Thoughts On The TDI SL ?

[tboykin]

34 minutes ago, Hard Prospector said:

Tom,

I've been using the TDI SL for several years, have found my share of nice nuggets and love the machine.....

Rob, thank you for the suggestions. The SL can safely handle up to 16 volts, and I've tested it with higher voltage batteries with a good increase in performance.

The issue with an 8usec delay is choosing a coil that can operate smoothly at that setting. Gotta go with a smaller coil at that low of a pulse delay. A small folded mono with a hot battery and 8usec delay... You will be closer to GMT-sized nuggets with that combo.

[Steve Herschbach]

37 minutes ago, Rod K said:

So how does the SL compare, depth wise, to 2 other lower cost PI units, the Garrett Infinium and the Tesoro Sand Shark?

The Tesoro Sand Shark is incapable of ground balancing and so is only suitable normally for beach detecting. It can be used in low mineral ground but then again, so can a good VLF. Bottom line, the Sand Shark is really a beach detector, not a prospecting machine.

The Garrett Infinium came out before the TDI. I think the TDI has the edge coil to coil by a slim margin but the main difference is the vast number of coils available for the TDI versus the Infinium, which if leveraged properly also give an advantage. The Infinium being discontinued now means unless you find one of the few left sitting on dealer shelves can only be had used.

True story also. Every one of the four Garrett Infiniums we had at Moore Creek eventually failed and had to go back for service, plus the one that one of my partners had. Five out of five! When you handle one you would think they are bullet proof but we proved differently. Unless you need waterproof, I would always chose a TDI over the Infinium.

[Steve Herschbach]

16 minutes ago, tboykin said:

Rob, thank you for the suggestions. The SL can safely handle up to 16 volts, and I've tested it with higher voltage batteries with a good increase in performance.

The issue with an 8usec delay is choosing a coil that can operate smoothly at that setting. Gotta go with a smaller coil at that low of a pulse delay. A small folded mono with a hot battery and 8usec delay... You will be closer to GMT-sized nuggets with that combo.

I would buy one of those.

[Hard Prospector]

For the small shallow nuggets in nasty mineralized ground, learned a long time ago not to use any coil on the SL larger than 10" (actually, the smaller the better). Hence, at the 8usec and smaller TDI coils a perfect match. Dan Geyer for a brief time made a TDI 4x6 Mono "Shooter" coil that runs so well on the machine that I can run the gain/sensitivity maxed out and the ground balance turned off EVERY TIME I use it and thats no kidding. The Miner John 5x9 Folder Over, Jimmy Sierra 6x10 Duel Field, White's 7.5 DF and the White's 7.5 Mono Aussi have also been good nugget producers and pretty much in that order.

I am 100% convinced that making these easy mods. could really be a great thing for the SL as a nugget shooter and revenue producer for White's.

 

[Ringmoney]

Scrap the current battery pack al together, there is plenty of space underneath the circuit board to hold a 2*4 cell 18650 li-ion battery, all is needed is a wider battery door to accept such a battery.

[Geotech]

I have a soft spot for the TDI-SL since it was my baby. Originally I had plans for taking it further, and if you look closely at the PCB you will see those plans. But the reality is, that platform has pretty much reached its limit, which is why I was spending all my efforts developing a whole new platform. Unfortunately, White's made some choices that killed the whole thing.

Reducing the delay to 8us is easy-peasy. Getting it to work is not. Getting it to work in a way that's manufacturable is even worse. If you measure carefully, you will even notice that the 10us setting on the TDI is actually closer to 11us. If a lower delay was easily doable on the SL, it woulda been done.

The reality is that the SL is fast approaching its EOL. There are new competitors on the horizon that will absolutely run rings around the TDI. If not the QED (and I'm as big a skeptic as anyone) then there are others. In the end, the only way to keep it alive will be to lower the price to $599, with free shipping. All this said, I whole-heartily encourage you to spend a lot of time & effort trying to improve the SL.

[tboykin]

14 minutes ago, Geotech said:

All this said, I whole-heartily encourage you to spend a lot of time & effort trying to improve the SL.

The great thing about these changes is they cost very little and improve the performance enough for one last hurrah before the next generation of machines comes out.... if they were to come out. Maybe we will just re-release all of the classics!

16 minutes ago, Geotech said:

But the reality is, that platform has pretty much reached its limit, which is why I was spending all my efforts developing a whole new platform. Unfortunately, White's made some choices that killed the whole thing.

I have heard a lot about you in my short time here. You are a smart dude, and I would love to shake hands with ya some day. Next time you're in the valley let me know.

As far as that platform I have no idea what you're talking about... Maybe it got boxed up and forgotten. Going forward our detectors will be bulkier, heavier, shallower, and have a shorter battery life than any other machine.

Here is a picture of the next generation of machines from White's, it runs on forty 9v batteries and hits a nickel at 2 inches---

[tboykin]

5 hours ago, Ringmoney said:

Scrap the current battery pack al together, there is plenty of space underneath the circuit board to hold a 2*4 cell 18650 li-ion battery, all is needed is a wider battery door to accept such a battery.

Tested with 4 18650's.... Interesting results at 16+ volts fully charged. Eight cells is unnecessary (and too heavy).

[Ringmoney]

1 hour ago, tboykin said:

Tested with 4 18650's.... Interesting results at 16+ volts fully charged. Eight cells is unnecessary (and too heavy).

The best quality 18650's at 3400 mah will last about 5 hours which is not great, if 2400 mah batteries are used, as in the Pro, 3 hours max can be expected. One of the main drawbacks of the SL is the battery life and here you are again talking of an inadequate capacity battery. Give people what they want a battery that lasts a bit longer.

[HardPack]

I just asked an uninformed question over on the "Impact of the New Nokta Three Frequency" post. 

As opposed to a multi-frequency metal detector, has there ever then a varible frequency MD with the varible adjustment on the control box?