AUTO SENSITIVITY

[stasys]

Gaz what is this?-FBS & BBS machine emit an EM pulse which is a totally different kettle of fish. Gaz FBS and BBS is still the same, air test is very good to see what detector can do and cant, but in the ground can be worst. play with nails and coins,different size. and you will learn what you can pick and what not. if you dont like air test cover with earth. its very good thing to learn your coils and settings. Minelab or other detectors is very simple instrument. good luck in air test Stasys

 

[McDean]

Gaz, all the best mate no offense taken here. This is why I love this forum, I belong to several and always FIND myself coming back here
enjoy your posts as they are informative to all and your advice is well taken... you say you run WITHOUT a threshold? I may give that one a try, I'm not set in my ways yet when it comes to this machine so I like trying new things and different combination of settings...

I know how "airtesting" fbs machines is frowned upon by most, and I understand to an extent but when I get CONSISTENT results... there is atleast something to it but still, mostly for fun and familiarization as these same results will most likely not be duplicated "in the field". Knowing that keeps it all in perspective for me

@sugar... I believe you have the general idea of how sensitivity works and yes a "testbed" would probably be a better way to compare auto to manual because you are introducing the "groundmatrix" factor. in your example "24+3 auto" vs. "27 manual" I believe 27 manual will most likely get more depth by a little, say an inch or so. On the other hand, 27 manual may be more unstable and produce erratic signals (falsing) if this is the case then I would opt for auto... If manual works fine with little to no falsing then I would go with that for the extra depth.

Sensitivity operates on 3 different channels. Auto mode performs an averaging and sets these 3 channels accordingly to give the best depth with emphasis on "stable" operation...

Manual mode allows the user to select and "override" what the detectors processor is suggesting and "locks'' the channels at the highest value therefore allowing more depth but possibly at the cost of stable operation.

If you're going for deeep coins and relics then I would go for the highest sensitivity without falsing... also, if too much falsing, try noise cancel before lowering the sens value. you may find a quieter channel or even change noise channel manually in expert.

If the targets you are hunting are shallow, say within surface to 5" then try lowering sens to reduce power and concentrate on surface stuff so you will not be bothered by deep iron, EMI, etc...

just my two zincs

HH Dean

 

[sugar]

WOW thanks for all that information it is just amazing and i think i will have to keep reading some of these posts until they have sunk in it will be very interesting to try them in the field this is the best site i just keep coming back on here and learning more and more thanks guys i would love to be over the big pond and hunt with some of you it would be awesome happy hunting you guys

 

[McDean]

WOW thanks for all that information it is just amazing and i think i will have to keep reading some of these posts until they have sunk in it will be very interesting to try them in the field this is the best site i just keep coming back on here and learning more and more thanks guys i would love to be over the big pond and hunt with some of you it would be awesome happy hunting you guys

Haha! I too would enjoy a metal detecting foray "across the pond". My oldest find (to date) is dated 1893 an indian LOL over in Europe they find stuff literally 1000's of years old! Awesome stuff...

Its good that you are learning as we all are... you started this ya know LOL there's also a post several pages back about two tone ferrous mode... a very interesting and informative read if you get time.

What part of the country are you in & what are you finding?

HH

 

[sugar]

