I tried also in Deep.
FP settings used for DD, Mono and Cancel coil settings. Cancel seemed a bit more sensitive.

The only indication of depth comparison that I have is a hammered copper bucket buried years ago under compact soil at 1 meter depth below the surface, ............. The 4500 now with my new 30"CC gets a huge signal with a good 10" above the soil.


I am somewhat confused as I try to grasp when you say Normal mode so is that General Search mode or Normal timing (N) position of the Soil/Timings switch which is the strongest timing except for Sharp under Special ?

Now from your result on the hammered copper bucket in the ground at 1 metre and the 4500 & 30" CC coil producing a hugh signal at 10"(25cm) above the ground for an overall depth of 1.25 metrs........ then that is still less than the depth displayed in the video of Nexus Standard MP V2 using the Dual 30" Figure 8 coil over the same hammered copper bucket at 1 metre depth which produced a signal at 18" (45cm) above the ground for an overall depth of 1.45 metres.





Nexus Standard MP with dual 30" coil is superior to the GPX and for that matter to all other detectors in normal ground conditions to almost all targets and especially to pure copper items and others with very high conductivity.
On the video you mention the MP's Threshold was significantly reduced to make the detector completely silent during operation.
With some hum in the Threshold this copper bucket can be detected down to 2 meters in the ground with the MP and dual 30" coil. But these are the kind of targets I mentioned in another post that the IB detectors have the advantage to PI.
So if the metal composition is less pure then the PI gains a lot and very quickly.

The GPX 4500 with 30"CC gets a 6" stainless steel can from a kitchen scale at 2 meters. After some time I'll get some videos done, but I need to make sure this 30" CC is actually worth filming. It may happen some other smaller mono's out there to be better than my 30".


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Thursday March 7 2019 20:08:27 AEDT PM
  

I am somewhat confused as I try to grasp when you say Normal mode so is that General Search mode or Normal timing (N) position of the Soil/Timings switch which is the strongest timing except for Sharp under Special ?


I mean Normal timing in General search Mode.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: mylab on Friday March 8 2019 00:32:02 AEDT AM
  

The GPX 4500 with 30"CC gets a 6" stainless steel can from a kitchen scale at 2 meters.

After some time I'll get some videos done, but I need to make sure this 30" CC is actually worth filming.

 It may happen some other smaller mono's out there to be better than my 30".


If 2 metres is possible with the Nexus which is a further 29.5” (0.75 metre) than the GPX on the copper bucket using its Normal timing then that is impressive although you say this type of target the IB has the advantage over the PI.  

Could you perform a test using an empty standard aluminium soft drink can of 375ml capacity with the dimensions 130mm long and 65mm in diameter using FP settings in General Mode and Normal timing on your 4500 and 30" CC coil as a result with a 18” mono coil on my 4500 using those same settings was 46” (1.16 metres) when passing the can back and forth above the coil resting on the ground.

Also some videos would be good that you mentioned.




Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Friday March 8 2019 01:25:36 AEDT AM
  

If 2 metres is possible with the Nexus which is a further 29.5” (0.75 metre) than the GPX on the copper bucket using its Normal timing then that is impressive although you say this type of target the IB has the advantage over the PI.  

Could you to perform a test using an empty standard aluminium soft drink can of 375ml capacity with the dimensions 130mm long and 65mm in diameter using FP settings in General Mode and Normal timing on your 4500 and 30" CC coil as a result with a 18” mono coil on my 4500 using those same settings was 46” (1.16 metres) when passing the can back and forth above the coil resting on the ground.

Also some videos would be good that you mentioned.



Let's not forget that the MP in the this discussion is using dual 30" coil that is nearly twice the surface area of the 30"CC for the GPX. Twice surface area will already provide approximately 25% increase of sensitivity to big deep objects.
To compare fairly the GPX4500 with 30"CC to MP with dual 30" one would have to discount at least 20% from the MP results to account for the coil size differences other wise it is unfair battle.

We have here 330 ml standard for the soft drink cans. I'll look into the shops if I can get anything in 375 in the dimensions you provided and will let you know.
If all is correct with my coil the sensitivity increase from 18" mono to 30" CC (mono)  for 375 ml can, from calculation should be from 46" (116 cm) to 194 cm or 76" approximately.
I measure purely in air with the coil flat on the ground as I have no way to swing 2 meters high up.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: mylab on Friday March 8 2019 01:39:45 AEDT AM
  

If all is correct with my coil the sensitivity increase from 18" mono to 30" CC (mono)  for 375 ml can, from calculation should be from 46" (116 cm) to 194 cm or 76" approximately.

I measure purely in air with the coil flat on the ground as I have no way to swing 2 meters high up.


Very good, yes in air with the coil flat on the ground and passing the can back and forth above.
By using the aluminium drink can it is a universal test target that everyone is able to use for a comparison.
Will be interesting if your 30" CC coil can max out up at 1.94 metres or more. 


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Friday March 8 2019 03:12:56 AEDT AM
  
  

If all is correct with my coil the sensitivity increase from 18" mono to 30" CC (mono)  for 375 ml can, from calculation should be from 46" (116 cm) to 194 cm or 76" approximately.

I measure purely in air with the coil flat on the ground as I have no way to swing 2 meters high up.


Very good, yes in air with the coil flat on the ground and passing the can back and forth above.
By using the aluminium drink can it is a universal test target that everyone is able to use for a comparison.
Will be interesting if your 30" CC coil can max out up at 1.94 metres or more. 
I just realised I'm talking bs. The mistake I made with my calculation is that the size increase from 18" to 30", which is about 66% will add 33% to the sensitivity, but I added 66%. So your result os 46" multiplied by 1.33 would give 61" or about 155 cm. So the 30"CC should get the can at 155 cm.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: mylab on Friday March 8 2019 19:57:03 AEDT PM
Dontbstme have you set a date for your video tests with the MP & Pathfinder on gold nuggets that you mentioned in a previous thread on 31st January this year?

Also any date set yet on that genuine invitation to visit the golden triangle this year to see first hand what the MP & Pathfinder can do on the ground here that you mentioned in the same thread on 29th January this year?



Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Friday March 8 2019 20:39:40 AEDT PM
  
Dontbstme have you set a date for your video tests with the MP & Pathfinder on gold nuggets that you mentioned in a previous thread on 31st January this year?

Also any date set yet on that genuine invitation to visit the golden triangle this year to see first hand what the MP & Pathfinder can do on the ground here that you mentioned in the same thread on 29th January this year?


