Jim in Idaho

Great work, Jason!

Jim

2 hours ago, Jeff McClendon said:

Hi Jim,

I did not say that the TDI Pulse Scan modded by Reg was running at 14.4V. I used the nominal voltage written on the Whites battery to make sure that readers  of this post knew that the TDI I was using was a big box TDI and not an SL. I charged up the battery using the stock Whites charger. Where that charger cuts off is the amount of voltage that the battery being used was charged to.

I have had an SL fry on me using jacked up batteries. I am not doing that anymore.

Th

The 0.1 gram gold nugget target was detectable by the TDI with the Sadie coil using those settings in air testing.

This was an in the ground test using containers of very mineralized dirt with plenty of magnetite particles and volcanic material.

I did not try to make the TDI I was testing look bad. However, its single channel ground balance system could not handle those dirt samples as well as the other two detectors. 

I understand, Jeff.  I'm curious what the actual voltage was. Also, I wasn't criticizing the test. And I agree air tests don't mean much. But my SL has often targeted a 1 grain gold bar at 3", in the ground. But, I have no experience with Arizona, or Colorado soil.

Jim

My only question is why run the TDI at 14.4v? The nominal is 14.8, and the max is 16.8. I'd bet my SL would give a response to that .1 gram nugget, since it gives a response to a 1 grain piece. Granted, it's not a 6000, or Axiom, but it didn't cost me thousands, either.

Jim

The newer models, made sometime in 2015 and later, included a modification suggested by Reg Sniff.That mod has been done, by several people, to the earlier machines. It increases the sensitivity. Other than that, they're all the same.

Jim

I remember hiking in and staying overnight on Piru Ck. We lived in Simi Valley at the time. I remember my dad talking about the gold there. Hard for me to believe, but that was 65 years ago!

Jim

Yup....looks like melted beer bottle glass.

Jim

Ilmenite, maybe? Titanium iron oxide. Not sure if ilmenite is magnetic.

Jim

Yessir...,that is REALLY cold doins, for sure. Worst I saw was a job at Crested Butte Colorado in '73. -44 every single morning for 10 weeks. But super arid, and with the high elevation (10,800') sun, not that bad. Wind is a super-killer. Back in Feb of '89 we had -40 and 40mph wind for several days. Windchill at -90. Killed everything that couldn't find shelter from the wind....elk deer, antelope (lost 80% of the state herd), coyotes, cattle, sheep. Same happened in '48- '49, but I wasn't here then...LOL. Easy to look back on, from a warm house, but not funny at the time. John, up there in Edmonton, puts up with extreme temps a big part of the time. Don't know how he does it...Ha!, but he's got my respect.

Jim

1 hour ago, Ridge Runner said:

John  

 I’ve seen it so cold that I had to put one sleeping bag in another trying to keep warm. Even then I wasn’t sure  that I wasn’t going to freeze to death.

 Chuck 

Yup, Chuck. I remember, back in my fur-hunting days, mid December, sleeping in the divide basin in Wyoming at 7,000', in the open bed of my little Chevy LUV 4x4. One bag inside another, and my Air Force arctic parka over the whole thing. Not a human within 40 miles. Worst part was getting up in the pre-dawn at -20 degrees, and praying the truck would start. ..................................best days of my entire outdoor career....LOL

Jim

John, I'd take a good look around, at the area, for future reference. Get a good idea in your head about why that patch is where it is. Might lead you to more of them. Great job in any case.👍

Jim

LOL....what are friends for, if they can't help?

Jim

1 hour ago, PI-Man said:

Jim — I am still kicking — 1.5 yrs cancer free so far. Just move a little slower now a days and I still need to find a gold coin.  Doing good had a bunch of other medical procedures done this year since I was in for my 500,000 mile tune up.  Lol.  You didn’t tell me this getting older stuff can be painful at times 😂 

Yup....gettin' old is not for sissies, for sure. I'm approaching 75, and this has been one of those seasons where I feel like I did a big leap downward. Still hiking uphill at 8,000', but I'm feeling it more, and the legs just don't have the power they did a few years ago. I'm really happy with your progress. Not everybody heals as well as you have. Keep it up!

Jim

5 hours ago, PI-Man said:

See what happens when I take a little break from the forum.  I missed a great thread.  Cali I PM’d you sorry for delay.  

