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The 'Tab' dilemma is more than a simple question to answer.confused smiley

November 26, 2018 12:00PM avatar
Jamie, you asked a good, and very common question. It has been interesting to see how the detector design engineers have dealt with 'Tabs' and visual Target ID from their first adventure into that feature in '83, the 'original' Teknetics, which showed all of us that a lot of those metal detector designers were NOT very active metal detector users. That even goes back to pre-TID days when they were learning more about operating frequencies and how they described their detectors for certain tasks.

In those grand earlier days of TR's and TR-Disc. models we didn't have a problem dealing with common iron nails with the standard TR's, and when they went to TR-Discriminate circuitry in the early '70s it was great at ignoring problem ferrous-based Bottle Caps and lower-conductive foil, and even some of the earlier TR-Discriminators had to have some design revisions because they only adjusted up through smaller-size non-ferrous foil trash. It was the early start-time for those 'Tabs' on cans to replace the use of a manual can opener to pop holes in a can.

I didn't find my first 'Tab' until about April of '72 when I had returned 'home' to Ogden Utah and was detecting an older park. I took a break from detecting on a warm spring day and laid down under a tree for a few minutes. When I went to get up and was pulling my hands out from under my head, my left wrist was cut by something and it turned out to be the first discarded 'Tab' I ever 'found' while out detecting and that curved Beaver-Tail on that Ring-Pull Tab sliced me open pretty good.

Since April of '72 all other 'Tabs' of any variety that I have 'found' were all by way of metal detecting. No more manual 'Tab' encounters. However, like you have been doing, I found it an interesting piece of discarded trash that my straight TR's beeps on, and a cou8ple of TR-Disc. models would knock out Nails, Bottle Caps, most other typical ferrous type trash as well as thin, small Foil from candy and gum wrappers or larger Foil from things like the discarded cigarette packs ... but they didn't adjust high enough to reject the then-new modern trash, those blasted Ring-Pull Tabs.

Soon they seemed to grow in abundance in common use public places like parks, playgrounds and sports fields, picnic areas, and just about anywhere you might find careless people. Manufacturers learned to deal with it by increasing the variable Discrimination so those were rejected. I think they might have simply pulled a Ring-Pull Tab off a can or two and waved it past the coil while determining how they needed to adjust the rejection level to knock them out.

At that pint they did often state that "Pull Tabs" are more conductive than a US Nickel and if you rejected Pull Tabs you would also be rejecting the 5¢ coins as well. Then George Payne got busy working on the CoinComputer design for Teknetics to bring out visual Target ID and soon other detector makers followed to learn how to offer a competitive Target ID model.

Initially, many models showed a small TID numeric indication or the word for the coin. (US coins, naturally, because the CoinComputer and following TID offerings were designed here in the USA, for Coin Hunters mainly to find ... Coins!). So through the years you would see Nickel, Penny, Dime, Quarter, Half and Dollar, or their numeric descriptions of 5¢, 1¢, 10¢, 25¢, 50¢ and $1

At first when they added a description for those annoying pieces of trash they had an indicated 'zone' they labeled "Tabs" or "P. Tabs" that was adjacent to the upper-end 'zone' for the Nickels and it registered upward from there. Looking an my CoinComputer Mark I Ltd., manufactured in 1986, it shows a range for 'P. Tabs' starting down in the upper-end of the 'Nickel' range about where the letter 'E' is in the word 'NICKEL.'

That simply shows that models made 32 years ago had a TID scale that suggested 'Tabs' would be identified in the upper-end of the Nickel ID and on up-scale to be more conductive than the US 5¢ piece. Obviously, the design engineers mush have only used few samples of full-size and fully-opened as if almost flattish original 'Pull Tabs' to determine their scale of acceptance and rejection. It would have been better if they were actual get out in the real world and go detecting type engineers who used a broader assortment of those original-style 'Pull-Tabs' to have real-life specimens of found specimens to Bench Test the various parts and configurations of those Tabs.

Not only were the many Ring-Pull type 'Tabs' made in slightly different sizes and shapes, they were also made of slightly different alloys and that can produce slightly different conductivity levels and thus varying TID read-outs. Even beginning Hobbyists and the Avid Detectorists quickly learned that many Ring-Pull Tabs could be straight or have the Beaver Tail piece misaligned to a different angle, or bent over, or even folded in and through the Ring portion of the Ring-Pull Tabs. Those altered variations of one complete tab created a slightly different conductivity and therefore a different TID than it would if 'straight'.

Then, too, so many of those early Ring-Pull type Tabs had the Beaver Tail portion broken off from the Ring Portion and that doubled up our number of trash targets from just one can! angry smiley When detached, the single Ring portion could have a different TID read-out than the now separated Beaver Tail portion, and the majority of the Beaver Tail pieces, when checked out on-their-on, had a lower level of conductivity and would have Target ID read-out anywhere from slightly below a 5¢ piece on up to almost identical to the 5¢ coin's TID range.

