The Name That Means Treasure!




Eldorado Field Test
By Michael O. Smith

About 6 weeks ago I received a call from James Gifford and Heidi of Tesoro Electronics asking me if I would field test their NEW Eldorado detector. Of course there was only one answer to questions of this complexity. Can you have it here by this weekend?

In the past I have field tested several machines and promoted their excellence, as duly earned by each unit. This time the format will be a little different, a more objective type field test. I guess I am best known for my use of the Bandido line. I did start out, however, with the OLD Eldorado and considered the Bandido as a progressive upgrade. Well, we have all heard what goes around, comes around. The Eldorado had gone around and here it comes again, that is the 2nd generation. Yes, it is now reborn as a new generation and truly unrivaled. Tesoro has put a lot of thought into this machine and covered all the bases one could hope for in one unit. On top of this, the price is unchanged from the Bandido II µMax and the lifetime warranty is still intact.

I will now present the field test and conclude with a little more subjective closing as is more my style.

FEATURES

In about 3 days I received the Eldorado. Inside the box was the new 9 x 8 concentric searchcoil with a 3 foot cable. There were 3 poles to be assembled. The main body of the detector was attached to the pole with the arm rest. A fresh battery was also included so that immediate use of the machine was possible. Included was the lifetime warranty card which should be filled out within 10 days of purchase. It took no time to lock the poles together with the spring buttons. I next adjusted the length of the pole to just in front of my feet so that I could swing the coil without lifting up my shoulders. I then opened the battery compartment and placed the 9 volt battery in. No wires, I liked that. Now it was time to go outside and try it out.

On the face there were several buttons and switches. I will briefly go over these and explain what each does. 1) Ground Balance, 2) Threshold, 3) Sensitivity, 4) Discrimination Level, 5) Battery Test - All Metal - Discriminate Modes, 6) Frequency Shift.

1) Ground Balance is a state of operation using specialized circuitry to ignore the masking effect that iron ground minerals have over metal targets. On the Eldorado, the Ground Balance control knob is a 3 and ¾ turn potentiometer.

2) Threshold is a continuous tone that establishes a reference point for tuning the detector to ground balance it. The threshold tone also establishes the minimum sound level for deep targets in the discriminate mode.

3) Sensitivity is the capacity of a metal detector to perceive changes in conductivity within the detection pattern. Generally, the more sensitivity a detector can smoothly provide - the more depth it will achieve in sensing targets.

4) Discrimination level is an adjustable circuitry which ignores or nulls audio responses from a specific conductivity range. This allows positive responses to be heard from metals higher in conductivity above the discriminate control setting. It is designed primarily to eliminate audio response from trash metals.

5) Mode Toggle Switch includes Battery Test, All Metal, and Discriminate Modes. All metal is any operating mode or control setting which allows total acceptance of any type of metal targets. It is usually associated with the Ground Balance mode.

6) Frequency Shift is a feature which suppresses the audio interference (crosstalk) between two detectors using identical transmit frequencies in close proximity.

FIELD TEST

Now that we have an idea of what all of the functions mean, I will step outside and go into action. Knowing that the unit needs to be set up in the general location of its use, I waited until I was on my site to set up. My first area was a river bluff with a lot of sand. Though I had worked this site fairly well, I knew there were some deep targets making this a good test site. First, I found an area with no iron signals in the all metal mode, then I performed the ground balancing act. The Eldorado performed this operation more easily than any other machine I have used. I set the threshold at a low hum. Then all I had to do was raise and lower the coil from about 10" to 1" and adjust the threshold balance-clockwise if the sound went down and counterclockwise if the sound went up. I did not have to re-tune or do any other action. This took about 1 to 2 minutes. Now that I was ground balanced, I pushed the toggle switch to the discriminate mode and started searching. I had set my discriminate knob at iron reject. In a couple of minutes I had my first positive signal. As with the Bandido, any positive sound, even from just one direction, that repeats itself when your swing speed and direction is repeated is probably a good target. My target did just that and was about 10" down. When I got it to the surface, it was a piece of iron about 1 x 2" in size. I raised my discrimination to the Nickel mark and found this eliminated the majority of small and medium-sized iron objects. Larger iron tended to sound good at times. I found that in such a situation, I could put it into the all metal mode and the detector would give a wide response, or I could simply turn up the discrimination knob a little and if iron, it would phase out. This could be done with one finger. I believe that with a little practice this will be an easy and quick operation. One advantage connected to this feature is the ability to easily locate an activity site in the woods by picking up small iron and then raising your discriminate level once you are in the center of the area. This can also help you relocate an area. A lot of the newer machines will not allow you to do this.

