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Jim Straight, October 16, 2015 in Geology and Ore Deposits
Just out of curiosity Jim - why are you interested in one of these?
We can still talk about them. I've seen pictures but never seen one in operation and I am interested how they work.
Cant be many of these out there still in fully functional, operational condition. I'm sure a few, but not many.
First Texas may have one on hand as a museum specimen.
Chris... to cut to the quick... I acquired a vacuum tube two box that originally
belonged to the Utah State Collage and was sold as surplus. It was
manufactured in 1946 and used high-voltage batteries to drive 5-vacuum
tubes... It is a direct descendent of Dr. Gerhard Fischer (Fisher) original 1931
Metallascope and patented in 1937. With the development of Transistors in
the 1950s; it became known as the Fisher M-Scope Gemini-series.
My vacuum tube two-box used large-size, heavy and cumbersome high
voltage batteries. But depth it had, and I was able to detect magnetic black
sands at depth. Black sands are often associated with placer gold if in a
metalliferous area..... Also the two box could be useful to trace out
condictive metals.... Unfortunately the batteries we now expensive and
the vacuum tubes in high-power drain them fast. So I used it spairnly
and they were special order in a cardboard rectangular box with a short
shelf life. One box was the transmitter and the other the receiver..jim
Do you think the older vacuum tube type had an advantage over the newer transistor versions?
Or were the transistor versions of the two box about the same, just running on a lower voltage system?
Why don't you use a Discovery TF-900. It uses 6 AA batteries with an estimated life of 20 hrs.
It has "All Metal" mode with ground reject, and a TR Cave Mode that responds to no or low mineralization.
It had a depth capability of 15-20 ft on a 50 gal barrel and 20-30ft on a car, to the best of my relocation.
I also use an ArcGEO Logger to record the grid responses to use on a laptop to display the data.
I have never used it on these targets, but used the 73khz Pipe Finder circuit to locate water lines at 4-8 ft. It uses a separate transmitter and different coil to find pipes. If you get good you can even accurately estimate the depth, by using the 45 deg response technique.
A Better method to MAP Black Sand deposits is the Hand Held Magnetometer, an inexpensive model that should be adequate is the Flux Gate Magnetometer by Carl Mooreland at the GeoTech Site.
Another method would be to use Induced Electrical Current sensing system, ie Electrical Resistivity. It is accurate to Hundreds of Feet, and will give you a color map of the deposit if you use ResDev 2d or 3d software
These can all be researched on the GeoTech website.
Bill "Lost Adams"
Bill you are correct; but still do not count out the Gemini 3 for locating and mapping blacksand
concentrations; but back when I was using the Vacuum tube Metallascope it used large high
voltage batteries to power up the tubes and as you know there are still advantages the tubes
have over transistors and I punched down deep and if in a metallogenic area the blacksand
was most likely associated with placer due to its gravitational association.
Changing the subject if you are lost adams Bill you could be looking on the wrong area. But I have
no idea where it is; just where it ain't... jim
ICMJ Associate Editor Chris Ralph:
(Chris, I mailed you a photo of me using my 1946 vintage Fisher Metallascope
as my photo on this forum... I would be most appreciative as I can no send
photos. It is legal. George Shields took it and Chris Gholson gave me permission
to use it; ref pg 139 in his co-authored Rich Hill)
I did pretty good with this vintage/obsolete vacuum tube type that needed expensive
high-voltage primitive carbon type battery packs that were needed
to drive the 5-tubes two-box deep... yards (feet)... not inches into the sub-soil
formation while seeking a conductive hard rock vein, that I failed to find
I was most successful in locating large concentrations of magnetic black sands
that are often associated with placer (gold,electum,silver) deposits due to both
having a higher specific gravity... Depths 3 to 6+ feet; usually on a caliche, hardpan
or other bedrock. For a buried 50 gallon drum up to 10 ft or more; but who in their
right mind would spend the effort to dig a deeper hole unless it was tossed into a
For treasure hunters My original metallascope was NOT senitive to raw metal less in
size as a trashdump of buried cans that were into a shallow shaft up to say 9-ft deep.
But the Fisher Gemini 3 is great to locate a can or even a saddle-pouch of buried loot.
Quart size canning jars filled with coins been said to have been found at posthole
depths of three to five feet...
Here is Jim using his two box detector:
(I scanned it for him and post it here:)
Jim, the "Lost Adams" moniker is from my different Names and pursuits.
