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Bounty Hunter 8400

Automatic VLF/TR

Page created April 26, 2009

NOTE: The following manual was scanned with OCR software. Be aware that there may be a few misspellings or anomalies due to the inaccuracies of the software translation. Images are excluded due to the memory requirements; therefore, there will be references to illustrations that do not exist in this text only document.

Bounty Hunter, Inc.


For buying our Bounty Hunter VLF/TR Automatic 8400. We are sure you will be pleased with the detector which features depth readout for coins in the all metal mode. Metered bad indication in the discriminate mode. Unit also has metered battery check capability. The 8400 does operate at VLF frequency to enable you to tune out adverse ground conditions in the all metal mode. The 8400 uses TR discrimination which enables you to tune out unwanted targets when operating in one of three preset discrimination levels.

As with any detector, the familiarity of the user with the instrument will have a great deal to do with how successful the treasure hunter is. We recommend that you read and understand this manual fully before attempting to use the instrument in the field.

Thank you again and I wish you many great finds.


Assembly of the 8400 is easy and requires no special tools. The only assembly required is to attach the search coil to the end of the lower stem.

A package containing~ the compression ring and coil hardware is supplied with the unit.

After the search coil is attached remove the knurled nut from the upper pole and slide onto lower pole. Then slide compression ring on pole. Insert lower pole into upper pole and slide knurled nut up with compression ring and tighten. See Fig. 2.

Next. wrap search coil cable around pole assembly and plug into control box. Do not use pliers on search coil wing nut or compression ring.


The following is a description of all the controls and switches on your 8400 and their functions.

MODE SELECTOR - Select ALL, METAL/DEPTH operation and three levels of discrimination

AUDIO ADJUST - Sets level of audio sound

GROUND ADJUST - Enables operator to tune out ~round mineralization

METER  -uses are for intensity of signal. Depth readout in all metal mode. Good Bad indicator in discriminate mode. Indicates condition of batteries in battery check A & B.

POWER SWITCH - Used to turn unit on/off and also check batteries

HEADPHONE JACK - for 1/4 inch stereo headphones

PUSHBUTTON TUNING - Pushbutton control is located at the end of plastic handle grip. This control enables instant retuning just by depressing button and releasing.


The basic instructions for tuning~ and operating~ your 8400 are attached to the meter of the 8400. These instructions are basic and are intended for a reminder when you don't have your instruction manual handy.

1. GOOD Indicator

In DISCRIMINATE mode if you get movement to right the object is good. NOTE if in foil mode it might be a pull tab.

Your 8400 uses two 9 volt transistor batteries (Eveready No. 91~ or equivalent). To test your batteries. switch power switch to A to test the A battery and to B to test the B battery. The needle must fall within the yellow box on the meter.


In ALL METAL/DEPTH mode of operation. Indicates depth of coin.

3. BATTERY Indicator

When the needle falls within the good section the battery selected is good A or B.


95% of all detector malfunctions are either due to faulty batteries or poor connections at the battery clip. Always check your battery condition if you feel your detector is not working properly. After you have connected and unconnected your batteries several times the prongs on the clip lead may spread apart or the prongs on the battery itself may be spread. Gently squeeze these prongs together with your fingers to insure a good snug fit.

Anytime you are going to store your detector make sure you remove the batteries. Storing the batteries in your refrigerator is the best place for them.


Hold your 8400 so that the search coil is about two feet above the ground and is not near any metal objects.

1. Set Mode Selector to ALL METAL/DEPTH position.

2. Set ground adjust to "0". This is a preliminary adjustment.

3. Depress and hold push button in. Turn power switch to on position. Release push button.

4. With mode switch in the ALL METAL/DEPTH position you will detect all metals and also be able to measure depth of coins up to six inches deep.

5. Adjust audio control until sound is just heard. When the 8400 is adjusted in this manner the 8400 is at its most sensitive setting~. Some "Thers" prefer no sound and in this case you want to make sure when you adjust for no sound that you have adjusted the audio level to where sound just disappears. This also is the most sensitive setting when you don't want to hear sound until you detect something.

6. To discriminate set mode switch to desired level of discrimination. Depress push button with search coil at distance from ~round that you want to search at. Depressing~ the push button will retune the unit for the ground conditions you are searching in.


This is accomplished only when the mode switch is in the ALL METAL/DEPTH position and is most accurate when the 8400 is correctly ground adjusted. Depth reading is only accurate on coins. Rusty small objects will show shallower than they really are. The 8400 depth reading is calibrated only to eight~ht inch search coil.


The ground adjust control only has an effect when you are in the ALL METAL/DEPTH position.

