Category Archives: underwater detection



Your new TESORO metal detector was designed to provide you with many happy hours of enjoyment in the most rewarding hobby I can think of – treasure hunting. Ahead of you lie fascinating and exciting experiences as you step into the past, uncovering artifacts lost by past generations. I wish we could share these experiences with you, and we wish you the best of success.

Your Tesoro metal detector is capable of meeting your needs in a wide range of treasure hunting situations. As with any detector, operator and familiarity is probably the limiting factor in determining how successful you will be. We recommend that you read and understand this manual fully before attempting to use the instrument in the field. Then, as you practice and become familiar with your detector, your rate of success will increase dramatically.

Your TESORO metal detector is a precision electronic instrument, which will last for years if properly cared for. Treat it right and it won’t let you down.





The Tiger Shark uses microprocessor technology to create a true dual function machine. In Normal Mode, the Tiger Shark works like any other Tesoro detector. It uses the same great ground balance and discrimination features that made the Bandido and Eldorado series so successful. On land, the Tiger Shark can be used for coin and relic hunting and even gold prospecting. By using the four controls on the outside, you can fine tune your detector to handle whatever conditions you are working in.

We all know that working in the wet salt areas is different than working in any type of dry area. This is where the Tiger Shark outshines the land detectors. In land conditions, the most crucial adjustment is using the ground balance to tune out mineralization. In wet salt conditions, changes in the conductivity in the sand cause most of the problems. The Tiger Shark uses a completely different set of internal settings in the SALT Mode than in the NORM Mode. There are no special controls or techniques to remember. When working on a salt water beach, just switch to SALT Mode, adjust the Ground Balance and start hunting.

The Tiger Shark continues in the tradition of other great Tesoro underwater machines by having interchangeable coils available. Along with the 8″ coil that comes standard with the detector, we also manufacture a 7″ and a 10 1/2″ coil. To see if one of these coils is right for you, ask your local dealer or check the section in this manual titled “Selecting the Right Searchcoil.”



Your Tiger Shark was shipped with these parts:

1 Upper Pole Assembly

Fully assembled, including upper pole stem with handle grip, padded arm bracket, and pole lock.

1 Control Housing With Headphones Attached

1 Middle Pole Assembly With Pole Lock

1 Lower Pole Assembly

Fully assembled with 2 washers and nylon nut and bolt.

1 8” round printed spiral searchcoil with 8′ cable

1 8-cell battery pack with 8 AA batteries installed

1 Tube of Dow Corning #4 silicone

2 Velcro cable straps

1 Operator Instruction Manual

1 Tesoro Warranty Card

If any of these items are missing, contact the Tesoro Authorized Dealer where you purchased your detector immediately.


    1. On the lower pole assembly, remove the mounting screw and thumb nut from the black nylon pole tip.
    2. Insert the pole tip between the mounting ears of the searchcoil and align the holes of the pole tip and washers with those of the mounting ears.
      Note: The pole tip should fit very snugly into the mounting ears.
    3. Insert the mounting screw through the holes in the mounting ears and pole tip entering from the side opposite the cable connection.
    4. Install the thumb nut on the mounting screw and tighten by hand.
      Note: Do not overtighten the thumb nut. It should be snug, but not too difficult to loosen up.
    5. On the middle pole assembly, depress the two spring buttons and slide the middle pole assembly into the upper pole assembly until the spring buttons click into the holes, thus locking the two assemblies into place. Tighten the pole lock to secure the two assemblies together.



  1. Slide lower pole into middle pole until spring buttons click into the first set of adjustment holes. Turn pole lock to tighten, thus locking the assembly into place.
  2. The Tiger Shark can be assembled in several different configurations. Take a look at the pictures below to find out the best configuration for you:Control housing mounted under arm
    Control housing mounted under pole
    Divers setup (lower pole set directly into upper pole)

    Body Mount

    Converting the Tiger Shark from pole mount to body/belt mount is simply a matter of removing the control box from the upper pole and unwinding the cable. To remove the control box from the pole, depress the four spring buttons that hold the mounting bracket and control box to the pole and lift. It is easiest to release one set of spring buttons at a time.

  3. Once you have decided on a pole mount configuration, wrap the cable around the pole leaving enough slack near the searchcoil to permit searchcoil adjustment.
    Install the coil connector into its receptacle on the back of the control housing and tighten it fingertight.

Note: Do not use pliers to tighten the coil connector. Do not allow the cable to flop loosely over the searchcoil. Since the detector is sensitive enough to “see” the tiny wires in the cable, a floppy cable can cause false signals as the searchcoil senses the moving wires.