Those dates are not set yet. I expect all this to happen some time in the summer, June, July August, but it will depend on how ready I am with the Pathfinder. This one need a lot of work to be done.
There is a good chance that before hand I will send the 30" and possibly 41"CC to be tested in Oz.

Next week I am testing the 30"CC with the GPX4500 on highly mineralised grounds nicely loaded with Magnetite and with relatively high conductivity as well.

Today I'll look in the shops for a soft drink can that matches your dimensions and will get out for test. I'll try to put up some video too.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: mylab on Friday March 8 2019 21:19:38 AEDT PM
Thanks for the update and look forward to your aluminium drink can result if you able to access one and some further videos.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Saturday March 9 2019 01:43:34 AEDT AM
  
Thanks for the update and look forward to your aluminium drink can result if you able to access one and some further videos.

So there are no 375 ml cans here, but 330 (65 x 115 mm).
The 330 ml can was detectable at about 120 cm flat against the coil.
Today I was not able to get any of the targets like a couple of days ago. The hammered copper bucket was barely detectable in the ground and all air test results seemed somewhat ordinary.
I wonder if there is not something wrong with the detector as day to day performance does not seem to repeat.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: mylab on Saturday March 9 2019 09:18:24 AEDT AM
Maybe your CC coil is now creating some sort of issue for the GPX?
Has switching from Cancel to DD or Mono change things at all?
Also even try restoring all Factory Preset settings:
Below is from the user manual.
1 Turn the detector off.
2 Press and hold the On/ Off switch until the Reset Defaults menu appears (approx. 5–6 seconds).
3 Turn Function Select to the right to select All Settings.
4 Turn Setting left or right to restore all Factory Presets.
Note: When performing an All Settings reset, the settings for the four Custom Search Modes are preserved. This is to prevent your own favourite mode settings from accidentally being erased whilst allowing the LCD menu, Deep Mode and General Mode settings to be quickly restored to factory settings.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Saturday March 9 2019 18:50:44 AEDT PM
  
Maybe your CC coil is now creating some sort of issue for the GPX?
Has switching from Cancel to DD or Mono change things at all?
Also even try restoring all Factory Preset settings:
Below is from the user manual.
1 Turn the detector off.
2 Press and hold the On/ Off switch until the Reset Defaults menu appears (approx. 5–6 seconds).
3 Turn Function Select to the right to select All Settings.
4 Turn Setting left or right to restore all Factory Presets.
Note: When performing an All Settings reset, the settings for the four Custom Search Modes are preserved. This is to prevent your own favourite mode settings from accidentally being erased whilst allowing the LCD menu, Deep Mode and General Mode settings to be quickly restored to factory settings.
A coil is a coil. It can not be perfect one day and mediocre in another, especially made by someone like my self. I have very serious experience building coils and can assure you in this coil there is no fault of any kind.

Now regarding the settings of the detector this is different matter. I am quite confused with all those options that quite frankly can get longer than the Bible.
I probably should have written down the settings when the detector was doing well to make sure they stay the same or I can return to the same settings as it is impossible for me to remember every detail of what was what.
I'll get someone more experienced with this complicated thing to adjust it and see what will come out of it.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Sunday March 10 2019 01:25:47 AEDT AM
So it turns out the GPX4500 with my 30" CC in FP does not do incredible things, but with some extra settings everything comes in place.
My 600 grams simulated from Tin nugget made a signal at 53"+ (135 cm) and 5 grams 14K mens gold ring was detectable at 31.5" (80 cm).
The 330 ml soft drink can was detectable at 61" (155 cm).

I made a video, but the high swings got out of the frame as I was shooting alone and had no way to check before the end of the job. Tomorrow I'll repeat the video with better frame exposure so everything can be seen.



Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: egixe4 on Sunday March 10 2019 10:39:11 AEDT AM
Thanks for your work Dontbstme
I'm enjoying reading your posts


 ::62:: 


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: mylab on Sunday March 10 2019 19:45:08 AEDT PM
  

Tomorrow I'll repeat the video with better frame exposure so everything can be seen.


Thanks for the test results, appears impressive.
Look forward to viewing your video.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Monday March 11 2019 03:29:55 AEDT AM
Here is the video and a decent group of test targets. Only one Ozzy nugget I am afraid. That's all I got.

https://www.youtube.com/watch?v=NlqOLZviWms&feature=youtu.be (https://www.youtube.com/watch?v=NlqOLZviWms&feature=youtu.be)


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Reg Wilson on Monday March 11 2019 10:18:53 AEDT AM
Great video. Great result. I want one, and how soon can I get one?


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Doug on Monday March 11 2019 11:10:45 AEDT AM
  
Here is the video and a decent group of test targets. Only one Ozzy nugget I am afraid. That's all I got.

https://www.youtube.com/watch?v=NlqOLZviWms&feature=youtu.be (https://www.youtube.com/watch?v=NlqOLZviWms&feature=youtu.be)


What is the inductance, resistance and Q for the coil?
doug ::419::


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: GARY on Monday March 11 2019 11:27:31 AEDT AM
Interesting video results from your time & effort.

Being a bit of test freak myself here is a pic of my attempt at air testing a 375ml Aluminium Solo Lemon Drink Can above an 18" mono on my GPX5000.

Results for a clear signal response:
Coil used ------  18” Advantage Mono Nuggetfinder        
Search Mode ------ Deep                                                    
Gain ----- 10   Stabilizer ----- 10                                            
Audio Tone ---------- 34                                                        
Timings ----- Enhance ----------- Fine Gold-------------- Normal          
Target :            
Alum Can     42” (106cm)            41” (104cm)              46” (116cm)              
 


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Doug on Monday March 11 2019 11:55:18 AEDT AM
  
Great video. Great result. I want one, and how soon can I get one?

If this coil can reproduce these results over our GF soils then i believe this coil will blow the SAD7000  out of the water for depth even  when using the 19" dog coil or the Russian coils!
doug ::419::


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: sd220d Digger on Monday March 11 2019 13:21:30 AEDT PM
  
  
Great video. Great result. I want one, and how soon can I get one?

If this coil can reproduce these results over our GF soils then i believe this coil will blow the SAD7000  out of the water for depth even  when using the 19" dog coil or the Russian coils!
doug ::419::

Is this coil worth $4800 that is not even proven to find any gold nuggets in Australian Goldfields???


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Doug on Monday March 11 2019 13:31:44 AEDT PM
  
  
  
Great video. Great result. I want one, and how soon can I get one?

If this coil can reproduce these results over our GF soils then i believe this coil will blow the SAD7000  out of the water for depth even  when using the 19" dog coil or the Russian coils!
doug ::419::

Is this coil worth $4800 that is not even proven to find any gold nuggets in Australian Goldfields???