And that's how it was, and still is, when we search any older-use site where the Ring-Pull Tabs were discarded. A broad mix of visual TID, by reference Name or value on the older needle-meter displays or in a range of numeric VDI read-outs on most of the modern TID detectors. The complete Ring-Pull Tabs with both the Ring & Beaver Tail combined in various physical configurations, or the separated Ring portions and Beaver Tail portions, can produce a read-out anywhere from the upper-end Foil range into and through the US Nickel coin range and on up into the 'typical' P. Tab range.

Then beverage can trash got worse.eye popping smiley There were so many complaints from people drinking in a Ring-Pull Tab they had dropped in the can so as not to throw it out, to a lot of people who had issues with them, or their children, encountering those discarded Ring Pulls and getting hurt, just like I did on my first park encounter with one, and they wanted to put a stop to the littering of Ring-Pull Tabs. For a very short while we had the cans with two small spots where we could push in a bigger drink hole and smaller vent hole, but those were annoying. They were replaced by going to a different 'Tab' like we have on most beverage cans here in the USA that have the rectangular-shaped 'Pry-Tab'.

The concept was to eliminate the Ring-Pull Tab that had to be completely pulled off of the can with a Pry-Tab design that was supposed to serve as a 'Stay-Tab' that would be bent up one direction to 'pry' the metal drink-hole open, then fold back out-of-the-way but stay on the can.

That was the engineer's idea. Probably a design by an engineer who had a very short, stubby, blunt nose that isn't bothered by the Pry-Tab. But they end up getting discarded because many folks who have a 'normal' size or bigger nose are annoyed by bumping their nose into that now slightly angled Pry-Tab so they eliminate the annoyance by bending it back-and-forth a few times then looking for a handy piece of grass or dirt to discard it.

Sorry to ramble. but it is an interesting topic and points out why we still encounter so many Pull Tabs of various types because, thanks to visual Target ID. Many people have ignored recovering them and left the trash to continue accumulating. I HAVE Target ID on 10 of my 13 Regular-Use Detectors, but I do NOT use it to make a Dig or No-Dig decision. I simply glance at it to have a better idea of what I might be about to recover. Trash or Keeper, a Beep needs to be recovered if you want to clean a site and also eliminate good-target masking. Plus, glancing at your two piles of 'Tabs', I notice than I could only spot a couple of Pry-Tabs amongst the huge number of older-style Ring-Pull Tabs.

Those modern Pry-Tabs are an even bigger problem for us these days because I have found the bulk of those I have found to produce a numeric VDI read-out almost identical to the US Nickel coin, or read up-scale into the 'P. Tab' range where many larger Gold Rings also display as well as many Silver pieces of jewelry and even up-scale beyond that. I have one very 'average-looking' Pry-Tab that produced a 'lock-on' ID that matches most modern US Zinc Cents, which is also where most Indian Head cents read and some of the earlier date Wheat-back Cents from 1909 to about 1920 might also display.


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Jamie
Yes I’m bored, unable to detect because of the frozen ground.
Yes, winter seems to have arrived and looking ahead we might not have detectable weather until mid-February to the first of March. Time to dig out some of my favorite old movies from when they used to make good westerns or comedy.


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Jamie
I have been bench testing at the kitchen table. Playing with the classic ID, and the III SL. I have a pile of pull tabs that I keep for testing. Also to keep track of how many I pull from one location until gold or a buffalo appears.
Good for you at being determined to recover the 'Tabs' as that will help lead to some successful days afield.


Quote
Jamie
I decided to scan every tab on my ID to see where they registered at. The small pile in the picture all hit at 5 cents, but with a small target bounce.
I'm curious what you mean by 'small target bounce' and figure that means a left-side or down-scale 'bounce.' I noticed in your photos that it looks like a majority of your 'Tabs' are the Ring portion alone. I do see quite a few combined samples with the Ring and Beaver Tail at differing angles, or with the Beaver Tail folded through the Ring portion, etc.

What I didn't easily see was an equal number of separated Beaver Tail portions to come close to matching the Ring portions. Usually when people get bored and tinker around folding the two parts back-and-forth to break them apart they dispose of them in the same direction, thus the Beaver Tails should be in a similar area with the Rink parts of the 'Tab.'

If your 'bounce' is to the left for a lower-conductive reading, I would think that might be associated with:

• A separated Beaver Tail

• A combined Ring and Beaver Tail 'Tab'

With the Beaver Tail having more influence on the 5¢ display zone read-out, that might be causing the 'bounce.'


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Jamie
The larger top pile all nailed pretty solid on the pull tab block to the right of nickels.
And as I mentioned, most Ring-Pull Tabs did just that, show a higher scale/more conductive response than the US Nickel coin.


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Jamie
All the nickels I tested were a solid ID with the ghost flash.
By 'ghost flash' which direction is it flashing, and how was the Nickel coin presented? Were you using the standard 8" Concentric coil and in the Discriminate mode? Was the Nickel held 'flat-to-the-coil' position and moved past the coil at about 3" to 5" distance?