The Tiger Shark has been equipped with a drop-in battery pack. To install or replace the batteries, make sure the detector housing is dry, then release the two draw bolts securing the faceplate to the housing. Gently pull the control panel free being careful not to twist or strain the ribbon cable connecting the faceplate panel to the printed circuit board. The Tiger Shark takes 8 AA size alkaline batteries. Also, make certain that you follow the polarity indicators on both the battery holder as well as the batteries themselves. Then check the polarity of the pack as it goes into the housing. Look inside the housing for the two spring clips and slide the pack so that the battery pack terminals meet the spring clips. There is only one correct way to put the battery pack in. If the batteries are put in wrong, the detector will not work. Replace the faceplate and use the drawbolts to clamp the faceplate back onto the housing.

Do not rest the unit on the coil connector while clamping the faceplate. This can cause excess wear and damage to the connector.

IMPORTANT NOTE: Always make sure the instrument is dry before opening. Water, if allowed to make contact with the circuit board, may damage it. Always make sure the O-ring is clean and free of dirt or sand. It is recommended that you wipe the O-ring with a dry cloth and look for damage and apply a new coat of diver’s silicone grease before replacing it. Failure to maintain the O-ring will result in extensive damage and will not be covered under warranty.


The searchcoil angle and stem length should be adjusted so that the unit does not become uncomfortable or tiring to hold after long periods of use. The detector should rest in your hand with arm relaxed allowing it to swing back and forth without having to lift with the elbow or shoulder while keeping the searchcoil as close as possible to the ground without touching. The pole length is adjusted by depressing the spring buttons and extending or shortening the lower stem until they click into the set of holes that give you the most comfortable setting. The searchcoil should rest about one inch above the ground while standing erect. Adjust the angle of the searchcoil so that it is parallel to the ground. Tighten the searchcoil thumbnut by hand so that the searchcoil will maintain this setting.


The Quickstart is designed to teach you how to use your new Tiger Shark. It provides a quick and easy means of learning your detector and the concepts behind all of the functions.

Important Note:

The Tiger Shark has two very different modes of operation. Normal is used for dry land hunting or fresh water hunting. Salt Mode is for wet salt sand and salt water hunting only. The modes cannot be interchanged. When you switch modes, you are actually changing the internal setup of your Tiger Shark. Please be very aware what mode your detector is in while you are hunting.

The controls for the two separate modes on your Tiger Shark operate almost exactly the same. As you follow the Quickstart, it will be assumed that you are operating in the Normal Mode. Any differences between the Normal and Salt Modes will be noted. You may want to go through the Quickstart in Normal Mode first and then repeat it using the Salt Mode.

You will need the following items:

  1. Your fully assembled Tiger Shark Detector.
  2. An iron target (a small nail or screw will do), a nickel, a pull tab and a quarter.
  3. A fine jeweler’s screwdriver.
  4. A nonmetal table or counter surface.

Here’s what you will do:

  1. Perform an Audio Battery Test.
  2. Set Ground Adjust.
  3. Perform Air Test in ALL MET Mode.
  4. Check and Set the Internal Controls.
  5. Perform Air Test in MOTION DISC Mode.
Prepare for the Quickstart

Place your assembled Tiger Shark on the nonmetal surface as shown in the photo below. Make sure there are no metal objects near the coil and remove any jewelry from your hands and wrists.

Start with the controls like this:

  1. Mode in the OFF position
  2. TUNE SPEED in the ALL MET FAST position
  4. GROUND ADJUST at 12:00
Perform Audio Battery Test

Turn the Mode Switch from OFF to NORM (if you are doing this test for the Salt Mode, switch from OFF past NORM and directly into SALT). This will turn on the detector and will give you a number of beeps. If the batteries are fully charged, you will hear 6 or 7 beeps. As the batteries drain, you will hear fewer and fewer beeps. When you hear one or two beeps, it will be time to replace your batteries.

After the beeps are done, you will hear a slight humming sound. This is the threshold tone. Its purpose is to give you a reference point to judge targets by. Some targets may be small enough or deep enough that they will not be able to generate an audio signal by themselves. By monitoring a threshold, you already have a signal so changes in that signal will be easier to hear. However, if the threshold is set too loud or too soft, small changes in the signal will be hard to hear. We will be talking about changing the threshold tone a little later.

Set Ground Adjust

We will now set the GROUND ADJUST for the air test. This method is only for the Quickstart tests. See the section “Ground Balancing Your Tiger Shark” for the correct procedure for ground balancing your Tiger Shark in the field. Please note that the NORM and the SALT Modes work at different ends of the GROUND ADJUST knob.