well i have been working mainly on my own site as it was once owned by the cistercian monks of kirkstaed i have done four years study of the tiles ect on the site and have about two ton of wasters from the kiln and some glazed ridge tiles and better still smaller pieces of glazed floor tiles depicting animals very basic animals 12th 13th century next year we hope a grant will come through to dig the kiln that is there and hopefully get some intact tiles and maybe pottery. to the south of the site i have the old grange run by the cistercian monks it was kind of a farmstead on that land not belonging to me there is a roman villa site nothing left above ground to the north i have five bronze age burials not my land but on one of my fields i have three large humps and have just found a sherd of black exquisite pottery that i need to get checked it is shell like and if it is not modern then i think it will be bucchero pottery made in italy 7000bc and it will be from a funeral urn in the mound ok this brings you almost up to date i have been metal detecting with my etrac 4 months and have found a pommel end 13th 14th century a crusade badge 12 13 century alot of george 111 pennies this week a george 111 cartwheel penny 1797 it is a great big coin and i feel very special to have it i have a really old knife end i mean old but this has to be checked to verify it i have found an excellent foot patten 17th century people used to have this metal thing strapped to their feet to keep them out of the mud on saturday i am going off site to a roman field that has had 12 inches of soil removed for road works so i am hoping to find my first roman coins and artefacts my land has been nighthawked illegal metal detectorist coming on at night so i do not have as many finds as i should have but i am piecing together a story oh i hope i havent bored you by the way i do find worked flint and have one sherd of iron age pottery so it is all to play for and i do need to get deeeep with my etrac lol

 

[Gaz]

.......I've read a couple of articles in one of our detecting magazines over here by Matt Renshaw. He is a detectorist and scientist.
These articles were pretty in depth and he basically explained how FBS works.

We are all on the same side here....we all own ETrac's!!!!!!

Sometimes we can think about things too much. I'm just as guilty!!!

We all know that the Minelab multi frequency machines are deeper than most detectors. That's enough for me personally. I've no need to do any air testing.

It's really just a case of getiing out there and getting some coil time and making a note of any deep finds you get.

Peace out!!!

Gaz.

 

[Jack Flynn]

Remember the busier the ground discriminated out "null" wise the detector will back down in sensitivity. Good targets "accepted" no it won;t back down. I run mine in 28-30 manual ALL the time. I don't get any falsing with the Sunray coils. The only coils I got falsing with were the pro and the SEF's. Just sold my 4th SEF this past week. Sunray all the way for me, I just had to try one last SEF lol.

 

[McDean]

@jack flynn... I never thought of it that way but it does make sense. Just to clarify, more discrimination = lower auto sens because the machine is trying to run as stable as possible. So do you run high manual with not much disc?

@sugar... wow, sounds like you have some great historic sites there! Almost sounds like you need a pulse detector LOL. But the etrac will get deep in the ground, just run sens as high as possible and little disc for sites like that where anything could be a possible amazing find... good luck with your recovery of artefacts and damn nighthawks... make all respectable detectorists look bad :/

Haha, I dug a crushed soda can today that read like a large deep silver... I need some older sites with less modern trash... one can hope LOL

HH all

Dean

 

[Gaz]

....we still dig a fair amount of trash over here as well Dean!!!!......farmers drinking fizzy pop and eating pies throwing the cans and foil out of their tractor windows and ploughing them in!!!!

Gaz.

 

[sugar]

....we still dig a fair amount of trash over here as well Dean!!!!......farmers drinking fizzy pop and eating pies throwing the cans and foil out of their tractor windows and ploughing them in!!!!

Gaz.

haha gaz have you been on the same field as me first three hits yesteday pie foil grrrrrrrrrrrrrrrrr i like to get rid of them though as if i get a bit of trash out there everytime it does help not my back though lol

 

[stasys]

Remember the busier the ground discriminated out "null" wise the detector will back down in sensitivity. Good targets "accepted" no it won;t back down. I run mine in 28-30 manual ALL the time. I don't get any falsing with the Sunray coils. The only coils I got falsing with were the pro and the SEF's. Just sold my 4th SEF this past week. Sunray all the way for me, I just had to try one last SEF lol.

Jack try 1050 and if you get right one you will see how wonderful this coil is, remember all coils the same model are a bit different you can test with tester resistance and you will see. so if you was not lucky with Pro or Sef try another the same coil. I learn with my 1050 coils that all are different and from five, best just two or one- works very smooth and stable, no falsing on hot rocks and etc. all my 1050 with new the same cables so cable problem eliminated . plus my pro coil is crap. if anybody think to buy coil or new detector they should try five, to buy one, with coils is the same. good luck all, and no offensive Gaz

 

[Gaz]

.....non taken Stasys!!

Gaz.