VDI Averaging?

[pa-dirt_nc-sand]

I’ve read that the Nox will sometimes give an average reading when it is over multiple targets. Is this correct?



I dug this gas valve at an old cellar hole. Initially it gave a deep distinct 15 in Field2, after removing a wide 6” plug the signal went to 28. Another 3 or 4 inches down was the gas valve. I’m thinking that I removed an iron target with the initial plug and exposed the hightone target. Is this an example of averaging, iron say -2 plus brass high tone 28 divided by 2 gives an average of close to my 15 initial signal.

I hope this is not the case and I simply removed a shotgun shell headstamp in the plug that ring up around 15. Thoughts?

 

[CladGrabber]

The other day I dug a 15-17 vdi signal. In the plug was 2 rusty nails, 1 nickle and one dime.

 

[pa-dirt_nc-sand]

The other day I dug a 15-17 vdi signal. In the plug was 2 rusty nails, 1 nickle and one dime.

I’m sure there are hundreds of variables taking place here. I know that if recovery is set fast enough and there is enough separation the Nox will give quick individual numbers and tones. But if the recovery is not fast enough or the targets too close or on top of each other, does the program average?

My main reason to ask is that in my hunting areas the ground is littered with iron from 1800’s farm operations and homesites. I hunt with Horseshoe on and the drumming of iron does not stop, it will spike and murmur throughout the hunt. Weak, scratchy, iron tone parallel dragging 8 - 17 VDI’s and tones appear every swing. I have mentally blocked out (subconscious discrimination) these tones unless they sound especially clean and not too loud. Then I swing 4 way and if still steady, deep and clean I dig.

My concern is that any top target hightone keeper (ring, coin, dandy, token, etc) when averaged with iron will fall in this 14-16 range which I see literally every swing. If I dug all I would cover an area the size of a beach blanket in 3 hours and would fill my trash bucket with a veritable plethora of old rusty farm iron.

 

[eman1000]

Pa-dirt, Yes this is true and is true of all VDI detectors that I now of. Some are worse than others (my F22 is not so good) and this is why on old sites you dig those jumpy iffy signals or dig everything if time and energy permits.

Averaging is better than completely masking though!

I'll give you an example you can test at home. The equinox standard coil (I don't have the small coil yet) cannot pass a down the barrel(place a coin next to a nail and sweep from all directions) nail board "Monte" test on penny, dime, quarter (I suspect this is due to the dd coil) however if you hunt with all-metal audio on you can see that most nails alone read between -8 thru +1 or +2 (really old nails will fool you though and chirp higher) Then if you see the vdi jump to a +5 or above there's a possibility that there is a good target next to a nail. (assuming both targets are at the same depth) In your case its quite possible the detector hit the iron first and that is the only vdi you got and you dug solely on the iron vdi. Good thing you checked your hole again because you got a nice relic!

I made a list last night actually and for coin shooting anything that jumps above 14(pulltab) is probably worth digging or investigating on a diff. frequency. I have a few coins that read lower the 3 cent nickel for example was vdi 8/9 and a half dime is so small it reads 18/19 so it wouldn't take much of foil to lower the vdi reading on a coin like that. - If you don't dig it all you won't find gold as gold can easily be below 14.


If your really want to learn more I would read Dankowski's articles on masking as he covers targets at different depths. I question the depths he claims to dig coins at though but I haven't got my hands on a CZ-3D yet so who knows. My Vaq. was slightly deeper than my Equinox I believe but almost to a fault for what kind of hunting I do. I don't really want to dig a can top at 14 inches.

 

[eman1000]

Wow! I just saw your Nova find that's a once in a lifetime find. Did you sell that or do you keep it for major bragging rights

 

[pa-dirt_nc-sand]

Wow! I just saw your Nova find that's a once in a lifetime find. Did you sell that or do you keep it for major bragging rights

Thx! I haven’t sold any of my finds. I lucked out on that hole.

 

[smokeythecat]

Yes, it's true. I was with a friend Saturday and we were digging our "pit". There were good targets and iron in the hole. The 800 became nearly useless and he used a pinpointer, then we switched to my machine which was able to distinguish the good from not so good. The 6" coil will help. Just more $$$ to spend.

 

[pa-dirt_nc-sand]

Pa-dirt, Yes this is true and is true of all VDI detectors that I now of. Some are worse than others (my F22 is not so good) and this is why on old sites you dig those jumpy iffy signals or dig everything if time and energy permits.

Averaging is better than completely masking though!

I'll give you an example you can test at home. The equinox standard coil (I don't have the small coil yet) cannot pass a down the barrel(place a coin next to a nail and sweep from all directions) nail board "Monte" test on penny, dime, quarter (I suspect this is due to the dd coil) however if you hunt with all-metal audio on you can see that most nails alone read between -8 thru +1 or +2 (really old nails will fool you though and chirp higher) Then if you see the vdi jump to a +5 or above there's a possibility that there is a good target next to a nail. (assuming both targets are at the same depth) In your case its quite possible the detector hit the iron first and that is the only vdi you got and you dug solely on the iron vdi. Good thing you checked your hole again because you got a nice relic!

I made a list last night actually and for coin shooting anything that jumps above 14(pulltab) is probably worth digging or investigating on a diff. frequency. I have a few coins that read lower the 3 cent nickel for example was vdi 8/9 and a half dime is so small it reads 18/19 so it wouldn't take much of foil to lower the vdi reading on a coin like that. - If you don't dig it all you won't find gold as gold can easily be below 14.