The depth that the Eldorado was getting was really exceptional. The next target was a nice soft positive signal from both directions which repeated itself. At about 10" I got a 1" pewter button , no marking, nice though. Over the next 2 hours, I unearthed buttons from 1cm to 4cm in size from 6" to 12" deep. Now that is fantastic for a worked out area. I did find one coin, an 1819 large cent about 8" down. I guess that was my reward for persistence.

The second test site was at our club's beach hunt at Tybee Island. Here I was in competition with about 30 other machines in a 40-yard area. Guess what, no interference from anyone. However, I did cause interference to one other hunter so I changed frequency mid-stream by simply pushing the toggle switch from 10.6 to 10.2 kHz, and I was no longer a threat. Need I say more about this unique feature? I did find a lot of coins and one token which won me a year's subscription to the North South Trader and my picture in their magazine. Another bonus.

The third test site was in the middle of the woods. This was a late colonial homesite, again searched for many years already. A little different challenge here with a lot of undergrowth, thick pine straw and more humus soil. Again, I was not disappointed. At first I had trouble finding the spot, but then I got smart and lowered my discrimination below iron. For a while I got no sounds, then a signal here and a signal there. Turning my knob above iron, they disappeared. Soon I was getting into the good area and the good finds. Note: The discriminate level may vary from machine to machine. With some of the other detectors you could not use this feature to find a site. As with many of the very sensitive units, I may get a signal when hitting a root or sapling, but this is easy to figure out since the sound would not repeat itself. Here I found a handful of buttons, some at the 12" level. My grand prize was a white gold ring with a ruby and two turquoise stones. The engraving was done by hand. This ring dated between 1790 and 1830. No disappointment here.

The fourth and last test site was at Panama City Beach, FL. On the beach sand, which was like dry white sugar and similar to hunting a flattened plowed field, I was truly hoping for a nice gold chain or diamond ring, but the law of averages was against me and I only found pocket change recently lost. I did get quite a few of those corroded tokens they call pennies. A lot of these were 8 to 10 inches deep and had been wet for a long time. Oh yes, 2 hotel keys which I turned into security. Now it was time to go to wet sand and surf. Over the wet sand I had just a few false signals but very few. I did dig a penny from 10" down, so I was able to confirm a positive difference between false and true signals. Standing on a high spot I put my coil underwater when the waves came in. Here I did get a false signal so I turned my sensitivity down to about 6 - 7 and all the false signals disappeared. Unfortunately, before I was satisfied with my settings, a big wave came in and covered my shoes and my pants. Oh well, so much for control over one's environment.

SUMMARY

In conclusion, the new Eldorado is a high-tech, multi-functional metal detector at a low cost and low operational complexity. It considers the fullest range of uses and adaptations of any metal detector and weighs only 2.2 pounds. The battery life is 10 to 20+ hours depending on the use of headphones. It uses only one 9 volt battery. Its unique features include a frequency shifter to give you the edge at competition hunts and around electrical interference. The Eldorado's simplicity of ground balancing is reflective of its entire character.

In this field test we have put the Eldorado through a number of different environments and found it to be most adaptable. I was surprised at how well it worked on the beach and in the salt water, much more stable than earlier machines. I would recommend the new Eldorado to anyone who likes variety and wants a high power, multi-function machine which is easy to operate and has a similar cost and weight factor: LOW!!

