Whites TDI Classroom

Hi All,

Usually, I focus on the technical aspects of any new detector and what a person might expect, but this post is a little different. I hope you will bear with me.

Did you ever wonder why information about a new detector almost never is released in any form before the official release date??? Well, the answer is simple, nobody can get it right and who knows what is really said.

It is sad that things get distorted or not everyone can be let in on what is new or coming out in a few weeks or months. Obviously, manufacturers are concerned about how new ideas will be accepted and of course, how any new detector will affect sales of present models. That even holds true for most things including totally different items such as cars.

I have known about the SL for quite some time partly because of some ideas I had were used in the new design. At one time a target date was set and after that date I was told one could talk about the new machine. Well, that date came and went without the new detector being introduced. Everyone was wanting this detector to be as good as it could given its features and new ideas.

A few units were out in the field being tested, looking for any quirks or little things that needed to be addressed before the new unit went into production. Of course, some people do get to see this new detector if they happen to hunt with one of the people testing the production unit.

So, regardless of how hard a company tries, there is always some word that manages to surface.

When I got the final word of the design that the SL was going to be a lower priced model that had the advantage of being lighter and quieter, I personally thought it was a great concept. In this day and age, when has anyone seen anything built that has a couple of new features, most of the depth of its big brothers, yet is cheaper?

Personally, I thought Whites was doing a great favor to its followers and any potential new owners for that matter. At no time did I ever hear or read anything that would indicate this new detector was the next major advancement in the generation of the TDI line.

What was hinted before the official introduction was this unit had a couple of great features that I felt would make new potential owners happy and those were a very stable threshold and the possibility of improved sensitivity to small gold. To be honest, I wasn't sure whether Whites was going to add the feature that could give better results on the really small stuff. This feature seemed to work but hadn't gotten that long of a test. Fortunately, I had more experience with using it and I felt it was stable.

Now, I personally thought Whites was doing a great favor to the public by adding two great features on this lower priced unit. Those two features, as mentioned, are the stable threshold and this improvement in the detection of small gold. Both are clearly novel on most PI's and non existent on anything even close in competition price wise.

Unfortunately, it appears some people aren't happy that this new detector that sells for hundreds less than the Pro model because it doesn't have the Pro features. Because this detector was never designed to compete with the TDI pro and to keep the cost down, the extras that made the Pro, the Pro model were not added. I would think that Common Sense 101 should prevail but it doesn't.

The SL is a very unique simple to use PI that has a very pleasant threshold. It can detect smaller gold than its big brothers. It doesn't have automatic ground balance or any other similar feature, which was something others were demanding.

Now, for the record, I have used the TDI or its predecessor across a large area of this country and I have never found anywhere where I couldn't ground balance the detector. It might be touchier in some places than others, but I could always get the job done. Also, because of the unique technique of how targets could be separated by adjusting the GB control, this automatic feature didn't make sense at this time anyway.

The ground in OZ is dramatically worse than anywhere we can find here in the US and it was found the TDI would work well even over there but the vernier GB did make things easier. So, the Pro was designed mainly for those in OZ wanting a new detector. Auto GB has its down side since there is always the possibility very weak targets can be tracked out and be missed. A ground grab feature might be nice but engineering time and parts could significantly increase the cost, so it had to be evaluated as to whether adding this feature was worth it. Since the GB isn't that difficult in most places, such an addition was not considered a top priority. Now, this doesn't mean it isn't being considered but it was thought the features already added were bigger improvements.

What this post is trying to point out is the fact that no matter what White's or what any company does for that matter, it will never please everyone. What is sad is with the internet so easy to access and to post on, people who are not personally happy seem to have to take their best shot. It is even worse if they feel they should have been in the loop and weren't. That is truly sad but is going to happen.

So, what you hear good or bad, I strongly urge anyone considering the purchase of the SL to try to visit their local dealer and check it out and, if possible, compare it to the other TDI models. It is best to try to see if it meets your needs or not.

Metal detectors are sort of like wives in the fact, we all have different ideas of what makes us happy. Also, keep in mind we should also consider very carefully what is acceptable and finally, what can be tolerated. If there are issues that fall out of the key zones, problems will most likely occur that can lead to not being happy with a decision.

Now having said that, I certainly do not want anyone making a decision about the SL because of the fact that I have said I like it or reject it because someone else is truly disappointed and doesn't recommend it.