Yep I am the guy who probably bought out all the Panasonic and Rubicon caps years ago after they were being discontinued.  I bought hundreds since it was a minimum order from the vendor.   Didn’t need hundreds just worked out that way.  But I can tell you I do go through a bunch when finding the right pair for the job.  

Karl — thanks for explaining to everyone about why we match caps (important) and the many other things you explain to all of us.  

Wow some good work being done out there!  
 

Yup, Gary, it's like "Back to the Future"....LOL. Hope you're doin' good buddy!

Jim

I really appreciate the great pics, Pat! Nice work. I'm also eagerly looking forward to field reports...even birdshot finds and depths...LOL.

Jim

IMHO, a person should move with caution on any mod not suggested by either Reg Sniff, or Karl. I doubt a 10% increase in gain would be noticeable in the field. Some mods are all about the risk/reward ratio. Same goes for boosting the voltage...at some point you're risking the health of your machine for very little increase in depth/sensitivity. Boots on the ground, and geologic self-training on where to detect would make a bigger difference.

Jim

I had no negative effects from doing the SS mod. Looks like you did a good job on the switch. Wish I had time to do that mod on mine. With the dry sluice project, and the resistivity, I'm buried in projects...LOL. Having a LOT of fun with the resistivity, though it's fairly boring setting up and collecting all the data. Best of luck on the gold, Pat. Looking forward to tests and results.

Jim

9 hours ago, Geotech said:

Here is a diagram for clarity. I've labeled components both for the SL and the [TDI/TDIpro]. Note that only the SL has test points.

I have never tried this mod so I don't know what the results will be. The purpose of C42/R75/U7d is to eliminate DC offsets and reduce bounce-back noise but maybe it's overkill. If all you want to do is short C42 then I recommend lifting pin 10 of U7 [or removing Q16] or cutting the trace.

 

Karl, I'm curious about what controls U7d? Thanks.

Jim

6 hours ago, CaliGold said:

Thanks Karl! and @Jim in Idaho The metal detector Gods have spoken...

 

pat

Thanks, Pat, but don't confuse my tiny bit of knowledge with Karl's far great ability. Compared to him, I'm a hack with a small bit of experience with one particular detector. We're very fortunate to have him to explain all this to us, and I, for one, am grateful.

Jim

I appreciate that info, Karl! I had thought it required some serious surgery to change the timing. Definitely more than I want to tackle.

Jim

11 hours ago, CaliGold said:

Thanks Jim

Completely lost as to what that means tangibly. I know you guys are trying to educate me, but I think I need direct orders. soooo, Solder a 1k resistor in-line somewhere along one of the two wires going to the toggle switch between the two test points? I'm basically gonna solder one wire to Test Point 2 and another wire to Test Point 31 and  neatly route and connect those two wires to the two different tabs on the bottom of this switch in photo below. I'm clueless as to where to put a resistor in this scheme. I ordered these 0805 resistors and sounds like they are the wrong kind. I'll have more time tomorrow to take crack at it. I just put that resistor on top of the cap in photo to show scale. Why God Why.

 

Thanks

Pat

resistor can go on either side of the switch, Pat. Solder one resistor lead to switch, and the other to one of the wires. The resistor is in series with the switch. So TP2, resistor, switch, TP31. OR, TP31, resistor, switch, TP2.   Doesn't matter.

Jim

As far as I understand, the delay on the SL can't be lowered below 10 microseconds. The timing circuit is fixed.

Jim

No, Pat...the resistor has to be switched into and out of the circuit. So, when the switch is "on" the resistor covers the cap. When the switch is "off" the circuit goes back to the factory setup. In effect your changing the circuit from not allowing DC current through the cap, to allowing it past the cap via the 1k resistor.

Jim

You want the resistor to be across the cap when the switch is "on". Don't fool with the cap. As Karl said...without the resistor in series with the switch the output of the opamp would be directly shorted to ground.....not good...LOL. I'm looking forward to some comparison tests with the switch on and off.

Jim

I have no idea on the switch. I'll definitely install one when I do this mod. As far as the test point location, I was more interested in where TP2 was in the schematic, but appreciate the pic in any case.

Jim

Many thanks for the explanation and schematic Karl. I think the mod called for a jumper from test point 31 to test point 2? I'm not sure where TP 2 would be.

Jim