RELIC HAWK

[eclipse]

... or coins, no matter what - everything which would effect phase shift there so you can adjust it more precise, ML are using this small coil for that purpose.

I've seen X-ray of such coil somewhere, small coil inside the search coil, nothing else

[Fred]

... or coins, no matter what - everything which would effect phase shift there so you can adjust it more precise, ML are using this small coil for that purpose.

I've seen X-ray of such coil somewhere, small coil inside the search coil, nothing else

Hi,
That´s interesting,if Max used a 1mh it could explain the problems he encountered.
What would be the purpose to use a separate small coil instead of the main one and adjust phase shift with a loop of wire like in other MD´s ?
regards,
Fred.

[KingJL]

Hi,
Also, apart the iron detection at far... the detector works as expected... and is also about deep about detection... so it's only a small thing... maybe related to a schematic mistake or to something strange at ML design.

Max,
The more I research this, the more that I believe this is a common problem with all totally analog VLFs. Some models get around this by not being so sensitive. I think the reason for this can be understood by studying Whites patent for their VDI. In the patent information, it finds that the weak iron (iron at a distance) 'smears' (is not consistant phase angle) across the VDI. Looking at the code for the VDI, the phase angle is determined each time the GND channel is sampled and is above the threshold. In weak iron, the phase angle varies randomly over 180 degrees. The way that Whites Spectrum Eagle, XLT, DFX discriminate this is by the inconsistancy of the phase response. They can do this because they are uPC controlled and maintain a response level (maintained within the fade window time period) for every 9 degrees of phase angle. I am not sure that you can totally eliminate/discriminate this with current analog circuitry.

Regards,
J. L. King

[nakky]

... or coins, no matter what - everything which would effect phase shift there so you can adjust it more precise, ML are using this small coil for that purpose.

I've seen X-ray of such coil somewhere, small coil inside the search coil, nothing else

Eclipse,do you mean this.Grt Nakky.

[kt315]

...

[Max]

Max,
The more I research this, the more that I believe this is a common problem with all totally analog VLFs. Some models get around this by not being so sensitive. I think the reason for this can be understood by studying Whites patent for their VDI. In the patent information, it finds that the weak iron (iron at a distance) 'smears' (is not consistant phase angle) across the VDI. Looking at the code for the VDI, the phase angle is determined each time the GND channel is sampled and is above the threshold. In weak iron, the phase angle varies randomly over 180 degrees. The way that Whites Spectrum Eagle, XLT, DFX discriminate this is by the inconsistancy of the phase response. They can do this because they are uPC controlled and maintain a response level (maintained within the fade window time period) for every 9 degrees of phase angle. I am not sure that you can totally eliminate/discriminate this with current analog circuitry.

Regards,
J. L. King

Hi,
I think you're probably right about that. All my efforts to give no weak iron detection give just reduction of the problem but not complete solution of it.

Maybe an optimized coil could only partially solve that but, cause device is so sensitive, it's nearly impossible eliminate totally that behaviour in that analog design.

It will be easy know about that... cause people who had/have RH can try with a piece of soft iron (an cheap ... bad hammer) and see if detector see that when it's at e.g. 30cm or more... it's kind of cracked response but confusing in real search.

At less depth they will see no detection at all of the hammer.

If it's so, they must also know that cause must be infrequent they dig soft iron stuff at 30-40cm range, when in disc mode.

This do not apply to e.g. horseshoes cause they're actually of steel , not soft iron.

I hope someone could tell us what's real behaviour on soil... and if soft iron stuff is picked up at deep from time to time.

Kind regards,
Max

[eclipse]

This is sovereign coil, not the coil I've seen.
Perpahs wasnt on this forum it was long time ago.
But hey there it is - the small coil.
Also you've seen RH original board, have you noticed that
there isn't a coil on the board.

[Max]

...

Hi,
I think you wanna mean this is not a RH's coil. Right.

Nakky told us before...I presume, he wanna just show us that there's the small coil also in Sov.'s coils.

But in these last ones there's preamp pcb too...thing that it isn't in RH's coil.

Kind regards,
Max

[tiktak]