When I hear conflicting remarks I always go back and think about the picking of a wife. What some people are happy with would drive me nuts just like what I may like may not be pleasing to someone else. We are all human and think and feel differently about things and whether it is a wife or a detector we will never agree all the time.

I hope this post makes sense and if you wander around the net looking for answers, will better understand the why's behind this posting.

Reg

Reg,

Thanks for your comments. I think you are spot on correct. It is impossible to please everybody all of the time. I have read a lot of whining from a certain individual who is complaining because of his potential lack of financial gain with this new detector. I guess he expected White's to cater to his business needs. What a selfish motive!

I am still learning my TDI, ever so slowly. Reg, I always appreciate your insights and knowledge about the TDI line of detectors. I hope, especially for White's sake, that the SL is a success and that many people find gold, relics and coins with it!! I am excited to read further reports of its performance as they develop.

---

White's IDX Pro, White's TDI SL

Reg, I was with you before you drew a parallel with the relationships we have to deal with regarding Wives and I'll add Girlfriends as well. No two Wives Ground Balance A like that's for sure. The Truth about wives and even Girlfriends and the Affect they have on Men can be answered by watching the Jerry Springer Show where they all seem to share that tempestuous pugnacious emotional drama queen similarities. Us Guys are definitely Easier Going and More intense in other areas of life seeking stability and happiness in our metal detecting without criticism from the significant others.

Getting back to the MORE Stable Subject of the New TDI SL. Do you think that Dan's new circuit, much quieter is going to have an impact on the TDI Series going forward? Have you had a chance to A/B the Pro and the SL on any sort of Test Garden using at least a High Conductor or a Low Conductor?

Would it make sense to shoe horn the NEW TDI SL Circuit into a Water Submersible Housing? As it is now, Garrett's Infinium is the only WATER Submersible Super PI engineered for Prospecting but as you know lacks a Ground Balance Control and Sensitivity Control.

Regarding Ground Tracking....I don't see the need. I caution the use of Ground Tracking in many models because EMI can throw off the circuit as well as an area rich in debris of all sizes. UNLESS the ground changes are constant as in Beach Hunting down to the Surf Line, I tend to lock the tracking to ensure accuracy of ground balance when the ground is more homogeneous. Also, a CLEAN Razor Sharp Threshold is the KEY to monitoring your tuning proficiency. I've used the Minelab 2200 V2s which have
automatic ground tracking but there is always a risk to go into automatic mode. Take the GMT.... you can run it in automatic, lock it and use Ground GRAB also found in the new White's MXT PRO but in the case of the GMT, you have a PLUS and MINUS
over-ride for certain difficult mineralization situations. So Automatic isn't always Automatically the BEST. I found this out with the Minelab Explorer Series.... best to take it off Automatic and Optimize it yourself According to the Conditions.

Concerning my Relationship with my Wife Jen (Jenster, Jenzilla), there is NO Automatic Mode in dealing with her. I have to be very careful in my responses and Tone.... it is a measured response in my attitude toward her. Putting myself on
Semi or Fully Automatic Mode may cause me to IGNORE her and then I'm cooked. I have learned throughout my relationship-marriage to deal with the changing moods like I deal with the changing ground mineralization. Automatic just doesn't achieve Maximum Performance whether its your Metal Detector, Your Wife, Your Girlfriend or the Cruise Control on your Vehicle... you can't just SET it and Forget It.

But Reg, your points are very well taken.

Hi dbsmokey,

I wasn't targeting anyone or any place in particular but when any new detector comes out, lines are drawn in the sand with some on one side complaining and others on the opposite praising the benefits. This human characteristic that we have to attack or defend is tough to understand.

I point out differences in price between models or detectors in genera and I have been accused of picking on a different detector. On the opposite side of the coin, some don't realize differences are related to costs.

Getting back to what can be read across the net, what I refer to is not just about the SL and the TDI, but if you look you will find it about other similar models built by other companies.

I wish I had a way to explain the difficulties in developing any new model or idea and why it makes a difference or not. People want certain features or designs and they want them now. The sad part is some things are extremely difficult to design or change much.

Some features are simply not needed but are a nice convenience. What is worse is the fact people have become dependent on features, that I feel shouldn't be used.

On another forum I saw where a guy was asking for the best "program" for nugget shooting. Whoa, does anyone really know how a "program" can or does work? The simple best design is the one that uses the basic techniques. Adding any other feature can and usually will have some negative side effect.