Good point! Needs to be tested ASOP in Australian goldfields.
Reg would be  a good person to do the testing.
doug ::419::


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Monday March 11 2019 15:27:12 AEDT PM
  
  
Here is the video and a decent group of test targets. Only one Ozzy nugget I am afraid. That's all I got.

https://www.youtube.com/watch?v=NlqOLZviWms&feature=youtu.be (https://www.youtube.com/watch?v=NlqOLZviWms&feature=youtu.be)


What is the inductance, resistance and Q for the coil?
doug ::419::
275uH and 0.25 Ohms. The details of the Litz wire are not going to be disclosed.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Monday March 11 2019 15:30:43 AEDT PM
  
Interesting video results from your time & effort.

Being a bit of test freak myself here is a pic of my attempt at air testing a 375ml Aluminium Solo Lemon Drink Can above an 18" mono on my GPX5000.

Results for a clear signal response:
Coil used ------  18” Advantage Mono Nuggetfinder        
Search Mode ------ Deep                                                    
Gain ----- 10   Stabilizer ----- 10                                            
Audio Tone ---------- 34                                                        
Timings ----- Enhance ----------- Fine Gold-------------- Normal          
Target :            
Alum Can     42” (106cm)            41” (104cm)              46” (116cm)              
 
Thanks for sharing Gary. Your top results tells me that my coil is on the right track with its sensitivity as the depth increase from 18" to 30" would be about 33% and it works just like that. 116 cm x 1.33=154.28cm I got just about 155cm.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Monday March 11 2019 15:35:03 AEDT PM
  
Great video. Great result. I want one, and how soon can I get one?
Thanks Reg.
The answer is as soon as this coil design gets proven in Oz. A 41" CC is coming soon too.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: IBGold on Monday March 11 2019 15:35:45 AEDT PM
  
  
  
  
Great video. Great result. I want one, and how soon can I get one?

If this coil can reproduce these results over our GF soils then i believe this coil will blow the SAD7000  out of the water for depth even  when using the 19" dog coil or the Russian coils!
doug ::419::

Is this coil worth $4800 that is not even proven to find any gold nuggets in Australian Goldfields???


Good point! Needs to be tested ASOP in Australian goldfields.
Reg would be  a good person to do the testing.
doug ::419::

I agree.

Regards, Ian.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Monday March 11 2019 15:36:30 AEDT PM
  
  
  
Great video. Great result. I want one, and how soon can I get one?

If this coil can reproduce these results over our GF soils then i believe this coil will blow the SAD7000  out of the water for depth even  when using the 19" dog coil or the Russian coils!
doug ::419::

Is this coil worth $4800 that is not even proven to find any gold nuggets in Australian Goldfields???

It will be.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: mylab on Wednesday March 13 2019 00:22:39 AEDT AM
I see Gary produced a similar result on a 375ml aluminium drink can in Normal timing as I did.
Now if I were to use the formula that Dontbsme used for an idea on the extra depth of a larger coil over a smaller coil then going from an 18” coil up to Reg’s 36” coil on a GPX in Normal timing the aluminium drink can would register an depth increase from 116cm up at 174cm.

As Reg is interested in testing Dontbstme’s 30”CC coil then I assume Reg is to test the 30”CC coil on the QED.
Reg could you test a 375ml aluminum drink can over your 36” coil resting on the ground using the QED in its strongest setting as is Normal timing on the GPX?


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Wednesday March 13 2019 02:10:16 AEDT AM
  
I see Gary produced a similar result on a 375ml aluminium drink can in Normal timing as I did.
Now if I were to use the formula that Dontbsme used for an idea on the extra depth of a larger coil over a smaller coil then going from an 18” coil up to Reg’s 36” coil on a GPX in Normal timing the aluminium drink can would register an depth increase from 116cm up at 174cm.

As Reg is interested in testing Dontbstme’s 30”CC coil then I assume Reg is to test the 30”CC coil on the QED.
Reg could you test a 375ml aluminum drink can over your 36” coil resting on the ground using the QED in its strongest setting as is Normal timing on the GPX?

The thing with larger coils is that the function of depth increments is not linear.
Let say with 18" you get the drink can at 1.16 cm and with 50% larger coil diameter you can get the extra 25% depth increment. This does not mean the depth increments will keep up on a coil 100% larger in diameter.
As coils get larger they loose sensitivity to smaller and/or medium size targets and begin to gain sensitivity to bigger targets.
The reason behind this phenomenon is the reduction of transmitted field intensity. We still use the same transmitter, but with the coil getting bigger the field becomes less intense.
Considering that the 4500 with my 30" CC gets my Aussie nugget at 15 cm (which is more than Garrett ATX with 12"DD can do) I would expect the coil size increase to Reg's 38" to keep up the depth increments for the soft drink can.

Come on Reg. Give us a hint, will ya?


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: sd220d Digger on Wednesday March 13 2019 13:13:39 AEDT PM
  
  
  
  
Great video. Great result. I want one, and how soon can I get one?

If this coil can reproduce these results over our GF soils then i believe this coil will blow the SAD7000  out of the water for depth even  when using the 19" dog coil or the Russian coils!
doug ::419::

Is this coil worth $4800 that is not even proven to find any gold nuggets in Australian Goldfields???

It will be.

For $4800 (one of your coils Don'tbullshitme and Candigger) I can buy two QED detectors and two 25" Nugget Finder coils and two smaller coils and find gold.   ::69::

What have your coils found for a price tag of $4800?....... Oh yeah, that's right......... Cans air tested @ 1.5 metres in the air   ::401::


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: sd220d Digger on Wednesday March 13 2019 13:17:30 AEDT PM
  
  
  
  
  
Great video. Great result. I want one, and how soon can I get one?

If this coil can reproduce these results over our GF soils then i believe this coil will blow the SAD7000  out of the water for depth even  when using the 19" dog coil or the Russian coils!
doug ::419::

Is this coil worth $4800 that is not even proven to find any gold nuggets in Australian Goldfields???

It will be.