Happy Hunting!

Eldorado Field Test Using a 4” Coil
by D. E. Anderson, Anderson Detector Sales

When Tesoro asked me to do a field test report on their Eldorado metal detector, I was extremely pleased. I've been a Tesoro dealer since the early 90's and have always been able to sell a new Tesoro to people who want a lightweight machine, that's turn-on-and-go, and that has the controls needed to get the job done.

You don't need to hip mount the Eldorado because it's light anyway, but this Eldorado is even lighter. This field test is for the Eldorado with the 4-inch coil. The small coils have always been great for gold prospecting and coin hunting in those really trashy areas that you can't use a large coil. There are usually too many signals under one coil, and it can be confusing especially to a newcomer to the hobby.

FEATURES

Manual Ground Balance Knob control is a 3¾-turn control, which is plenty for a good coin machine. If the detector is not fighting ground minerals, it will go deeper to get the old coins or for whatever you are looking.

Threshold Knob is for adjustments for the background hum and is used when you ground balance the detector.

Sensitivity Knob adjusts the gain or power that the machine detects. It should be set for the most depth naturally but can be adjusted to keep the machine stable.

The Discriminate Level Knob is clearly marked. Its settings are Min, Iron, a Preset Arrow, Nickel, Pulltab, Zinc Penny, and Max, which is in red. It does a good job getting rid of your trash.
The Mode Toggle Switch is for All Metal, Disc, and the Battery Test.

The Frequency Toggle Switch is for changing the frequency when operating close to other treasure hunters and works to eliminate some electrical interference. It has three settings: Freq 1, Freq 2, and Freq 3.

FIELD TEST

The first test was at an old park that had been around for about 60 years or so. I had not paid a visit to this park in about 8 years. The reason was because of all the trash that was found before and the multiple signals. So this was a perfect area to test the Eldorado with the small coil. I started searching around the old oak trees (some of them were very large). My first signal came soon after I had started and had a clear loud tone. It turned out to be a wheat penny at 4½ inches. Not bad for a start with a 4-inch coil. I dug some junk around those trees but managed to get more clad and wheat pennies plus a 1940 silver quarter at 5 inches.

The park had been detected for many years, but the small coil seemed to make the difference in getting in-between all that junk. I didn't get multiple signals like I did when I was here before with the larger coils. All together in the old park, the Tesoro Eldorado found 7 wheaties, 6 clad pennies, 3 pulltabs, and the old quarter.

The second test was at an old home place, which I know had been detected, but I had never been their before. The old house was caving in and it was getting ready to be torn down. I managed to get there in time for a short hunt. The cows had cleaned up the tall grass nicely, so I didn't have to break out the Weedeater, which I faithfully keep in my van at all times. You never know when you arrive at an old place if it will need weeding before you can search it. I searched the backyard looking for the old clothesline poles. I had the Sensitivity set at 9 and the Discriminate Level at the Preset Arrow. I ground balanced the detector before I started searching (adjusting the ground control does make a difference). I started getting signals right off the bat close to the broken down back porch. A weak signal came up that was too steady to forget. I dug down 6 inches and was surprised to find a .58-caliber bullet. I knew there was Civil War activity near here, but I didn't expect to find any relics.


Nickels, clad pennies, a Wheat penny and a Civil War bullet between 3-6 inches.

I received another signal near a large tree in the backyard, and I had to find out what it was. I dug down 3 inches and pulled up a Buffalo nickel. I could not make out the date, but it was in good shape. After searching the old home for a while, I decided to call it a day to get back to the shop.
The old house produced more nickels than anything. I dug 8 nickels, 7 clad pennies, a wheat penny, and the Civil War bullet at varying depths from 3 to 6 inches. Most of the nickels were deeper and were dated back in the fifties except for the Buffalo. I did get some aluminum junk, but it wasn't much. I thought that was pretty good for a 4-inch coil.