Ground balance for the NORM Mode: Turn your GROUND ADJUST knob clockwise or towards the positive side for 5 full turns. This will take you past the end range of the GROUND ADJUST potentiometer. The knob has no end stops, but you may notice a very slight increase in the drag of the knob as it passes the 3 and 3/4 mark. By turning the knob 5 full turns clockwise, we are assured that the GROUND ADJUST is in the very farthest positive position. Once you are at the positive position, turn the GROUND ADJUST knob a 1/2 turn counterclockwise or towards the negative side. This is an air test position only that will let you proceed with the rest of the Quickstart.

Ground balance for the SALT Mode: Turn your GROUND ADJUST knob counterclockwise or towards the negative side for 5 full turns. This will take you past the end range of the GROUND ADJUST potentiometer. The knob has no end stops, but you may notice a very slight increase in the drag of the knob as it passes the 3 and 3/4 mark. By turning the knob 5 full turns counterclockwise, we are assured that the GROUND ADJUST is in the very farthest negative position. Once you are at the negative position, turn the GROUND ADJUST knob 1 turn clockwise or towards the positive side. This is an air test position only that will let you proceed with the rest of the Quickstart.

Perform Air Test in ALL MET Mode

Once you have set the GROUND ADJUST for the Quickstart, you are ready to perform an air test in the ALL MET Mode. You will notice that there are two ALL MET positions – ALL MET FAST and ALL MET SLOW. These positions refer to the speed at which your threshold tone retunes itself. The ALL MET FAST should retune in about 1 to 2 seconds after a target response, whereas the ALL MET SLOW may take 4 to 6 seconds to retune.

Leave your detector in the ALL MET FAST position and wave any of your test targets 2 to 3 inches in front of the coil. Notice that you will have a positive response as the target passes the center of the coil and that the signal will fade away to silence after the target is past the coil. The threshold tone should come back in 1 to 2 seconds. Now move the TUNE SPEED switch into the ALL MET SLOW and try waving your targets again. You should notice a very distinct difference in the amount of time that it takes for the threshold to retune. ALL MET FAST will be used most often to quickly pinpoint targets. ALL MET SLOW is used to pinpoint deep or small targets that do not create much of an audio signal or for tracing the outlines of large targets.

Please return your TUNE SPEED switch to the ALL MET FAST before continuing with the Tiger Shark Quickstart.

Check and Set the Internal Controls

There are three controls that are located on the inside of the detector. The Volume control, the Sensitivity control and the Threshold control. All of these controls have been set at the factory for optimum performance in most conditions. However, if there is some need to fine tune these controls, you will need to open the waterproof case to perform the adjustments. We recommend that you do this on a clean dry surface (a clean beach towel that is spread out will do fine). When you are done with the adjustments, visually inspect both the control box and faceplate making sure that no sand or other contaminants have gotten onto the O-ring as it may cause leaks.

When you open the detector case, it will release the batteries from the contacts and cause the detector to stop functioning. While you are making adjustments, it will be necessary to place a slight pressure on the battery pack to make the detector work. When you reconnect the batteries to the contacts, the automatic battery test will be heard. Once the case is open, reach over the top of the detector with your left hand (or right if you are left-handed) and gently press the batteries onto the contacts. Use your fine jeweler’s screwdriver to adjust the potentiometers inside the case.

If you would like to set the internal controls, please continue with this section of the Quickstart. If you would prefer not to set the internal controls, please switch the TUNE SPEED to MOTION DISC and skip down to the section marked “Perform Air Test in MOTION DISC Mode.”

Setting the Volume control: The Volume control is the only potentiometer that is located on the printed circuit board. To adjust your Volume control, open the case and put a slight pressure on the battery pack. After you hear the battery test you will be able to adjust the volume that you hear in the headphones to a comfortable level. Use your screwdriver and turn the potentiometer clockwise for more volume and counterclockwise for less volume. Take some time and find the most comfortable level for you.

Setting the Threshold control: The Threshold control is located on the back of the faceplate/switch set and is the potentiometer closest to the edge of the faceplate. As explained in the “Perform Audio Battery Test” section, the threshold is a slight steady tone that is used as a reference point to judge targets by. Some targets may be small enough or deep enough that they will not be able to generate an audio signal by themselves. By monitoring a threshold, you already have a signal so changes in that signal will be easier to hear. However, if the threshold is set too loud or too soft, small changes in the signal will be hard to hear. To adjust your Threshold level, open the case and put a slight pressure on the battery pack. After the battery test, use your screwdriver to turn the potentiometer clockwise to increase the threshold tone and counterclockwise to decrease the threshold tone. Take some time to find the best threshold tone for you.