My name is William V. Adams
I hunt and Find Lost gold mines and treasures.
I spent a good bit of time researching the "Lost Adams Mine" on the Border between Arizona and New Mexico.
I do Admit I have NEVER been LOST in the Boonies.
At times I have been a mite bewildered as to where I was though. Only when I was much younger though, Not Recently!
If you look on my Facebook page or my LinkedIn page you can see the Pic of me Looking Lost.
couldn't figure out how to post a pick here???
As far as the Lost Adams Mine is concerned I believe that it is at or very near the Ancient Apache Chiefs burial grounds, where ever that is. I personally wouldn't go near the area, even IF I knew where it was, as I believe it is Guarded by a Warrior or two that aren't bound by anything except Ancient Tradition. Hence IT NEVER Being found in modern times. And If you do you never LIVE to tell the Story.
Thanks Chris... It sure looked like I needed to diet... camera angle :rolleyes:....
Bill, I reckon the lost adams is named because it is lost... But You are not
lost; thus I sense you have a couple of great stories to relate if you have
a mind to do so. And for sure I would be delighted to read one.
Chris my Vacuum tube two box needed a dry-cell in both the transmit and receive box.
Each drycell Rayovac BA-51 were 67.5 volts and lasted about 9 hrs. It used highvoltage
and punched down deep... as far as raw depth about as good as the Gemini-3 but mine
lacked the refinements of the later transistorized Gemini's.
But I have quite a story to relate... but I struggle to write a good article; but it could be
a good article... jim
Bill If seeking for lost gold mines and treasures is what you like
to do; go for it. You could find it while others miss. And it could
be in the cards you will be even if you miss the one you are
seeking; you could find a heretofore overlooked one.
Over the recent years I have noticed more interest in two-box detectors. Since the
receiver and transmitter searchcoils are separated, their depth capabilities are to
be measured in feet instead of inches. They work because they measure the changes
in conductivity under the receiver "box." Their depth depends on the mineralization
of the soil and the size and shaped of the conductive soils.
Back about 2010 on another forum I was bashed by claiming depthjs of three or more
ffeet to locate concentrations of placer gold.within the metaliferous dry south-westerm
deserts. The method is smple, just use a two-box to seek concentrations (pockets
and channels) of magnetic black sand; but to be fair, as I did not mention I was using
my vacuum-type two-box instead of a conventional detector and being ruthlessly
bashed I picked up my marbles and that was that.
However I was using this method.... crude I will admit, but by virtue of free-milling placer
and magnetic black sand being "bed-fellows," I was able to trace-out magnetic black sand
concentrations that carried eluvial placer deposits. Like a bolt out of the blue, I
became aware of the relationship of regional geology to the types of placer deposits.
More later, I got a lota backyard cleanup to do and I is slow as I use a walker; but it is
great to be out and about...Off subject... Hey, Chris if all goes well I will be in the Valley
Prosepectors booth at GPAA gold and treasure show n Pomona Febr. 20-21 and looking
forward to seeing you and your dad... jim
:DI picked up a Bounty Hunter TimeRanger and discovered that it does pickup black magnetic sands when looking for gold in all metal mode , I know most people think a Bounty Hunter just junk but this unit is not , I own a number other detectors from different companies and none of my other units will do this , I ground balanced it and started searching and it started going off with a faint signal and irregular pattern and I was thinking to my self what a heap , so I ground balanced again and again , that is when I started to dig up the small signals and found out the detector followed the outline and center of the black sand deposit in all metal mode , I tested this about 20 times now and it always finds the gold , because I have some very fine placer flood gold here and the eddy currents and beach topography determine where the gold finally lands and it is in the black sands 99% of the time , I am already on a large inside corner of a gold bearing river , sometimes I end up with just black sands and no gold but that is why you take your pan and screen along to sample and see what is in the area you want to work !!! If you find a good deposit bring out your high banker and start moving some yardage !!!
I have picked up large objects, a smashed Cadillac hub cap at 3 feet deep in all metal mode with my Bounty Hunter Pioneer 505 , right after my Whites TDI battries died , I brought the 505 as a backup and I have hit some extremely deep targets with my BH TimeRanger in all metal mode a small fence post at 2 feet , the two box detectors will go very deep but it has to be a large object like an airplane or a car or a 50 gallon drum my Garrett GTI 2500 with a two box hits some extreme depths !!! 10-25 feet !!!
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