I just grabbed my modified Classic ID and check it out for a 'flash' with a couple of US 5¢ 'nickels' and it locks on very solid. I mean very solid without a flash or flicker with a proper GB. Since my unit is modified I have a manual Threshold control as well as a manual 1-turn Ground Balance so I double checked my 5¢ read-out at GB extremes. On my unit, with a very mineralized rock I use in evaluations that is just about softball size and on some detectors produced a ground phase read-out of '86+,' my modified Classic ID GB's with the control pointer at almost a 3 o'clock position.

If I increase the GB turning it fully clockwise and check the 5¢ coin at 3" to 7" it stays solid, even if moved across the coil just slightly off from center-axis. When I turn the GB control fully negative, or counter-clockwise, it still stays a very solid lock-on except maybe 2 out of a dozen passes when off-center and about 6" to 8" from the coil, and I am using my 5½" Concentric 'Ferret' coil. On those very few waves in the bench test it showed a 5¢ segment lock-on but with a very brief 'flash' to the right, or upscale from the 5¢ block.

So I would think that if you are getting too much 'flashing' from the 5¢ ID segment and your coin is positioned flat-to-the-coil and worked about 3" to 5" away from the coil, then your unit might need to be recalibrated for proper Target ID


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Jamie
My question is how consistent should I expect the pulltabs to be in the ground on the ID?
That would depend upon their orientation to the coil, their depth from the coil, and the severity of the ground mineral environment you are hunting. Also remember that all metal targets might have their own 'air test' TID response that might still hold similar behavior in the ground, but many do not. 'Tabs' have their open 'ring' shape and are made of a higher-conductive metal mix, but they are also thinner than most coins.

Target detection relies on several factors, such as the operating frequency. Search coil size, shape and type. Sensitivity and/or Gain associated with the settings used, and the metal target's size (diameter), shape and we can't forget thickness. The Beaver Tail sections are very thin. Most of the Ring portions or modern Pry Tabs are also thinner than most coins and that, alone, can have a bad influence on the generated EMF on the target.

Combined with a ground mineral signal and the detector's circuitry audio processing, we can often have thinner-shaped targets, as well as others, respond when in the ground with a higher-than normal Target ID read-out. Sometimes maybe negative, but I have noticed more false TID responses reading higher when in the ground but at a 'normal' read-out once removed from the ground.


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Jamie
Now keep in mind, I want to dig them all up. I’m not trying to ignore them. Just trying to get a feel for the machine. It’s going to be a long winter.
All targets can respond with a 'proper' TID, or have a lower-than-normal or a higher-than-normal visual and audio response. Nothing is going to be 'perfect' so even when using my more sophisticated models with different Audio Tone ID or the different visual Target ID responses, I might glance at the display or listen to the audio tone information, but in the end I simply hunt with my preferred settings, then recover all audio hits and take a look at what I just found.

By the way, while I enjoy all of the models I have in my working detector outfit, my modified White's Classic ID is one that I rely on in all make and model comparisons, like my Tesoro Bandido II µMAX and Nokta CoRe, to evaluate their performance afield in a wide range of hunting environments. Those are my three 'performance comparison models' and a lot of the competition out there falls short on matching what these three units can do.

In closing this lengthy reply I will add one final comment about 'Tabs' and 'Target ID.' In 1994 I took a trip down to Prescott Arizona to give a week long class on Recreational metal Detecting at Yavapai College. On the last day of 'field time' we met at a Prescott park that was trashy, and before the last two days I went there very early and used a couple of detectors to hunt as much as possible and recover as many 'Tabs' as possible just to demonstrate how annoying they could be.

I gathered as many 'Tabs' as I could including completed Ring-Pull Tabs, separate Ring portions and Beaver Tail portions, and a good number of the newer Pry Tabs. I used my White's 5900 Di Pro SL that had a very accurate free-floating needle meter. I also had some little pricing tags and I sat down and used EVERY Tab or Tab portion and started to check them all and separated them in order of their conductivity. When finished, I had separated all 'Tabs' in order from reading in the upper Foil range into and through the Nickel range, all across the P. Tab range and into the zone just higher than 'Tabs' on the display to indicate at the start of the Screw Cap range.

That resulted in 27 Tabs and Tab-parts with different conductivity levels. And with the newer Pry-Tab that reads like a Screw Cap or Zinc Cent, that means there are just way too many different reading hunks of Tab Trash to be too concerned about. I think I'd spend my wintry time doing research for 2019 hunt sites instead of 'Tab Tinkering' especially since you're going to be recovering them anyway.

Monte

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Subject Author Views Posted

Pull tab question

Jamie 98 November 25, 2018 11:23AM

I've found that that the pull tab range of conductivity is sometimes a great targetthumbs up

Hombre 57 December 06, 2018 04:48PM

Re: Pull tab question

RickUK 45 December 04, 2018 11:18PM

The NOTCH and Schemes for Avoiding Pull Tabs / Square Tabs

Rich (Utah) 53 December 04, 2018 09:38PM

The 'Tab' dilemma is more than a simple question to answer.confused smiley

Monte 84 November 26, 2018 12:00PM

Re: The 'Tab' dilemma is more than a simple question to answer.confused smiley

Jamie 53 December 02, 2018 06:36PM

I will dig those tabs and stop testing.thumbs up

Monte 70 December 03, 2018 09:31AM



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