Setting the Sensitivity control: The Sensitivity control is on the back of the faceplate/switch set and is the closest to the center of the faceplate. To set the Sensitivity control, you must first switch to MOTION DISC. The Discriminate circuit uses a silent search mode meaning that no sound will be heard until the coil goes over a target. The most common use of the detector will be to hunt in the MOTION DISC Mode and then switch to an ALL MET Mode to pinpoint a target. This will give you the advantage of ignoring unwanted targets and not having to listen to the threshold hum until you are ready to recover a target.

The ALL MET circuit uses a single channel to detect various metals. The MOTION DISC circuit uses two different channels, then amplifies and filters the signals, and then compares the two to determine whether or not to beep at a target. While this is a great advantage for ignoring unwanted targets, it can make the circuitry more susceptible to interference. A number of outside conditions such as power lines, highly mineralized soil and wet salt sand can cause interference. The Sensitivity control is used to raise or lower the power to the operational amplifiers, which changes the gain. Gain is the measurement of how much a signal is amplified. The higher the gain, the more depth and sensitivity to small objects a detector has. Unfortunately, any small interference that is amplified can cause the detector to become erratic. The Sensitivity control is used to find the best gain setting in any location without letting the detector become unstable.

Turn the TUNE SPEED switch from ALL MET FAST to MOTION DISC. With the case open, place a slight pressure on the battery pack and wait for the battery test to finish. When the battery test is done, you will not hear any sounds in your headphones until you pass a target in front of the coil. Using your screwdriver turn the potentiometer clockwise to increase the gain and counterclockwise to decrease the gain. Take some time to try waving targets in front of the coil with different sensitivity settings. Notice that with a higher sensitivity setting, the farther away from the coil a target can be and still get a response. Please note that your detector will probably “chatter” at maximum sensitivity. This is normal and will not hurt your detector. The best setting is to set the Sensitivity control to a point just before the detector starts to chatter.

Perform Air Test in MOTION DISC Mode

As discussed before, the Discriminate Mode is used to filter unwanted targets from good targets. The principle behind this is pretty simple. The detector sends out a signal and then receives it back creating a small electronic field. As metal passes through the field that the detector generates, it causes a change in the received signal. The amount of change that each type of metal causes is fairly constant; therefore, we can tune our detectors to miss the targets that we don’t want to find. The change is based on the type of conductivity that each target has. The general list of targets is as follows: iron, foil, nickels, gold jewelry, pull tabs, screw caps, pennies and silver coins – starting with dimes and working up to silver dollars. This list is meant to be a guide only. There is a point that some gold rings and some pull tabs overlap. Also, the depth of the target and its orientation in the ground can change the received signal. A coin that is flat to the coil will produce a better signal than a coin that is on edge. Take some time now to try different combinations of depth and orientation of your targets and find out how your detector responds.

We are now ready to discriminate targets from each other. We will start with the DISC LEVEL at zero. Wave the targets one at a time at least 2 1/2 inches away from the coil. All four targets (the iron, nickel, pull tab and quarter) will respond with a good audio signal. Next, we will turn the DISC LEVEL up to approximately 3 or 4 (2 or 3 in the SALT Mode). This should be high enough to knock out the iron target and still get a positive response on the nickel, pull tab, and quarter. When you are done with the iron target, turn the DISC LEVEL to approximately 6 or 7 (4 or 5 in the SALT Mode). This level is high enough to knock out the nickel. At this time the iron target and the nickel should give no response, while the pull tab and quarter will give a solid response. Next, turn the DISC LEVEL to approximately 7 1/2 or 8 1/2 (7 or 8 in the SALT Mode). At this time only the quarter should respond with an audio signal. Now roll the DISC LEVEL all the way to MAX. Notice that the quarter is still responding. The discrimination will not go high enough to lose most silver coins.

This air test was designed to show you how the MOTION DISC Mode works. Each machine may be a little different than all the others, so you may want to take some time and try different targets to find the responses of your machine. At a later date, you may also build a test garden to test your detector in the field.


Congratulations, you have just finished the Quickstart for your new Tiger Shark metal detector and in the process have learned quite a lot about your detector. But experience is the best teacher. I would recommend that you get out and practice with your detector as much as possible. Any time spent using your detector will give you valuable experience.


Ground Balancing Your Tiger Shark

Now that we have gone through the Quickstart, you are now ready to take your Tiger Shark out and learn how to ground balance. (Note: If you have not gone through the Tiger Shark Quickstart, it is strongly recommended that you do so before ground balancing your Tiger Shark.)

Ground balancing is a simple but very important skill that you must master to get the most out of your detector. The Tiger Shark has controls that will allow you to tune the detector to the exact ground matrix that you are hunting in. Finding and maintaining the exact tune or balance will give you the highest possible depth and stability for your conditions. Once you have read through this section, it is most important that you get out and practice your ground balancing skills as often as possible.