Hi

Hi,
Max.
How are you?
Ivconic sayed nothing in coil.I belive him.
The secret is in how deviece design.
I am shore that there are problems with iron when the unit is not properly tuned but.......which doesnt.Most are toys.And we are talking about deep targets here not hols.I never used Saxon1 or Nexus but I am doubting they can compare military quality and Ideas.Right?
So.
When I have time I will finish this PCB too and will report here.
Wish you luck with this last step.
But it must be the coil.!!!!
To tell you the truth I havent sleep last night and have tryed many coil arangments because I still cant solve my ZN probleme.Remember?
I have tryed 3 diferent coils acording pictures you post.Same wire,same numbers 100/105 but.....This ZN probleme.I have tryed many coins with same value all with ZN colour.And some are detected!!!So maybe the coins are composed of high % IRON?
But even if so on my first TGS disc is PERFECT!!!
And this isnt.For example with first with disc at max I ignore 10c,50c,1e coins and stil detect silver.And with second afther the foil I loose sudemly all Ni,ZN ALL AG also CU ALLL.Very,Very strange.
But the thing I wanned to tell you is that I have conrcted the coil from first RH bulgarian hand drawn schematic.The performance is poor no meter how nulled.But the important thing is that I get EXACLY the same sound as RH!!!!A little bitt quiet but EXACLY same!So its near.Very near.The frequency were 32. so how can reduce to 14 keeping same size coil?/this is with TGS TX !!!!/
This will work for both projects!And the coil is extremly stabile!!I havent saw such thing.Just woulnd and placed on table,conected to TGS,turn on and there are a lot of noises.TVs,internet,moovment of wires.But with this coil not at all.
I think this is interesting.
See you

[Max]

Hi,
Max.
How are you?
Ivconic sayed nothing in coil.I belive him.
The secret is in how deviece design.
I am shore that there are problems with iron when the unit is not properly tuned but.......which doesnt.Most are toys.And we are talking about deep targets here not hols.I never used Saxon1 or Nexus but I am doubting they can compare military quality and Ideas.Right?
So.
When I have time I will finish this PCB too and will report here.
Wish you luck with this last step.
But it must be the coil.!!!!
To tell you the truth I havent sleep last night and have tryed many coil arangments because I still cant solve my ZN probleme.Remember?
I have tryed 3 diferent coils acording pictures you post.Same wire,same numbers 100/105 but.....This ZN probleme.I have tryed many coins with same value all with ZN colour.And some are detected!!!So maybe the coins are composed of high % IRON?
But even if so on my first TGS disc is PERFECT!!!
And this isnt.For example with first with disc at max I ignore 10c,50c,1e coins and stil detect silver.And with second afther the foil I loose sudemly all Ni,ZN ALL AG also CU ALLL.Very,Very strange.
But the thing I wanned to tell you is that I have conrcted the coil from first RH bulgarian hand drawn schematic.The performance is poor no meter how nulled.But the important thing is that I get EXACLY the same sound as RH!!!!A little bitt quiet but EXACLY same!So its near.Very near.The frequency were 32. so how can reduce to 14 keeping same size coil?/this is with TGS TX !!!!/
This will work for both projects!And the coil is extremly stabile!!I havent saw such thing.Just woulnd and placed on table,conected to TGS,turn on and there are a lot of noises.TVs,internet,moovment of wires.But with this coil not at all.
I think this is interesting.
See you

Hi,
sure there isn't any pcb inside coil! We know that... cause RH is different from e.g. Sov design... with preamp inside coil housing.
My problem at coil is maybe related just with wires etc.


About coils between TGS and RH they are different... you have 1mH on RH at TX and 5.75mH at standard tesoro's for TGS or other old uMax.

The fact you hear noise with handmades means maybe shield is better in RH ones than your homemades... I have to say also that even original tesoro's are not totally shielded from noise... they pick-up some commutation noise quite easy.

About disc issues... it's related to phase shift: wrong phase shift at coil... wrong disc... like low sens to particular metals... happens with silver but also others...expecially those that give not big shifts just few... considering mass of the object.

You'll e.g. don't see it happens easy with copper... but with zinc is pretty easy to see if something is wrong at coil.

Kind regards,
Max

[tiktak]

Hi,

Hi,
Max.
It make sense.I will keep making new coils till I made right.How can I change the setting so the faseshift is good.
About the coils.Firs I test them unshielded.And in this set both were without shield.So TGS original coil is making a lot of noises because of this.And this RH ones is with low sens but no sound all.

[Fred]

Hi Tiktak ,
To change phase you must adjust coils relative positions and observe with a scope.So you will have to adjust them for phase AND best nulling, wicht becomes more complicated.A>nd this with the shields , as they changes everything too (Without shields sensitivity is much better).
Regards,
Fred.

[tiktak]

Hi,

Hi,
Yes I now that with shields things are diferent but I wanna experiment with winding numbers and coil shape all the time to find best spots and learn.Also wire d and compose diferances.This is mainly because I still dont have scope and inductancemeter.
So when coil is exelent without shield whith them the performance will be good.Right.Its hard to change numbers and shape with shields.
So my coils are not for trash!Like I proceed.Just better nulling according to you?
For my first TGS I made 5 coils and finaly I made supreme.So ...

[Fred]

Hi,
Its hard to change numbers and shape with shields....

I don´t think turns should be changed, once you get the right frequency with shields you will only have adjust shape,shiled are not a problem in that case.
You can also adjust the Rx capacitor to correct some imperfection in coil values....
regards,
Fred.

[tiktak]

Hi,

Hi,
I will try!I were thinking that the frequency is set buy number of windings.Now I get your idea.
Thanks