Jim in Idaho

"Of course Gen 1 does not have a vernier GB, perhaps because the GB is not to touchy (critical) in finding the quiet GB position. Having not used a SL, I am guessing here." Actually, the Pro version of the Gen 1 (made for Australian use) has a "fine adjust" control. And, the more GB you dial in, the less sensitive it is. In effect, you are telling your detector to ignore a greater range of signals. The less GB you can use, along with having a stable machine, the better. Jim

The problem with the TDI SL, and I don't know if it exists with the other TDI models, is that the GB "range" is fairly wide. Much moreso than VLF units. I installed vernier controls on mine, so I could easily obtain a GB setting that just "barely" quiets my detector. I think it makes a difference. Jim

I have Reg's chart taped to the bottom of my SL. If I haven't used the SL for awhile, it's good to be able to refer to it. Jim

The problem can have many causes. Shape, porosity, alloys, etc. This problem is why ML's have so many adjustments, including variable timing. To find everything you may have to go over the same ground multiple times, with varied settings, but that beats leaving gold behind, though some will still not be indicated. Jim

Yes...the TDI manifests the same issue, and to a greater degree. Jim

I should probably test the DC resistance of this ML coil, and also the inductance, and see how those specs compare to a different mono coil made for the TDI. However, the Sadie is not made specifically, for the TDI, and it works great on them, so maybe it doesn't matter. Jim

Yes...it's been known for a long time that you can use ML coils on TDI's, but not the other way around. Jim

Jim, before you go that trouble, let's wait and let the snow and ice melt around here, and let me do some testing with this coil. Then that might make an interesting comparison. There must be some electrical difference between them, or why the different labels? Unless it was done just on the ones they eventually exported to the states. Maybe initially they were included in a package deal or something on a GPX 4500, or other, and had the ML label, and then they started the TDI labels for some reason. No way to know. I'll keep you updated, in any case. Jim

I don't see mine listed. This coil, is black, with a white Razorback label. The label says Razorback....Professional ML Series, and below that "5 x 10". Jim

Many thanks! I hadn't noticed it was in the chart. I'll go back and take a look. If it's close to Sadie performance, I'm going to be glad I bought it. I really like the narrow profile. Great for hunting in the rocks and brush. Jim

Karelian, I bought a Razorback 10 x 5 this past winter. Have you done any testing on that coil? I'm curious to see how it does, but my local ground is covered with "global warming" this morning. Jim

I'd be willing to bet sizeable money that Mike meant to type .5gram, and not .5 grain when he did that test result. The chance of any TDI seeing any gold as small as .5 grain at 10" is somewhere between slim and zero...LOL Jim

Interesting. I've never seen a poor test result, on any of the TDI models, that showed the Sadie being anything but near the top of the list for small gold, and one of the best at moderate depth. Have no idea what Mj is talking about. I know my experience, and testing, of the MJ 5 x 9 was disappointing. So much so that I sold it. I do use a MJ 8 x 11, however, which I have found superior to the 12" DF with my machines. Maybe MJ never tested the TDI SL with a 16v battery pack. Jim

Yes, Bob..Mike (karelian) down in Australia has done some great tests. My results are right inline with his. And, I do have the 16v+ battery pack. I bought my first one, but then built another. I've also done the circuit mods...both #1 for sweep speed, and #2 for sensitivity. There is a 3rd also, which I still plan on doing, which also increases the sensitivity. I also added vernier control knobs to mine, on both the ground Balance, and Threshold. That makes it easy to precisely adjust both. Jim

I doubt you'll find many .4 grain nuggets with any TDI. My modified TDI SL is decent on 1 grain-sized nuggets, but a .4 grain would have to be nearly in contact with the coil, I'd imagine. Jim

I've got one of Whites original TM808's, with Cave Mode. But, I'm always looking to improve, like all of us. I have great respect for Steve H., when it comes to detector capability. Jim

Hey Steve...in your humble opinion, is this going to offer significant improvement on the TM808? Jim

Got that right. Same here in Idaho. First prospecting/camping trip planned for early to mid April, though. Jim

That is a nifty find, for sure. If I'd found that, it would have made my day. Jim

Definitely a lock ring of some kind, as Chuck said, but not for a hex nut. Some sort of "specialized" 8-sided nut. Kinda weird. Jim

I dropped my membership 2 years ago. Thought the whole thing was a waste of my time and money, and the outing I went to was a joke. Not at all surprised...only that it lasted this long. Jim

You might watch this video from Jeff Williams. He talks about chrysicolla and skarns, and gold. The stuff he shows looks just like yours. Jim

I'd be crushing some of that reddish material below the blue. Might be a "skarn" and could hold gold. Jim

Some people??? seems, to me, we have a bunch of them. Jim

On my TDI SL, the threshold slowly gets louder as the batteries decline. Have to readjust as I detect. Just food for thought. Jim