To start, find an area that is free of metal targets. If your coil is over any targets, it will always give a positive signal and it will be impossible to correctly ground balance your detector. Start with your Tiger Shark in the ALL MET FAST position. (You can use the ALL MET SLOW position, but it will take a little longer to do your ground balance.) At this time, it will not matter where your GROUND ADJUST knob is set. Place your DISC LEVEL at MIN and switch the MODE switch to NORM. After the battery test is done, you are ready to begin the ground balance procedure. (Note: Unless you are on a wet salt beach, do not use the SALT Mode. It will not ground balance to normal conditions. The SALT Mode is to be used only on a wet salt beach.)

Lift your detector straight off of the ground about 6 to 8 inches. Keep the coil parallel to the ground. At that height, your detector will not be affected by the ground mineralization. As you lower the coil, the detector will read the ground matrix and let you know how to adjust to achieve aground balance. (Note: You must lift your coil straight up. Do not swing it like a pendulum.) Once you have got a steady threshold, quickly lower the coil straight down to approximately 1 inch off of the ground and listen to any change that may occur in the threshold. You will hear one of three sounds: 1) the threshold will get louder or go positive 2) the threshold will go quiet or become negative, or 3) the threshold will stay the same.

If the threshold stays the same, the detector is telling you that the ground matrix is not affecting it and you are ready to hunt.

If you get a positive or negative signal, the machine is telling you that it is being affected by the ground matrix and must be adjusted for peak performance.

If your threshold goes positive, you must turn the GROUND ADJUST knob counterclockwise or towards the negative side.

If your threshold goes negative, you must turn the GROUND ADJUST knob clockwise or towards the positive side.

Once you have made an adjustment, lift the coil up, let the threshold retune and push the coil down again while listening for any sound change as the coil drops. If there is a threshold change, follow the above directions and repeat until you have very little or no threshold changes on the way down. A very slight positive response is better than any kind of negative response.

If there are threshold changes on the upstroke do not pay attention to them. As you raise the coil, the detector goes from a ground matrix (soil) to no ground matrix (air) and that difference will most likely cause some change in the threshold tone. Only changes on the downstroke are to be adjusted for.

Now that your detector is ground balanced, you are ready to hunt. You can stay in either of the ALL MET Modes or switch into the MOTION DISC. Whichever mode you choose to hunt in, it is always necessary to ground balance in an ALL MET Mode first.

Just like any skill, ground balancing must be practiced constantly. The easiest place to do it is in your backyard or any place close that has at least a 10 foot by 10 foot area. First, check for any metal targets and remove them. When the area is clean, take your Tiger Shark and ground balance it. When you are done, spin the GROUND ADJUST knob either positive or negative and ground balance again. Keep up this practice until you feel comfortable with ground balancing. Take some time to keep your ground balancing skills sharp and you will see better results in the field.



Selecting the right searchcoil for the type of detecting you’re doing will add greatly to your success.

In addition to the standard 8 inch open center searchcoil, two optional coil sizes are available for the Tiger Shark. The 10 1/ 2 inch open center coil is designed for areas where digging is easier and where junk targets may not be too numerous. The 7 inch coil will be particularly useful when searching for smaller targets, such as gold nuggets.



The sweep speed of the detector is slow enough to allow pinpointing in the Motion Discriminate Mode but will require a little more practice. Move the coil slowly from side to side and then from front to back over the target. Raising the coil slightly and slowing the sweep speed will narrow down the detection area enough that it’s easy to tell where the coil center is at the instant of sound.

Another easy method is to sweep the coil from side to side across the target in very short sweeps as you slowly move forward and backward across the target. Slow down the sweep rate and shorten the sweeps until you just barely get a response at one spot. The target will be directly below the coil center at this response time.

The easiest way to pinpoint for most people will be to switch to the ALL METAL Mode, since no-motion is required. To pinpoint a target that doesn’t saturate the audio, just move the coil forward and back and side to side until you get the strongest sound. The target will be directly below the coil center. If the audio saturates over a large area, simply hold the coil over the target momentarily to detune the detector. This will narrow its field of response to allow you to once again seek the area of strongest response.



Congratulations, you have just purchased a new metal detector, and we wish to thank you for choosing Tesoro.

So many people are disappointed when their new “state-of-the-art” detector becomes less and less exciting to use and doesn’t seem to go as deep anymore. There is something that you can do to keep your new detector working as good as when it was new.

The most important thing is simply to remember that your detector is an electronic instrument and to treat it as such. You wouldn’t expect your TV set to operate properly if you stored it in the trunk of your car, would you?

We have generated the following list to help you take care of your detector and to help ensure that you do not void its warranty. If you will follow its guidelines, you will find your detector will not let you down.