When unit is properly ground adjusted you will get no change in sound or meter reading as you lower search coil to the ground or raise search coil from the ground

To properly adjust ground first make sure unit is tuned with mode switch in ALL METAL/DEPTH mode. Adjust for slight sound so that you will be able to tell if sound goes away as you lower search coil to ground. After you have tuned your 3400 with search coil in the air. Lower search coil to ground and raise back up. If, while lowering your search coil to the ground you got an increase in sound, turn ground adjust control counterclockwise (left) if. you get a decrease in sound or sound went away altogether turn ground adjust control clockwise. When making these adjustments only turn control 2 or 3 increments at o time (about 1/4 inch).

After you make an adjustment depress push button handle to retune 8400 Repeat the procedure of lowering search coil and adjusting ground adjust control until you get no change in sound as you lower the search coil to the ground As you get less and less change in sound move the ground adjust less and less to avoid overshooting your no change in sound point.


In this mode you will be able to tune out items that you don't want to find depending on the level of discrimination you choose.

In addition to tuning out unwanted targets you will get a good or bad indication on the meter.

EXAMPLE: Try this with search coil in the air so that you don't have to be concerned with ground interference. Place mode switch to FOIL position. depress push button momentarily. pass a piece of tin foil by coil. sound will disappear and you will get meter movement towards bad. Pass a quarter by the search coil and you will get an increase in sound and meter movement towards good.

When you switch to PULL TAB you will tune out large aluminum screw caps. pull tabs, and tin foil.

CAUTION: In the DISC mode you need to keep the search coil distance between ground and search coil as constant as possible to avoid erratic readings and sounds. due to varying ground conditions.

If when searching in the discriminate mode the slightest change in distance between the coil and ground causes the 8400 to either sound off or the sound to go away. This condition is due to heavy mineralization of soil. To search when this happens depress push button when coil is 3 to 4 inches off the ground and then lower coil closer to ground ( 1-2 inches). You will loose some depth by doing this, but your 8400 won't be sounding off and going silent as you're sweeping the search coil.


When you have the Discriminator level set to TIN FOIL pull tabs will show good since you haven't tuned them out. When you have the discriminate level set to PULL TABS the large aluminum screw caps will show good. Also when you are set to the PULL TAB level most gold rings and all nickels will show bad.


The detector should be held as shown on page 10 in a position that is comfortable for you. Sweep the detector from side to side in about a three foot arc. The Bounty Hunter 8400 does not need to be hurried, so 9O at a pace that doesn't wear you out. Keep the detector tuned so that it is Just be~beginning~ to buzz. In All Metal Mode the detector ignores the ground, if properly adjusted. (See - Tuning Your 8400) In Discriminate, the ground will affect the detector, so you should sweep the detector at a constant height above the ground (about 1 inch). Irregularities in the ground as well as in your sweep height will cause variations in the tuning. A little practice with a coin buried at about 1 inch will enable you to pick out the target sound readily, as compared to the background variations.

To pinpoint or locate a target which doesn't peg the meter and , simply move the coil around to find the point where the loudest audio and highest~ meter reading;~ is S~given. The target will be right below the center of the coil. If the target response is so strong it pegs the meter and audio, simply push the tuning button momentarily over the strongest signal. This will tune out most of the response to the target and the detector will be totally quiet if it is moved away from the target. It may be necessary to retune a couple of times to almost totally tune out the target.

In the discriminate Mode, the tuning will be affected by changing the DISC Level control setting to identify the target by increasing the DISC level control as the coil Is passed repeatedly over the target. You will need to depress push button when changing levels until the target response goes away.

Remember, that in Discriminate Mode, it is best not to use any higher discriminate Level setting than necessary. Nickels and most small rings are rejected when the DISC Level is set to reject pull tabs on all TR Discriminators.

When switching from All Metal Mode to Discriminate Mode or vice versa you will affect the tuning. If the sound does go away, gets too loud when switching Modes, simply depress the Tuning Button momentarily.

For relic hunting or for coin shooting in areas that are free of trash, the All Metal Mode of operation will normally give best results, since the detector is easy to use with maximum sensitivity.


The 8 inch coplanar coil furnished with the Bounty Hunter 8400 is optimized for coin hunting but will work as well as most 8 inch coils for relic hunting.

The coil is waterproof and may be submerged in either fresh a salt water. Caution should be exercised to prevent water from entering the chassis. After the coil is used in salt water, the coil should be rinsed well with fresh water to prevent corrosion of the metal parts.

There are several good books to help the beginner learn how to use a detector, where to search and how to recover a target without damaging the environment. A good coin shooter can recover a lot of finds and leave the area looking as though he had never been there. Above all, always fill your holes when you have recovered the target.

The use of earphones will benefit you in two ways. Most earphones will very effectively block out most of the ambient noise, such as traffic noise and wind noise, which will enable you to better hear the fainter signals caused by the deeper targets. Secondly, using earphones will greatly extend the battery life, since it takes much less power to operate them. Any good 8 or 16 ohm set with 1/4 inch stereo jack will do.

HAPPY HUNTING, and thank you for purchasing a Bounty Hunter product.

This webpage brought to you by White River Preparium


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