For $4800 (one of your coils Don'tbullshitme and Candigger) I can buy two QED detectors and two 25" Nugget Finder coils and two smaller coils and find gold.   ::69::

What have your coils found for a price tag of $4800?....... Oh yeah, that's right......... Cans air tested @ 1.5 metres in the air   ::401::

Ok, that's not funny but do you see what I'm saying?
Proven versus unproven.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Reg Wilson on Wednesday March 13 2019 20:33:37 AEDT PM
I am working on a prospecting project at the moment. Will do some testing in a few days


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: mylab on Thursday March 14 2019 00:25:08 AEDT AM
  

 Will do some testing in a few days


Thanks Reg and I now realise your large mono is 38" and not 36" as I said before.
Be interesting how high the aluminium Can will register a response on the QED with that 38" mono.
Dontbstme's result at 155cm was with a smaller 330ml Can although of same diameter as the 375ml Can used in Gary's result at 116cm.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Thursday March 14 2019 06:36:59 AEDT AM
  

Dontbstme's result at 155cm was with a smaller 330ml Can although of same diameter as the 375ml Can used in Gary's result at 116cm.
In theory if I was to use 375 ml can then the air test would have gone to 165 cm, 10 cm (6.5%) more than what I got with 330 ml can.

Tomorrow I will be down to South BG on a super heavy mineralised site. It is a Vanadium mine first developed by the Germans in WW2. I will have with me Hristo Terziev a popular Bulgarian geologist to identify all of the rocks and soil conditions. I will ask him if we can take some soil measurements as well. Let see if the GPX will be able to do any GB on those conditions. There will be few more mono and DD coils from Detech and Minelab for the trials to make sure what ever the result with my 30"CC comes out is legitimate.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: GARY on Thursday March 14 2019 09:38:55 AEDT AM
  
  

Dontbstme's result at 155cm was with a smaller 330ml Can although of same diameter as the 375ml Can used in Gary's result at 116cm.


In theory if I was to use 375 ml can then the air test would have gone to 165 cm, 10 cm (6.5%) more than what I got with 330 ml can.

Tomorrow I will be down to South BG on a super heavy mineralised site. It is a Vanadium mine first developed by the Germans in WW2. I will have with me Hristo Terziev a popular Bulgarian geologist to identify all of the rocks and soil conditions. I will ask him if we can take some soil measurements as well. Let see if the GPX will be able to do any GB on those conditions. There will be few more mono and DD coils from Detech and Minelab for the trials to make sure what ever the result with my 30"CC comes out is legitimate.


The problem with using the results from Normal timing on the GPX with a mono coil is on mineralised ground as we all know, Normal timing is about useless and more so the higher the ground is mineralised. So the special timings such as Smooth, Enhance & Fine Gold are required to be used to cope with the hot ground.

Therefore looking at my results on the 375ml Solo drink can using either Enhance or Fine Gold, and hopefully my calculations are correct, then going from my 18" mono up to Reg’s 38" mono the Can in Fine Gold would increase out from 41” (104cm) to 63” (161cm) and in Enhance from 42” (106cm) out to 65” (165cm)

Also raising the Gain and using the Boost audio setting can play havoc with hot ground as well so it will be interesting if Dontbstme with his 30” CC on the GPX 4500 will handle the mineralised area he mentions to test his coil on.

Especially in his settings using Normal timing with his Gain up at 11, Stabilizer up at 20 max, Target Volume up at 10, Volume Limit up at 20 max. Audio Type in Boost and all others at FP in Deep Mode except for Response using Normal instead of Inverted.

Gary.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Thursday March 14 2019 15:40:25 AEDT PM
  
  
  

Dontbstme's result at 155cm was with a smaller 330ml Can although of same diameter as the 375ml Can used in Gary's result at 116cm.


In theory if I was to use 375 ml can then the air test would have gone to 165 cm, 10 cm (6.5%) more than what I got with 330 ml can.

Tomorrow I will be down to South BG on a super heavy mineralised site. It is a Vanadium mine first developed by the Germans in WW2. I will have with me Hristo Terziev a popular Bulgarian geologist to identify all of the rocks and soil conditions. I will ask him if we can take some soil measurements as well. Let see if the GPX will be able to do any GB on those conditions. There will be few more mono and DD coils from Detech and Minelab for the trials to make sure what ever the result with my 30"CC comes out is legitimate.


The problem with using the results from Normal timing on the GPX with a mono coil is on mineralised ground as we all know, Normal timing is about useless and more so the higher the ground is mineralised. So the special timings such as Smooth, Enhance & Fine Gold are required to be used to cope with the hot ground.

Therefore looking at my results on the 375ml Solo drink can using either Enhance or Fine Gold, and hopefully my calculations are correct, then going from my 18" mono up to Reg’s 38" mono the Can in Fine Gold would increase out from 41” (104cm) to 63” (161cm) and in Enhance from 42” (106cm) out to 65” (165cm)

Also raising the Gain and using the Boost audio setting can play havoc with hot ground as well so it will be interesting if Dontbstme with his 30” CC on the GPX 4500 will handle the mineralised area he mentions to test his coil on.

Especially in his settings using Normal timing with his Gain up at 11, Stabilizer up at 20 max, Target Volume up at 10, Volume Limit up at 20 max. Audio Type in Boost and all others at FP in Deep Mode except for Response using Normal instead of Inverted.

Gary.
This was only a test to see what I can get at maximum useable sensitivity of the detector with the 30"CC. My settings were far from the most favourable due to too much EMI.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Reg Wilson on Sunday March 17 2019 14:38:59 AEDT PM
Mylab, have just completed test with 375ml can on 38" coil.
To get a nice smooth GB I had to set the gain at 2 and the mode at 2 as well. GB was 100 and bias at 56.
There was too much too much EMI to have the settings hotter and still maintain a smooth ground balance. If I had set them higher I may have got a better result, but it would not have been the settings one could use for viable in the field detecting. I used a speaker as well. (not my favorite audio)
The max height above the coil for a positive 'dig me' signal was 131 cm


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: sd220d Digger on Sunday March 17 2019 20:54:11 AEDT PM
  
Mylab, have just completed test with 375ml can on 38" coil.
To get a nice smooth GB I had to set the gain at 2 and the mode at 2 as well. GB was 100 and bias at 56.
There was too much too much EMI to have the settings hotter and still maintain a smooth ground balance. If I had set them higher I may have got a better result, but it would not have been the settings one could use for viable in the field detecting. I used a speaker as well. (not my favorite audio)
The max height above the coil for a positive 'dig me' signal was 131 cm

Hi Reg.
I found when using a big coil, was that it worked best in the early hours of the morning when the atmospherics and electrical interferences were at their lowest.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Sunday March 17 2019 21:47:32 AEDT PM
  