If your really want to learn more I would read Dankowski's articles on masking as he covers targets at different depths. I question the depths he claims to dig coins at though but I haven't got my hands on a CZ-3D yet so who knows. My Vaq. was slightly deeper than my Equinox I believe but almost to a fault for what kind of hunting I do. I don't really want to dig a can top at 14 inches.

Thx for the info. I’ve never really spent much time with a test garden or air testing. Too much EMI in my neighborhood and everyone including me have dogs with invisible fences. I’ve thought about setting one up in the park woods adjacent to my office. Maybe time to do this and experiment with layered targets and Averaging.

Again I’m sure there are hundreds of variables that come into play here, but I sort of thought that the speed and separation attributes of the Nox would have eliminated averaging.

 

[vferrari]

Many experienced detectorists, especially relic hunters, like to hear it all and run wide open with no disc or notch. I know I do. But this is a case where applying discrimination is actually an advantage. Besides blanking the ID associated with iron, discrimination also helps to prevent VDI averaging. If the discrimination filter identifies iron, then it can eliminate iron not only from ringing up but also from averaging out IDs from multiple/mixed ferrous and non-ferrous targets.

So while I DO normally like to hear the iron, in this situation I would disc iron out up to the desired ID (0, 1 OR 2) and then turn up the threshold. This will cause iron to blank the threshold (so you can "hear" it) but will tend to prevent down averaging of non-ferrous targets. Mixed ferrous or ferrous falses will tend to get clipped if you do this also, which is also tell tale. I have not had a chance to extensively test this on Equinox, but this is EXACTLY how Deus works and is what led Calabash and I to go with the pitch program with iron volume (we can hear the iron but it does not factor into the TID calculation of non-ferrous squeakers). You can still hear the iron but it is no longer involved in processing of the non-ferrous signal and tends to prevent up averaging caused by ferrous wraparound but is more effective on preventing down averaging of non-ferrous targets by nearby ferrous targets. Give it a shot (disc) in your bed-o-nails site and see how it does. Also, if you do get a test garden built, try it there too to see if it works on Equinox.

Smokey and I have been to sites like you describe. Nasty iron infested but also high mineralization. I just go with the Deus and 6 to 7 disc with iron volume in that situation because the Deus just works as I described above at those sites. I am listening for a mid tone squeak or a TID flash in the mid 50's which corresponds to brass on the Deus - and when that happens a button, grommet, or hat number pops out the hole along with a couple nails or hot rocks. Since Deus is so effective in that situation, I have not had a chance to see if using disc on Equinox would similarly prevent down averaging because it usually stays in the truck. In theory it should work though. The small 6-inch Equinox coil helps also by limiting the number of targets that can be under the coil at any one time vs. the stock coil.

That is when I realized there is truly no one size fits all detector. Equinox is pretty close, but still it can benefit from a complimentary detector in some situations.

HTH

 

[eman1000]

Vferrari are you using the small coil on the Equinox yet? Do you think a HF coil or small concentric would work better in the iron. Is this why you are using the Deus in heavy iron?

I'm thinking about picking up a used machine with a nel coil just so I don't have to swap the Equinox coil all the time. The 6" DD seems to me like it would certainly help but I would have liked to seen a small concentric or HF.

 

[vferrari]

Vferrari are you using the small coil on the Equinox yet? Do you think a HF coil or small concentric would work better in the iron. Is this why you are using the Deus in heavy iron?

I'm thinking about picking up a used machine with a nel coil just so I don't have to swap the Equinox coil all the time. The 6" DD seems to me like it would certainly help but I would have liked to seen a small concentric or HF.

I am using the 6-inch coil with Equinox and like it, but I just have more confidence in Deus in those thick iron situations. I use the white Deus HF coil (I prefer the round, Smokey uses the elliptical) we both like to typically run 28 khz in that situation since we are looking for mid conductive relics. I think the X35 Deus coils which can be run up to 26 khz work well too. Concentric coils are great for ferrous IDs and positively IDing bottlecaps and can hit deeper than a DD in clean soil (I like them on my F75). The problem with concentrics is that they lose a lot of sensitivity when used in in highly mineralized soils which is the situation I am typically dealing with at the Virginia sites and since neither Deus nor Equinox have concentric coils as an option, I just don't use them as much anymore.

Got your PM - see my reply.

 

[pa-dirt_nc-sand]

Ok, I discovered that I can swing pretty noise free on my basement up to about sensitivity 18.

Field2, Sensitivity 15, Middle Recovery

Test 1- small iron nails around a Merc. There was no averaging here. Some swings iron masked, some swings 2 way 26.
Test 2- Place a large piece of iron 2” dia thick iron washer next to Merc. This pretty much masked it until the Merc was moved about 4” away then I saw either bouncy averaging, an occasional 26 and masking.

Dropped sensitivity to 6... I was able to separate out the Merc nicely 1-2” away from washer. Amazingly I was still getting a strong 26 signal on the Merc at 4”.

What I learned from this quick test, (with high conductor targets in mind):

-Any little 22 and up signal that can repeat, even if it is a 1/4 swing could be a partially masked coin
-I thought 15 was the lowest I would go on sensitivity around cellar holes, I will now try reswinging a couple at 6 sensitivity really slow at the most logical coin drop areas
-A big piece of iron will wipe out all signals anywhere near it.
-I was not able to recreate the nice small mid tone target I described that started this Averaging thread.

Again there are hundreds of variables here that effect the target. Almost wished I had not done this quick test, ignorance is bliss...

 

[HighVDI]

Am I the only one who gets some up averaging with the Equinox?

 

[vferrari]

I get up averaging on some deep targets.