WHites Pulse Scan TDi for Aust conditions??

[OzzyGold]

Anybody out there able to give me some real info on their use of the TDI?

Digger Bob and Sierra put in their bit in Whites Field manual for the TDI, anyone else got anything to say, negatives or positives, especially of you have used it in Aust?

Still using yours Digger Bob or Sierra?

 

[snakejim]

As I understand it, Eric Foster the main designer of the TDI; is in Australia or will be shortly. He is there to address a change he might make to the unit for Australia's conditions. Seems there was a question about it's ability to handle areas of extreme mineralization.
Hope this helps.

 

[Digger Bob]

You bet I'm still using it! In fact, if I had my camera with me I'd post a pic of the nuggets I got just last weekend. And I got a small one in Nevada weekend before last.
Here's some observations since doing that little blurb in the manual.

The stock loop is great for small AND large nuggets at depth. BUT it is constantly getting hung up in sticks and stones due to the open spider web design. Get the solid loop cover for it. Most of my hunting is done now with the new "Digger" loop, 9x14. Better ground coverage, same depth and sensitivity, solid design, eliptical for tight places. The "Jimmy' loop is also good for the tighter places and smaller nuggets.

The threshold is wobbly over a gain of 6. If you can hunt slow enough and learn to listen, you can work with it up to 12 but it takes some practice.

I tried hunting in the "All" position this weekend. Iron targets everywhere. Switched back to "Low" and they disapeared for the most part. I dug a few small pieces of iron that sounded good. Had I been using my Minelab, I'd still be there checking those targets. It's not perfect but it sure works well under some circumstances. The nuggets sounded off loud and clear.

For hunting hillsides you'd better hip or chest mount it unless you have arms like Popeye. It gets heavy real fast.

I have used it in the worse ground I know of here in California, including the nasty stuff down in Mariposa. It simply does not see or hear that ground if you set it up right. Australian ground is a different kind of mineralization. That's why Eric is down there trying to come up with a way to deal with it.

There are the rare nugget that it won't hear. I discovered that in Mariposa too. If it's light, airy, spongy, very irregular, sometimes the pulse just bends around it instead of "bouncing off and back". But Minelabs have the same problem too. It's a unique feature to PI's. I did find however, that I can get a response from those nuggets with the Jimmy loop that I couldnt' get with the stock loop.

That's about all for now. Oh, they finally have a car charger for it. The batteries are good for 12 to 14 hours, more than a day. More loops are coming designed especially for it. But any Minelab, Coiltek, or Nuggetfinder MONO loop will work. I used a Nuggetfinder 16" round for a bit in Nevada and I could hear every deep signal the Minelab could, for the ones that I checked.

Ok, now that's it for now.

Digger Bob

 

[David]

That's is a great outstanding report Digger Bob! Your Digger Loop is 9x14, what size is the Jimmy Loop ?

I have never run a TDI. It sounds like it does not have Auto Tracking Ground Balance but instead a type of Manual GB. I do not know how that works, but is the TDI time consuming and/or hard to keep adjusting the GB manually in tune all of the time, or not ?

Why is there no Auto Tracking GB on the TDI, especially when Whites already does have very good Auto Tracking GB technology on the MXT and GMT ?

The TDI seems to run like the SD 2100 with no Auto Tracking GB, or not ?

Thank you!

 

[Digger Bob]

Thanks Dave,

To answer your questions;

The Jimmy loop is 5x9, dual field, just like the stock loop.

There is no Auto ground balance on the TDI. It isn't needed. If there is any amount of mineralization, it will always balance between 8 and 9 manually. It's very much like the old 2100. Once you set it, it pretty much is set for the day. If mineralization is minimal, you can turn the ground balance off and let the pulse smooth out any variances. You will get more depth this way but all targets sound the same.

You can find MUCH more detailed information at this site. http://tdi.invisionplus.net/index.php?mforum=tdi&showforum=3
We have the experts in the field contributing, including Eric Foster. And Reg is a wealth of knowledge on the technical side. Scroll down through some of the older posts and you can find all your questions anwered.

Digger Bob

 

[OzzyGold]

Thanks for the feedback Digger Bob et al,
very interesting. I suppose it all comes down to how different the Aust mineralisation is and its affect on the TDI operating. The less depth has me concerned but then if things are really bad you have to adjust the Minelabs a lot to keep stable anyway, thus losing depth? We have some very bad ground to work with here.

I have a 10X5 Nugget Finder Mono, I imagine that would be very similar to your Jimmy Loop? What do you use for a larger coil?

regards
OzzyGold

 

[Digger Bob]

Since I have and use both the TDI and Minelab I can say with a certain confidence that raw depth is the only thing Minelab has over the TDI. And over here, that depth is about 25% less. However, every poll I've seen made of successful nugget hunters asking "What's the average depth most of you nuggets are found?", the answer is 6 inches. Some deeper, some shallower, but the average is about 6 inches. That being the case, 75% of the gold that can be detected is no deeper than 6 inches. That is well within the range of the TDI with any loop. And if you are in an area known for large nuggets at depth, then you can go with a larger loop.
So, when you combine all the other positive factors over the Minelab; cost, weight, balance,ease of operation, hip mountable, external speaker, 2 Li Ion batteries, wide selection of loops, etc., the factors begin weighing in favor of the TDI. Now if they could just come up with a way to deal with that nasty ground over there...