  1. Operate your detector exactly as recommended in this Operator Instruction Manual.
  2. Do not attempt to modify or repair the detector’s electronics.
  3. Cable is hard-wired into searchcoil. Do not attempt removal of the spring retainer on the searchcoil housing.
  4. Use only high quality carbon-zinc, alkaline, or nicad batteries. Remove batteries during long term storage. Never substitute batteries of other voltages. Brands should not be mixed. Do not attempt to modify the power supply system.
  5. Never spray lubricants such as WD-40 or any types of cleaners, sealants or other chemical preparation on or into the detector.
  6. Avoid banging the searchcoil against rocks or foundation walls.
  7. Always protect the searchcoil with a properly designed scuff cover.
  8. Remove and clean out scuff covers periodically to avoid buildup of mineralized or metallic particles.
  9. After use, clean the detector with a soft cloth to remove any dust, moisture, or other contaminants.
  10. Do not transport or store your detector in the trunk of your car.
  11. Keep cables properly wound to stem and protected. Floppy or pinched cables may short causing erratic noises or unnecessary replacement of searchcoils.
  12. Protect the detector from dust, moisture, and extreme temperatures during storage. Avoid storing it in places such as attics, basements or garages. When shipping the detector, use the original factory carton or a similar heavy-duty container. A one inch minimum clearance of padding around the detector must be provided when shipping.
  13. Treat your detector as you would any sensitive electronic instrument. Although ruggedly constructed and designed to withstand the demands of normal treasure hunting applications, it is not intended to be improperly operated or abused.


Operating Frequency 12.5 kHz
Searchcoil Type Round, open center concentric
Searchcoil Size 8 inch Diameter
Audio Frequency Approx. 270 Hz
Audio Output Stereo Piezo Headphones
Weight (may vary slightly) Less than 4½ lbs.
Battery Requirement (8) AA DC (alkaline)
Battery Life (typical) 10 to 20 hours
Optimum Temperature Range 30° to 100° F
Operating Modes No-Motion All Metal – (Fast & Slow Tune)
Normal Mode
Salt Mode
Silent Search Motion Discriminate
Maximum Depth Rating 200 ft.

Your Tesoro metal detector is covered by a Lifetime Warranty, the terms of which are listed below. If your metal detector should require service, you may return it to the Tesoro factory at the address below.


This warranty gives you specific legal rights, and you may have other rights which vary from state to state.

This instrument is warranted to be free of defects in material and workmanship as long as it is owned by the original consumer purchaser. This warranty is not transferable and is valid only if the warranty registration card has been completed and mailed within 10 days of purchase.

TESORO will, at its option, repair or replace any instrument covered by this warranty, without charge, except for transportation charges, at its factory in Prescott, Arizona.

This warranty excludes batteries, damage caused by leaky batteries, cable breakage due to flexing on body mount units, and wear of the searchcoil housing. Also excluded are instruments which have been abused, altered, or repaired by an unauthorized party.

Under the copyright laws this documentation may not be copied, photocopied, reproduced, translated or reduced to any electronic or machine-readable form, in whole or in part, without the prior written consent of Tesoro Electronics Incorporated, except in the manner described in this documentation.
© 2001 Tesoro Electronics Incorporated. All rights reserved. Printed in the United States.

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Keep your search team up to date with this informative newsletter.                   There are sections on Commercial News, International News, and Law Enforcement & Dive Rescue News.                   Find out how underwater cameras are helping engineers make critical decisions about the repair and maintenance of submerged structures from hydroelectric dams to the hulls of ships. See how ROVs and sonar systems assist in environmental studies and what they are doing for the aquaculture industry.                     Stay informed on the new tools being used by law enforcement agencies to strengthen homeland defense and learn how underwater metal detectors help police put more criminals behind bars. Discover which government agencies are performing underwater search operations and why.   Learn about the business of underwater salvage and find out how to make money finding what other’s loose.

Another popular section of the newsletter is Treasures Recovered!                   It includes everything from the search and recovery of a lost diamond ring to complete articles on the salvage of ancient treasure ships. You’ll be amazed at the variety and quantity of “treasures” pulled from rivers, lakes, and oceans around the globe.