Mylab, have just completed test with 375ml can on 38" coil.
To get a nice smooth GB I had to set the gain at 2 and the mode at 2 as well. GB was 100 and bias at 56.
There was too much too much EMI to have the settings hotter and still maintain a smooth ground balance. If I had set them higher I may have got a better result, but it would not have been the settings one could use for viable in the field detecting. I used a speaker as well. (not my favorite audio)
The max height above the coil for a positive 'dig me' signal was 131 cm
Thank you Reg. It is a good reference.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Sunday March 17 2019 21:50:40 AEDT PM
Here is another more detailed video test of the GPX4500 with 18"DD ML Commander, 18" Mono Detech Exelerator and 30" Nexus CC.
All coils were tested in the same settings all FP passing trough DD, Mono and Cancel RX settings.
I have made a video that demonstrates on the same test site what is the best depth I can get with all 3 coils at their best settings. It will be posted as soon as I get it processed.
There is also a video that demonstrates the Nexus Standard MP with dual 20" Ultima coil on the same site and the same day for a reference to how IB detectors react to large objects in comparison to PI detectors.

https://www.youtube.com/watch?v=NX8IpDUer94 (https://www.youtube.com/watch?v=NX8IpDUer94)


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: mylab on Monday March 18 2019 00:06:14 AEDT AM
  
Mylab, have just completed test with 375ml can on 38" coil.
To get a nice smooth GB I had to set the gain at 2 and the mode at 2 as well. GB was 100 and bias at 56.
There was too much too much EMI to have the settings hotter and still maintain a smooth ground balance. If I had set them higher I may have got a better result, but it would not have been the settings one could use for viable in the field detecting. I used a speaker as well. (not my favorite audio)
The max height above the coil for a positive 'dig me' signal was 131 cm

Reg thanks for your result on the 375ml drink Can including the settings you used on your QED with your 38” coil. As you said the settings for the test are more like one would use when detecting on the goldfield and I expect would also help to reduce any EMI out in the field since your large coil would be more prone to any EMI than one not so large.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: mylab on Monday March 18 2019 00:09:41 AEDT AM
  
Here is another more detailed video test of the GPX4500 with 18"DD ML Commander, 18" Mono Detech Exelerator and 30" Nexus CC.

Thanks to you also Dontbstme for another test video which I will now watch with interest.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Monday March 18 2019 00:39:06 AEDT AM
  
Mylab, have just completed test with 375ml can on 38" coil.
To get a nice smooth GB I had to set the gain at 2 and the mode at 2 as well. GB was 100 and bias at 56.
There was too much too much EMI to have the settings hotter and still maintain a smooth ground balance. If I had set them higher I may have got a better result, but it would not have been the settings one could use for viable in the field detecting. I used a speaker as well. (not my favorite audio)
The max height above the coil for a positive 'dig me' signal was 131 cm
I have a question. How do these settings translate to GPX settings? I take it you used QED for the test, but I have no way to understand what do these settings mean since I have never seen or used QED.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: mylab on Monday March 18 2019 02:43:07 AEDT AM
  
Thanks to you also Dontbstme for another test video which I will now watch with interest.

I would say why the copper bucket in the ground is producing a better result than your air test of a similar bucket is maybe due to some leaching of the copper bucket being in the ground over that time creating a larger footprint or some say a halo effect?


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Monday March 18 2019 04:15:04 AEDT AM
The next video is to demonstrate the maximum useable sensitivity of GPX 4500 with the 30" CC, 18" DD from ML and 18" mono from Detech.
The 330 ml soft drink can comes at 145 cm with the 30"CC and in working condition of the detector. These are still not the best settings, just the ones I managed to conjure up for the moment.
Tomorrow I am going to make the ultimate test of the GPX 4500 with the 30" CC on concentrated magnetite on the black sand beach. Magnetite and salty sea water together. Let see what will come out of it.

https://www.youtube.com/watch?v=54dDful1nlE&feature=youtu.be (https://www.youtube.com/watch?v=54dDful1nlE&feature=youtu.be)


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Reg Wilson on Monday March 18 2019 09:30:29 AEDT AM
When I get the opportunity I shall do the can test with a GPX and the 38" coil and post the results.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: GARY on Monday March 18 2019 11:23:59 AEDT AM
An interesting video Dontbstme, which I also enjoyed due to my air test addiction, so I just had to analyse your result with your 30” CC coil on the GPX 4500 in Enhance timing on the Drink Can, it being the common target for the comparison.
 
As you said in a previous post those settings you used on the 4500 with your 30” CC coil were not favourable due to too much EMI when you achieved 155cm (61”) which was 24cm (9”) more than Reg’s result at 131cm (51.5”)”, and you were using a smaller 330ml Drink Can.

Then if your theory holds true of an extra 6.5% depth if you were using a 375ml Drink Can then your result would have increased to 165cm (65”), a further 34cm (13”) however using FP settings in Normal timing, and if I am correct your result was 120cm (47”). Increase that by 6.5% for a 375ml Drink Can and the result would increase to 128cm (50”) compared to 131cm (51.5”) with Reg’s 38” mono on his QED.

Now you did mention to do further tests down South BG on a super mineralise site with the GPX and 30”CC coil and see if the GPX could GB on those conditions. Therefore I assume your video is at that test site since you had to revert to using Enhance due to the ground conditions.

I see from your results on the 330ml Drink Can using FP settings in Enhance timing the best air depth with your 30” CC coil was 128cm (50”). Then if you add that 6.5% for a 375ml Drink Can your result would increase to 136cm (53.5”)

If I refer back to my air depth result using Enhance with the 18” mono on the 375ml Drink Can and my result at 106cm(42”) then if I was to use your basic rule to calculate the distance if I was to use my 25” mono the result would increase to 122cm (48”).

And if I were to use Reg’s 38” mono and calculate the increased distance from my 18” mono the result on the 375ml Drink Can should be 135cm (53”) close to your best at 136cm (53.5”) which is only 2cm (20mm or 0.7”) more than Reg’s 131cm (51.5”) result with his 38” mono on the QED.

I now see in your Part 2 video with the 30”CC for extra sensitivity on the GPX4500 the settings you changed in the Deep Search Mode menu apart from FP settings was raising the Target Volume from 8 up to 15 and reducing the Threshold to Zero. Your result now on the 330ml Drink Can increased from 136cm (53.5”) up to 145cm (57”). Add the 6.5% if a 375ml Drink Can and it is up to 154cm (60.6”) You say these are still not the best settings, just the ones you managed to conjure up for the moment.

Increasing settings is all good and well as it depends on ground conditions, atmospherics, the coil, target type and size etc.
 
I hope all my results are correct as it sure gave me a head spin to calculate.

Look forward to your next test video.

Gary.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Monday March 18 2019 17:09:54 AEDT PM
  
An interesting video Dontbstme, which I also enjoyed due to my air test addiction, so I just had to analyse your result with your 30” CC coil on the GPX 4500 in Enhance timing on the Drink Can, it being the common target for the comparison.
 