The third test took me to an old creek area where gold had been found before. It's not far to drive, but it does require some hiking. The weeds were tall and snakes were bad in this area, so I stuck close to the creek bed most of the time. An old house foundation was just up the hill from the creek. It was a hot day, so I tried to keep myself in the shade as much as possible, but that's where most of the signals came from anyway. The first loud clear tone from the Eldorado came about 50 yards from the old house foundation. I dug down 5 inches and pulled out a small buckle made of brass. It had tuned green but was in good shape. It was only 1½ inches long and ¾ inches wide.

There were many signals, so I knew a larger coil would have been confusing. Most of the signals were iron because I turned down the Discriminate Level control to check. I received another clear signal closer to the house foundation. I dug it up and it turned out to be a thimble, which was also brass at 4 inches deep. Another tone came from the 4-inch coil and it was an old button. I had no idea who the man was on the button, but it looked like the words around the picture were Russian. After several more digs, it was getting rather late, so I decided to get back.


Using a 4” coil with the Tesoro Eldorado can help you find your way through those junky or heavily weeded areas. Found on one of the hunts: an oddly shaped piece of lead, a brass piece, a button, a zinc penny, a gold plated ladies ring, a thimble, and a buckle.

Overall finds at that creek area near the old foundation were interesting, and I received a lot of enjoyment finding things from the past even if I did not know what some of them were. An oddly shaped piece of lead, a brass piece, the button, a zinc penny, a gold plated ladies ring, the thimble, and the buckle turned out to be good hunting for a small 4-inch coil. I found very little junk while searching this spot, and I think that's another plus for the smaller coils.

The fourth test was interesting because it took me to Appomattox, VA. Our shop is only about 18 minutes away. The Eldorado was ground balanced before this hunt. The ground mineralization in sections of Appomattox has always been the most difficult for metal detecting. Once again Tesoros have performed well in this area.

I had received permission to hunt where an old house once stood. The house burned down around 1920. You could still make out the foundation of the house because pieces of it were still sticking out of the ground. Not far from this area, the Confederate troops had retreated toward the courthouse to surrender. The field had been cut, but the weeds were still a few inches high. That makes the small 4-inch coil come in handy again because it went in-between the clumps of grass whereas the larger coils would lose those valuable inches in depth. My first strong signal came about 50 yards from the foundation. Digging down 6½ inches was a large brass gear. The landowner came by later and told me that it was off a small field Carronade (short iron cannon). He said it could be an elevation adjustment gear. He had previously researched this area and was very educated on the Civil War activity that had taken place.


Some interesting historical finds—a small buckle or latch, 3 Civil War bullets, 2 small lead balls, a lantern piece, an unmarked button, a large brass gear, a harmonica reed piece, and another brass object.

Another strong signal from the Eldorado turned out to be a part to a lantern at several inches deep. Of course it was badly damaged—they usually are. I have found these before while relic hunting in the Appomattox area.

I received several good signals in the field most at 4 to 7 inches deep. The small coil did great searching between the thick clumps of weeds and getting close to the ground.

The Civil War retreat produced some interesting historical finds—a small buckle or latch, 3 Civil War bullets (one with a solid base), 2 small lead balls, the lantern piece, an unmarked button, the large brass gear, a harmonica reed piece, and another brass object.

SUMMARY

The Tesoro Eldorado did a great job, and I was very pleased with the results using it with the small 4-inch coil. I have to say that in all the junky or weeded areas that treasure hunters sometimes search, it's worth it to have a great metal detector like a Tesoro and to always have a small coil as part of your treasure hunting equipment.

D.E. Anderson is an authorized Tesoro dealer who operates Anderson Detector Sales in Lynchburg, VA. If you have any questions about this article or about any other Tesoro product, he can be reached at detectorman@earthlink.net


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Tesoro Electronics, Inc. 715 White Spar Road Prescott, AZ 86303 USA 1-928-771-2646