One of the problems in towing an instrument underwater, is the long length of cable required to get the device down to depth.  A typical ratio of cable length to tow depth is 4 to 1, which means 400 feet of cable is  required to tow at a depth of 100 feet.  Increase the tow speed and even more cable is needed to get to depth.  To overcome this problem a depressor wing is used.  With the wing, the ratio is cut in half which means the equipment can be towed at a depth of 100 feet using only 200 feet of cable.  The advantage is obvious; no more piles of cable on the boat deck and smaller, less expensive cable handling systems can be used.       In the past, many of these depressors were custom made to fit specific equipment.  This meant the wings were expensive and had limited applications.  JW Fishers saw the solution to these problems as a universal wing that could be used with any type of equipment, and developed the DDW-1 deep dive wing.  The DDW is assisting a variety of users from government agencies and universities, to police departments and marine service companies.  The list of government groups using the wing is extensive and includes the U.S. National Marine Fisheries Service, the Argentine Navy, and the Maritime Administration of Latvia.  Institutions of higher education employing this device are as geographically diverse as their applications for the wing.  They extend from the Univeristy of South Carolina to University of Alaska.  The collection of marine services companies using the DDW-1 cover a broad spectrum, from giants like Ireland’s Korec Group to privately owned civil engineering companies like Isreal’s Merterre.      Taking advantage of the wing’s diving ability is a broad range of equipment in a variety of applications.   The Fisheries Service is using their wing in conjunction with the TOV-1 towed underwater camera system to survey reefs and other marine ecosystems.  The Office of Emergency Services in Fairfield, California and the Buffalo Police Dept. in New York also operate a towed camera with the DDW-1.  They use it to search for deep water drowning victims.  The Argentine Navy and Varna Diving Company in Bulgaria both use their wings with a proton magnetometer to search for sunken vessels.   Sources Equipment LLC in the United Arab Emirates also use the DDW with a proton mag, but their primary mission is to locate and track oil pipelines.  A number of law enforcement agencies are using the depressor wing with the side scan sonars to search for drowning victims, submerged vehicles, and capsized boats.  These departments include the Allegan County Sheriff in Michigan and Suffolk County Police on Long Island.       One of the most interesting projects involving the deep dive wing is the search for a historic shipwreck being undertaken on the north east coast of England.   A consortium made up of members from the Filey Town Council and the Filey Underwater Research unit are using the wing with an underwater metal detector in a hunt for the remains of the Bonhomme Richard.  Commodore John Paul Jones of the American Continental Navy fought a battle from this vessel which has been described as “a brilliant action at sea of classic proportions”.

underwater search newsletter


Underwater Search Newsletter

JW Fishers has increased the size and scope of its popular newsletter Search Team News.   The publication includes numerous articles on underwater search operations performed by government agencies, commercial divers, law enforcement agencies, and military units from around the world. One section of the newsletter titled “Law Enforcement and Dive Rescue News” describes the use of metal detectors, underwater cameras, and side scan sonars by police, fire, and dive rescue units.                 Another section describes the type of operations performed by universities and government agencies using underwater search equipment.                 In the “Commercial News” section, the work of commercial diving and marine services companies is detailed.                 Their projects include tracking underwater pipes and cables, locating lost ship anchors, and inspecting underwater structures like dams and bridge supports.

One of the most widely read parts of the newsletter is “Treasures Recovered”.                   Here are the exciting stories about recovering silver bars from sunken Spanish galleons and finding priceless artifacts in the remains of ancient sailing vessels.                   The articles range from the projects of professional treasure hunters searching for pirate booty, to the hunts of weekend divers looking for lost rings and coins.                 Many of these “treasure hunts” take place on beaches and dive sites close to your own hometown, while others are in exotic places half way round the world.

There is also a section titled “International News” that chronicles the underwater work of overseas companies and foreign governments. There are short excerpts describing who is using which type of equipment for what kind of projects, like how a power company in Ireland is using of an underwater camera system or why a government agency in Thailand is using a side scan sonar system.

The back page of the newsletter has all the latest company news from JW Fishers,                 information on the newest products and technology for underwater search operations, and contact info to submit a story or to get more information on one of the articles.                 There is also a “Customer Feedback” column where e-mails and letters from customers are printed.

The most recent issue of the newsletter includes articles about; a power company saving millions with the help of an ROV, the discovery of a “virgin” treasure wreck in Canadian waters, and how a mystery involving one of this country’s deepest lakes was solved with an underwater camera.

New light system for underwater camera

New light system for underwater camera

JW Fishers has developed an external light system for their popular MC-1 mini camera.   The compact underwater camera is ideal for use where low cost or small size is critical. The new light system provides high intensity lighting to optimize picture quality. One or two lights can be attached directly to the camera housing with a specially designed, easy to remove bracket.                 The lights are available with either 100 or 250 watt quartz halogen bulbs and are water cooled to ensure long bulb life. Power is supplied from the surface allowing unlimited operating time.                 The standard mini camera system includes a 500 foot depth rated underwater housing with black & white camera and 150 feet of umbilical cable. The camera sends live video through the cable to the surface for viewing and recording. Any TV or video monitor can be connected to view the clear, sharp video images produced by the underwater camera.