As you said in a previous post those settings you used on the 4500 with your 30” CC coil were not favourable due to too much EMI when you achieved 155cm (61”) which was 24cm (9”) more than Reg’s result at 131cm (51.5”)”, and you were using a smaller 330ml Drink Can.

Then if your theory holds true of an extra 6.5% depth if you were using a 375ml Drink Can then your result would have increased to 165cm (65”), a further 34cm (13”) however using FP settings in Normal timing, and if I am correct your result was 120cm (47”). Increase that by 6.5% for a 375ml Drink Can and the result would increase to 128cm (50”) compared to 131cm (51.5”) with Reg’s 38” mono on his QED.

Now you did mention to do further tests down South BG on a super mineralise site with the GPX and 30”CC coil and see if the GPX could GB on those conditions. Therefore I assume your video is at that test site since you had to revert to using Enhance due to the ground conditions.

I see from your results on the 330ml Drink Can using FP settings in Enhance timing the best air depth with your 30” CC coil was 128cm (50”). Then if you add that 6.5% for a 375ml Drink Can your result would increase to 136cm (53.5”)

If I refer back to my air depth result using Enhance with the 18” mono on the 375ml Drink Can and my result at 106cm(42”) then if I was to use your basic rule to calculate the distance if I was to use my 25” mono the result would increase to 122cm (48”).

And if I were to use Reg’s 38” mono and calculate the increased distance from my 18” mono the result on the 375ml Drink Can should be 135cm (53”) close to your best at 136cm (53.5”) which is only 2cm (20mm or 0.7”) more than Reg’s 131cm (51.5”) result with his 38” mono on the QED.

I now see in your Part 2 video with the 30”CC for extra sensitivity on the GPX4500 the settings you changed in the Deep Search Mode menu apart from FP settings was raising the Target Volume from 8 up to 15 and reducing the Threshold to Zero. Your result now on the 330ml Drink Can increased from 136cm (53.5”) up to 145cm (57”). Add the 6.5% if a 375ml Drink Can and it is up to 154cm (60.6”) You say these are still not the best settings, just the ones you managed to conjure up for the moment.

Increasing settings is all good and well as it depends on ground conditions, atmospherics, the coil, target type and size etc.
 
I hope all my results are correct as it sure gave me a head spin to calculate.

Look forward to your next test video.

Gary.

It all sounds right, well until we establish that its not. But for now its right. ::62::


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Monday March 18 2019 17:26:05 AEDT PM
The last video is still not on a mineralised test site, at least not according to the Nexus Standard MP. The MP is a huge gun there and it outguns the GPX hands down.
For some reason me and my friend had difficulties to ground balance at the high power modes, that's why I decided to use the Enhance.

Next video that will come out today is from a real mineralised site (we call it Peregruzka - it means Overload from Russian) where all soil is littered with millions of magnetic rocks of all kinds. The site is near an ancient gold mine, long abandoned.
The video is just coming out of my pc rendering program.

Today I am going on the black sand beach to use test conditions where not one IB detector (short of Nexus MP) can work. Nexus MP is very shallow in those conditions with standard size coils, just up to 3" for larger coins. Minelab CTX3030 goes in overload mode at zero sensitivity and XP Deus can not see a coin in what ever setting right on top of the sand/soil. Fisher F75 goes haywire half meter above the back sand. Not working at all.
Combined with the salt water on the beach this should be a tough one for any detector.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Tuesday March 19 2019 04:49:16 AEDT AM
Here it is. Finally a video on highly mineralised soil, still not comparable to Oz horrific grounds, but bad enough for IB detectors to chalk on it.
Tomorrow I will post the video from today from another test site 270 km away from my town. That one is a master piece as the magnetite in there is in piles, huge piles, plus all of the crap left over by agricultural works as the field is arable land. Black highly conductive soil.

https://www.youtube.com/watch?v=LpElDur7dhI&feature=youtu.be (https://www.youtube.com/watch?v=LpElDur7dhI&feature=youtu.be)


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Tuesday March 19 2019 05:32:47 AEDT AM
Mechanical stability test of the 30"CC.

https://www.youtube.com/watch?v=NYvooEakFyk (https://www.youtube.com/watch?v=NYvooEakFyk)


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: WM6 on Tuesday March 19 2019 08:46:58 AEDT AM
Brave 1m digger. Seems coil work stable. Congratulation.

Here we are back to the main problems of deep diggers.
Namely how to distinguish between Gold nugget and tin can (or other crap)
at 1m of depth - to not to dig ten 1m holes per day in vain.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Tuesday March 19 2019 18:24:53 AEDT PM
  
Brave 1m digger. Seems coil work stable. Congratulation.

Here we are back to the main problems of deep diggers.
Namely how to distinguish between Gold nugget and tin can (or other crap)
at 1m of depth - to not to dig ten 1m holes per day in vain.
In Europe I would dig just about any deep sounding target, regardless, but in Oz I am not jealous one bit to those that have to dig the old timers crap. I am afraid there is no way around this. In highly mineralised conditions discrimination is impossible at depth, much less so against tin cans. Not a chance.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Tuesday March 19 2019 18:52:31 AEDT PM
Here is the last video on highly mineralised soil that I am going to be presenting from Bulgaria. Next is the land of Oz.

The test on the black sand beach was impossible for the detector to do. Even at all gain settings like Target Volume 1, RX Gain 1, Stabiliser 1 all in Enhanced mode and DD coil configuration the detector was giving very strong reactions to the magnetite combined with the sea salt water. The magnetite was concentrated with no normal sand around. Possibly with a smaller coil things could work out.

So here is the video from the magnetite loaded arable land just above the black sand beach.

https://www.youtube.com/watch?v=we1C9hZzQKo&feature=youtu.be (https://www.youtube.com/watch?v=we1C9hZzQKo&feature=youtu.be)


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Wednesday March 20 2019 04:54:06 AEDT AM
Discrimination test of GPX 4500 with Nexus 30"CC.

https://www.youtube.com/watch?v=y9sSsyuS-wI&feature=youtu.be (https://www.youtube.com/watch?v=y9sSsyuS-wI&feature=youtu.be)


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: mylab on Thursday March 21 2019 00:06:37 AEDT AM
Well done to you Dontbstme on your video tests with your 30” CC coil on a GPX 4500.

Also for the way you performed your tests displaying each setting to the video camera that is to be used for a particular test. You were genuine in the way you presented your test results using different targets of size and composition both for the air tests and buried in the ground tests, as well the buried in mineralised ground tests.