Yes, your 10X5 Nuggetfinder would be very similar to the Jimmy loop. However, it's a straight mono whereas the Jimmy is a dual field configuration. The only larger loop I have used extensivly is the 9x14 Digger loop. I have larger Coiltek loops but haven't used them yet.

Digger Bob

 

[David]

Great report again Bob!! Yes that is a Minelab drawback. Great machine as I have a GP 3000 BUT yes it is too cumbersome and heavy. I now am looking at a TDI or a Infinium LS for second prospecting unit. They are much better at being more compact self-contained, lighter-weight, more manouverable(hipmount), quick to get going, and grab & run units than the Minelabs, with a small sacrifice in performance.

Do you yourself know or did you hear from someone else how the TDI compares with the Infinium LS, only in performance(depth-sensitivity) wise, nothing else?? Thank you.

P.S. Is your 9x14 Digger Loop a Dual-Field also?
Is a Dual-Field better than a regular Mono?
Finally, can a TDI Dual-Field Loop be used on a Minelab PI?

 

[OzzyGold]

I believe the dual field is a problem over here due to the mineralisation, probably too much with two coils, be hard to stabilise threshold? Do you know of any users in Aust?
Regards

 

[Digger Bob]

I would tend to think the dual field would be better over there because it acts very much like a DD loop. It is literally two loops combined; a larger one (for depth) wrapped around a smaller one (for smaller targets.)
No, I don't know anyone over in Oz who has one yet.

Digger Bob

 

[David]

"Now if they could just come up with a way to deal with that nasty ground over there..."

You are the second person that said the TDI does not handle Aussie conditions and I have heard other complaints about the Goldscan 5 in Australia also. The TDI has a slight advantage in sensitity but the waterproof Infinium has Tracking. I would buy a Garrett Infinium LS(one made in the last 2 years with the Aussie mods) over a TDI now looking at it from all angles. The Infinium having the the two 10x14" DD and Mono will be sufficient coils with the smaller ones. My choice is the Infinium LS for a second unit. It also handles bad ground and hotrocks. Steve Hershbach said The Infinium is equivalent to a Minelab Pulse Machine with at 11" DD in one of his articles. So that is fine with me.

 

[Digger Bob]

I was going to sugest contacting Steve Hershbach and ask him about the differences. He's the only one I know of that has used both and could give a fair side by side comparison. I've never used an Infinium but have heard a lot about it. I, of course, am a bit biased but I wasn't aware that they had made Oz mods for it. Without that, I think the TDI is a better machine. With that, who knows? Have you had any contact with someone "over there" who has used an Infinium in the nasty ground gold fields? That would be informative. Alaskan ground for the most part is very mild. Oh, did I mention the TDI doesn't see hot rocks? And that is immune to EDI interference? But it does like to screw up Minelabs if you get too close.

Digger Bob

 

[steve herschbach]

That the Infinium did about as well as an SD 2100 with an 11" DD coil on quarter ounce to 2 ounce type gold in our moderately mineralized ground at Moore Creek. The ground is not that hot but the basalt cobbles are bad enough that Minelabs up until the GPX hit on them, as do the Infinium and TDI. But I also noted that if you just put a bigger coil on the Minelab it easily pulled ahead.

I doubt the Infinium would fare much better than the TDI in Oz. I just got a new Infinium and of course still have the TDI. The ONLY reason I got another Infinium is it is waterproof. In general I prefer the TDI as it is more adjustable. The Infinium and the TDI are pretty close for performance in my ground, but again, I can cheat and put a larger coil on my TDI than I can get for my Infinium. The fact is that the Infinium seems to have found a popular niche as a water machine but few people seem to be using it for nugget hunting these days.

Since Eric is headed over there I think it is safe to say White's thinks the TDI can be improved for Australian conditions. So let's sit back and see what he comes up with. I know I'd like more range on the ground balance control. In some places I just tun out of adjustment and I would not be surprised if that were a problem in Oz.

I like my TDI and Infinium but I have to say if I were headed down under tomorrow I'd be packing a GPX-4500. With the current price of gold I can pay for one pretty fast.

Steve Herschbach

 

[ivanll]

The Infinium LS is use-full for prospecting in Au, but it does seem a wee bit short on ground balancing adjustment in many areas, even with the Au

mods in place for oz condition the first of which is our household power supply 240v 50Hz
Some with vested interests excuses this as user inexperience, but invitation have been extended for them to come and share their method, so fare the

invitations have had no takers.
The older coils with flat inner coil wires are prone to external electrical interferences and so have a tendency to plays havoc with the audio threshold

when beach hunting on popular beaches near build up areas.
Same coils works fine on gold fields away from electrical interferences, provided one is not in an area with "ground balancing issues".
Later coils with the new round coil wires are fare less prone to outside electrical interferences and so allows a near perfectly steady audio threshold

when beach hunting but still have issues in the bad ground areas.

Above info is based on my Infinium LS + coil set-up in areas and condition in which it has been used.

TDI's are imported and used in Au, a near new one was for sale on eBay just last week.

ivanll