The mini camera and lights are ideal for any type of underwater inspection operation.                   The 6 inch long, 2 inch diameter camera housing can easily be mounted to a diver’s helmet or lowered into a pipe for internal inspections. An internal ring light with high intensity LEDs provides the lighting when performing internal pipe inspections with the mini cam.   The MC-1 is currently in use by commercial diving companies worldwide giving topside tenders and supervisors with their own view of the worksite. The mini camera is also being used by law enforcement agencies and military units to search for evidence or explosives, and to survey underwater sites before deploying divers.                 Other applications for the system include inspection of seawalls and shiphulls by attaching the housing to a long pole handle and maneuvering it from the surface.                   Two east coast companies recently reported new and unique uses for this mini underwater camera. A Rhode Island company that manufactures sediment sampling devices attached an MC-1 to their equipment so the operator could view the area being sampled, and a dredging company in Florida attached the camera to their equipment allowing the operator to view the bottom before and after dredging operations.

A number of options are available for the MC-1 system including cable lengths up to 1,000 feet and color or PAL (European) format cameras.                 The color camera is a great option for those applications where a color picture is important such as viewing benthic habitats. The mini camera’s housing, lights, and brackets are all constructed of corrosion-proof PVC and urethane to give years of trouble free performance.

Fishers light up your underwater world

Fishers light up your underwater world

Known for their extensive line of underwater search equipment, JW Fishers has expanded the product line with the introduction of a new underwater light system. For over 10 years the company has produced underwater lights for use on their ROVs and other underwater cameras. As a result of customer demand, the lights are now being offered separately. Two different light systems are available, the DHL-1 dual underwater light and the SL-1 single underwater light. Both lights are ideal for any of the numerous underwater inspection projects encountered by today’s commercial and professional divers, including hull, dam, and bridge inspections.

The DHL-1 features two side by side lamps mounted in a holder with attached handle for ease of use by divers. The SL-1 is a single lamp which can be attached to a diver’s helmet or mounted on any underwater structure. Several single lamps can be ganged together in an array for lighting large areas. The light beam is provided by high intensity quartz halogen bulbs that are water cooled, ensuring long bulb life. Both lights are available with either 100 or 250 watt bulbs. The SL-1 and DHL-1 are surface powered by either 120 volts ac or 12 volts dc which allows them to supply continuous lighting for extended underwater operations. A 150 foot cable with abrasion resistant jacket is included with the light, and cable lengths up to 1,000 feet can be supplied. The lights have slightly negative buoyancy and weigh only a few ounces in the water.

Fishers underwater lights are economically priced with the base cost of the SL-1 system at $395 and the DHL-1 at $695. These underwater lights have a depth rating of 1,000 feet and are constructed of high impact, corrosion proof PVC and urethane to provide years of trouble-free performance. Both are covered by a two year warranty.

Just over a year ago JW Fishers introduced their new DDW-1 deep dive wing

Fisher’s Deep Dive Wing makes a Splash!

Just over a year ago JW Fishers introduced their new DDW-1 deep dive wing. The wing is designed to be attached to any towed underwater instrument and make it dive deeper using less cable. Ideally suited for use with side scan sonars, magnetometers, and underwater cameras it has gained wide acceptance in the underwater search and survey industry. Since it’s inception the DDW-1 has become enormously popular with a variety of different users.

A Florida marine services company, Resolve Marine, is using their deep dive wing with a magnetometer and towed underwater camera system to locate WWII submarine detection cables. Researchers at the University of Alaska have attached an underwater camera to their DDW-1 to perform foraging studies on several whale species. University spokesperson Briana Witteveen says, “One application for the system is to help determine prey types”. The Chevron oil company is using their wing with a Proton 4 mag to locate and track pipelines in Nigerian waters before drilling new wells. A dive shop owner in Holland, Michigan searches for shipwrecks and other objects lost in the great lakes with his side scan sonar and deep dive wing. A group of Florida treasure hunters bought a wing to use with several of their towed instrument packages including underwater metal detectors. Connecticut based Counterpoint Marine has their DDW-1 attached to a boat-towed metal detector to assist in searching for anchors, moorings, pipelines, and a variety of other targets. The Department of Fire Services in Hong Kong uses a side scan sonar and deep dive wing for search and rescue operations. “The wing helps us get the sonar down deep, beyond the range we can search with our divers”, says the department’s Terry Tsui.

The compact size and 45 pound weight of the DDW-1 make it easy to deploy from any size search vessel. The wing’s high weight to pull ratio creates a significant downward force which maximizes the depth of the towed instrument using a minimal amount of cable. Best of all is the deep dive wing’s PVC and stainless steel constuction that make it impervious to salt water and corrosion.