The only other testing left for your CC coils is how well they would operate on and through mineralised ground in Australia.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Thursday March 21 2019 03:02:20 AEDT AM
  
Well done to you Dontbstme on your video tests with your 30” CC coil on a GPX 4500.

Also for the way you performed your tests displaying each setting to the video camera that is to be used for a particular test. You were genuine in the way you presented your test results using different targets of size and composition both for the air tests and buried in the ground tests, as well the buried in mineralised ground tests.

The only other testing left for your CC coils is how well they would operate on and through mineralised ground in Australia.


Thank you mylab.

The coil was sent today to Australia and should arrive on Tuesday next week. By the end of next week I hope to have some preliminary reports.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Monday March 25 2019 19:40:44 AEDT PM
The 30"CC has arrived in Oz today. Tomorrow I will have some first time testing done.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: bugwhiskers on Monday March 25 2019 20:26:05 AEDT PM
  
Brave 1m digger. Seems coil work stable. Congratulation.

Here we are back to the main problems of deep diggers.
Namely how to distinguish between Gold nugget and tin can (or other crap)
at 1m of depth - to not to dig ten 1m holes per day in vain.

Indeed, you want to dig in a vein, not in vain.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Monday March 25 2019 20:51:19 AEDT PM
  
  
Brave 1m digger. Seems coil work stable. Congratulation.

Here we are back to the main problems of deep diggers.
Namely how to distinguish between Gold nugget and tin can (or other crap)
at 1m of depth - to not to dig ten 1m holes per day in vain.

Indeed, you want to dig in a vein, not in vain.

Well this could be a new beginning.

https://www.youtube.com/watch?v=y9sSsyuS-wI&t=47s (https://www.youtube.com/watch?v=y9sSsyuS-wI&t=47s)


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: mylab on Tuesday March 26 2019 00:44:03 AEDT AM
  

The 30"CC has arrived in Oz today. Tomorrow I will have some first time testing done.


Dontbstme you certainly have taken up the challenge to see if your 30” CC coil can handle the ground down under in Australia.

As for digging 1 metre holes for trash I wonder how many operators have dug to that depth for a piece of iron in hard goldfield ground. Surely if you are an experienced operator you know once you start digging you have good idea that the ground is natural and untouched so the target at the end of the dig is going to be gold, well that is my view. 

I was interested on how the 30” CC coil was able to discriminate out the iron objects in the video tests however to what depth if those objects were in the ground, although iron buried out in natural goldfield ground I believe would not be at depths of 1 metre. I suppose the exception would be in a creek situation where ground is being moved to build depth over a piece of iron.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Tuesday March 26 2019 02:15:40 AEDT AM
  
  

The 30"CC has arrived in Oz today. Tomorrow I will have some first time testing done.


Dontbstme you certainly have taken up the challenge to see if your 30” CC coil can handle the ground down under in Australia.

As for digging 1 metre holes for trash I wonder how many operators have dug to that depth for a piece of iron in hard goldfield ground. Surely if you are an experienced operator you know once you start digging you have good idea that the ground is natural and untouched so the target at the end of the dig is going to be gold, well that is my view. 

I was interested on how the 30” CC coil was able to discriminate out the iron objects in the video tests however to what depth if those objects were in the ground, although iron buried out in natural goldfield ground I believe would not be at depths of 1 metre. I suppose the exception would be in a creek situation where ground is being moved to build depth over a piece of iron.


The concern regarding deep Iron involves the old timer sites in Oz, which at the most part are a mess of trash.

I did not have the time to go out and dig real targets to check how deep the Iron can be rejected with the GPX, but for sure the level 10 of IR and pure untouched non-ferrous deep signals in the ground is a hell impressive result to see as no IB detector is able to show such discrimination on my test site. My detectors will beat for sure any other IB on deep discrimination, but the GPX definitely caught me off guard with my own coil.
The coin I use on the video is 20.5 mm, but the one in the ground is 18mm, not 20.5. I just did not have the same small coin to use in the video. So in full IR the GPX with the 30"CC blasted an 18mm coins at over 20", 12" of which are under ground. I have not seen anything to come close to this display.

I am going to construct 11'5" CC (by the end of next week) for the GPX with the special purpose to explore how well the discrimination of this detector will go with the CC's in depth. I will also build a 20"DD again to see how the discrimination will work and if there will be any difference between DD and CC discrimination with the GPX.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: jrbeatty on Tuesday March 26 2019 08:53:38 AEDT AM
Dontbstme:  Watching this thread with considerable interest.

 ::402:: with your Aussie tests.

Quote from: Bugs
Indeed, you want to dig in a vein, not in vain.

Very droll, Howard.  ::419::


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: WM6 on Tuesday March 26 2019 10:27:16 AEDT AM
  
Dontbstme:  Watching this thread with considerable interest.

 ::402:: with your Aussie tests.

Quote from: Bugs
Indeed, you want to dig in a vein, not in vain.

Very droll, Howard.  ::419::

Actually i mean "in vain" or all day futile dig of about 10 holes at 1m of depth..


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: GARY on Tuesday March 26 2019 10:53:17 AEDT AM
  

 I will also build a 20"DD again to see how the discrimination will work and if there will be any difference between DD and CC discrimination with the GPX.


I wonder since NF is to release a 25"DD then to what depths it may discriminate too on a GPX. 

Also how the 25"DD would stack up against the 30"CC to cope with Oz ground in the deepest Soil / Timing and for an outright in-ground depth test comparison.

Gary.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: WM6 on Tuesday March 26 2019 10:57:00 AEDT AM
  

Well this could be a new beginning.


Thanks for interesting test.

What about stacked buried different targets?

Par example: gold nugget/coin buried at 50cm of depth under (in vertical line) iron wedge buried at 20cm?


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Tuesday March 26 2019 16:30:37 AEDT PM
  
  

Well this could be a new beginning.


Thanks for interesting test.

What about stacked buried different targets?

Par example: gold nugget/coin buried at 50cm of depth under (in vertical line) iron wedge buried at 20cm?

GPX exhibits excellent discrimination, but it has a slow recovery speed. It will never find anything under Iron no matter the coil configuration or coil attached. This kind of discrimination is a treat that only Nexus MP can offer with its Silver Scout coil, but not at depth of 50 cm for a coin.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Tuesday March 26 2019 16:31:50 AEDT PM
  
  

 I will also build a 20"DD again to see how the discrimination will work and if there will be any difference between DD and CC discrimination with the GPX.


I wonder since NF is to release a 25"DD then to what depths it may discriminate too on a GPX. 

Also how the 25"DD would stack up against the 30"CC to cope with Oz ground in the deepest Soil / Timing and for an outright in-ground depth test comparison.