On the TDI or the SL, the single tone feature is a perfect example. Select low conductor and most gold we normally find will be detected. At the same time, a lot of the iron junk can be ignored. This sounds like the perfect solution until we realize that a large nugget may simply be ignored and then people get mad especially if it happens to them. This is why I always recommend searching an area more than once and adjust the detector to cover all bases, or in this case, all sizes of gold.

On the SL, one complaint already surfacing is the fact this detector acts a little different than the regular TDI if the GB is off some. It is very possible to get a usually non repeatable false signal if the GB control is set too low. Tweak the GB and bingo, it is gone.

Initially, when I heard it I thought I had a weak deep target, but clearing a little of the surface dirt would cause the same signal to disappear. After a couple of times, I realize this odd target signal wasn't real and most likely cause by the ground conditions.

Now, such possible conditions should be considered normal and could happen. Thinking is required when using a detector and generally this becomes more important in areas where conditions are worse such as in gold producing areas because of all the variations in hotrocks as well changes in ground conditions.

If any of the issues I mentioned seem too complicated, well, don't expect to find much even with the best of detectors. Regardless of what one might think, those with the most knowledge and experience will be the "luckiest". Spending time with a detector experimenting and practicing does add to that knowledge and experience data base.

Reg

Hi au4greg,

I am assuming the circuit you are referring to by Dan, ie, the noise reduction design will go forward. To brief you in on this design, the original concept was a little different but not by much at all. How do I know, well it was my idea. The theory of why or how it might work was something I came up with and implemented it in my detector originally to begin with. The noise reduction was dramatic. Even I was impressed with how well it worked.

Now, to minimize parts, I attacked the key channel causing most of the noise. The idea being minimize the noise and not touch the other channel would give the best of both worlds. By this I mean, if you turn off the GB, the depth capability increases and in some cases dramatically. My initial design basically switched to the non GB mode on very deep targets. So, suddenly I had an increase in depth as well as noise reduction.

Now,this sounds perfect but like all designs, for every action, there is a reaction. What happened was a very slight error in the GB would also occur and could easily translate into a false signal much like what happens on the SL if the GB isn't adjusted high enough. So, as a solution, someone, probably Dan simply added my idea to the second channel and it balanced things out, but at the expense of the additional depth. Again, for every action there is a reaction.

As an additional note, I have added another trick and that feature reduces the noise base which in effect reduces the offset I get on my initial design to the point that it appears to work now without the error in GB.

Now, getting back to your question as to whether this mod might make its way to the TDI and maybe the Pro? That is a question that only Whites can answer. The pc board in the TDI and Pro board presently found in the models already produced would have to be modified, for this too occur and this takes engineering time and energy. Do I expect this to happen in the future, yes, but I have no idea when. Could it be an add on? Not likely because of the nature of the design. So, present owners shouldn't be expecting that their units could be modified.

I wouldn't get discouraged though because there is always something on the horizon and one thing I am thinking about is something that would do basically the same, reduce the noise and have other benefits and would be a form of add on. If I wasn't so lazy, it would have done by now.

Now, going on to the test feature I haven't spent a lot of time comparing the SL and the TDI or Pro type model. Please keep in mind that I only have one TDI that remains stock. All other units I have whether they be a modified GS 5 or TDI have been modified, so comparing or testing would be further complicated.

Now, given my excuse for not comparing, theory says that lower power into the coil the less potential depth. Just how much probably could be calculated, but I haven't tried. How much difference would I expect? Well, given the fact the depth loss or gain is not linear by any means, I suspect it won't be much. This depth loss is probably also coil dependent, meaning if the 7 1/2" coil is compared on both, the depth loss would be even less.

Personally, I have seen greater depth losses because of improper setting of the frequency control than what I expect to find between the two models if that makes sense. Most people do not realize just how important this can be. I have also found that on the present TDI models, I can adjust the gain back to between 6 and max and actually get greater depth at times.

So, an answer isn't going to be reliable or consistent especially considering the fact, the threshold is so quiet, it can be difficult to set the freq for the best setting on the SL. Given all things being equal, one might expect to see maybe a 10% or maybe a little more depth loss. Since a minor error in the freq control can cause a far greater depth loss than that, all bets are off in coming up with anything consistent.

Reg