Gary.

I am going to build a 20"DD from Carbon Fiber and compare the discrimination to the CC.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: sd220d Digger on Tuesday March 26 2019 19:56:58 AEDT PM
  
  
  

Well this could be a new beginning.


Thanks for interesting test.

What about stacked buried different targets?

Par example: gold nugget/coin buried at 50cm of depth under (in vertical line) iron wedge buried at 20cm?

GPX exhibits excellent discrimination, but it has a slow recovery speed. It will never find anything under Iron no matter the coil configuration or coil attached. This kind of discrimination is a treat that only Nexus MP can offer with its Silver Scout coil, but not at depth of 50 cm for a coin.

Who is your tester of this 30" coil of yours Alie?

So you are saying your 30" coil is not any good for gold detecting? ( huge gold nuggets @ 1.5 - 2  metres)
And does that mean your price tag of $4800 for this coil is not worth the huge amount of money that only rich people can afford?


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: sd220d Digger on Tuesday March 26 2019 21:13:54 AEDT PM

Herman, comment withdrawn due to your no reply.

Gullible people will always get SUCKED in to outrageous claims with no results.






Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Wednesday March 27 2019 05:26:51 AEDT AM
The coil works in Oz on mineral level 7 out of 10 according to tester estimate.
The first test on GPX5000 was a bit misleading as the 5000 does not seem to cope well with this coil, but older 4500 model does. Mine is 4500 from 2011 and it works perfect. I will wait for next more detailed tests with older 4500 to see what come out of it.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Wednesday March 27 2019 05:37:46 AEDT AM
There are new results to come. So the first test I will consider irrelevant for now.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Reg Wilson on Wednesday March 27 2019 09:19:45 AEDT AM
What about your coil on QED. I think most people on this forum are more interested in how it performs, or if it performs on QED. The weight situation is also of more interest with this combination.
You come on this forum flogging your large but expensive coil, and ignore the QED. Not so clever.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: GARY on Wednesday March 27 2019 09:49:26 AEDT AM
Since a DD coil does not operate well on the QED then it appears a CC coil is similar in the way it operates?

Gary.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Reg Wilson on Wednesday March 27 2019 10:39:12 AEDT AM
Well Gary a DD does work on a QED, but only one D operates. I'm interested to see if the CC coil will work on a QED. I already have large coils that work on GPX or QED, and my guess is that they are damned close to the performance of the CC coil, but are susceptible to high mineralization noise.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Wednesday March 27 2019 14:30:31 AEDT PM
  
What about your coil on QED. I think most people on this forum are more interested in how it performs, or if it performs on QED. The weight situation is also of more interest with this combination.
You come on this forum flogging your large but expensive coil, and ignore the QED. Not so clever.

Reg I am not ignoring QED. Not one little bit. Just got no one available to test with it. After the tests are done with the people I work we can arrange probably some tests with QED too.
ML various GPX models seem to exhibit huge difference in behaviour to the same coil, which I find disturbing as changing coil parameters from one model to another is impossible for such expensive coil constructions. If I have to change my coils every year I will never make anything out of it.
So in this regard QED may prove to be a better successor for these coils than Minelab.

It also occur to me that if the QED happens to work a lot better with my CC than the GPX I can easily design a huge Mono for the QED that will be at a lot more favourable price tag than the CC as mono is not any near as complcated to manufacture like huge CC or DD coils.


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: sd220d Digger on Saturday March 30 2019 22:22:50 AEDT PM
  
There are new results to come. So the first test I will consider irrelevant for now.


Sounds like you have some work to do on your coils.



Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: mylab on Sunday March 31 2019 00:30:03 AEDT AM
  
The coil works in Oz on mineral level 7 out of 10 according to tester estimate.
The first test on GPX5000 was a bit misleading as the 5000 does not seem to cope well with this coil, but older 4500 model does. Mine is 4500 from 2011 and it works perfect. I will wait for next more detailed tests with older 4500 to see what come out of it.

Dontbstme I can’t seem to find those 1st test results as that GPX5000 may of had some sort of a problem and maybe the tester should have tested another 5000. Also why an earlier model 4500 can cope with your coil and not a later model  is a mystery. Whatever the issue I still look forward to the next more detailed test results with your 30” CC coil on the older 4500 and the settings it used over those, as I recall, 4 test targets of various sizes.

Also were the previous test target results with the 5000 an in ground test and do you know if the next detailed test target results with an older 4500 are to be an in the ground test?


Title: Re: 30" CC for Minelab GPX, GP, SD and similar.
Post by: Dontbstme on Sunday March 31 2019 16:43:42 AEDT PM
  
  
The coil works in Oz on mineral level 7 out of 10 according to tester estimate.
The first test on GPX5000 was a bit misleading as the 5000 does not seem to cope well with this coil, but older 4500 model does. Mine is 4500 from 2011 and it works perfect. I will wait for next more detailed tests with older 4500 to see what come out of it.

Dontbstme I can’t seem to find those 1st test results as that GPX5000 may of had some sort of a problem and maybe the tester should have tested another 5000. Also why an earlier model 4500 can cope with your coil and not a later model  is a mystery. Whatever the issue I still look forward to the next more detailed test results with your 30” CC coil on the older 4500 and the settings it used over those, as I recall, 4 test targets of various sizes.

Also were the previous test target results with the 5000 an in ground test and do you know if the next detailed test target results with an older 4500 are to be an in the ground test?

I deleted the results with the 5000 as they did not represent everything for the 30"CC that I need to see and also the 30"CC needs construction upgrade to handle the fine timings on 5000, which are not present in 4500. This is why 4500 works with the 30"CC flawlessly and not so the 5000.

I also considered that 30"CC may not be of a huge interest to Australian market as in ideal conditions 30" coil will not add more than 10% depth over 25" NF mono. 10% depth increase is not enough to justify the price difference (no matter the manufacturing costs involved) and prospectors do not seem to be interested in proper discrimination, which I find odd considering the old timer sites.

I will move to 41"CC construction soon with pre calculated weight below 1.5 kg. The 41" coil will add average of 30% depth increase over 25" mono coil, that is if the GPX do not put a brake on this because of existing RX in the CC. I do not know how the GPX is processing the RX signals and loop presence exactly. This needs to be measured in detail. I suspect that the discrimination will come at some cost of depth, but need to see to what extend.
If the loss of depth is too much because of RX coil in the design I will consider constructing simple mono coils instead for gold prospecting.
For treasure hunting all that was said above is quite irrelevant as treasure hunting does not need all of those super fine timings that 5000 utilise.