Fisher Gold Bug DP

The Gold Bug DP metal detector uses a single 9-volt ALKALINE battery. Do not use ordinary zinc carbon batteries or Heavy Duty batteries.

Hot rocks are rocks containing iron minerals that the detector will sound off for. They come in two basic types: Negative hot rocks are usually magnetite or contain magnetite and give a negative response because their ground balance value is a higher number than the soil they are found in. They are often dark in color, usually black, and usually heavy. They are usually attracted to a magnet. Positive hot rocks are iron-bearing rocks which have been oxidized by natural weathering processes so that their GRND BAL value is a number lower than the soil they are found in. They are usually, but not always, drawn to a magnet. They are most often reddish in color but are often black, brown, or yellow. Use a magnet to discriminate gold from hot rocks and iron.

EMI, or electromagnetic interference, can cause a metal detector to chatter spontaneously, to lose sensitivity for no apparent reason, or to cause periodic wobbly audio sound. Common sources of EMI include power lines, electronic communication equipment such as cellphones, fluorescent lamps, military electronics such as radar, other metal detectors and computer equipment. The primary reason metal detectors provide a sensitivity control (Gain and/or Threshold) is so that users can reduce sensitivity in order to eliminate response to electrical interference. Some users are reluctant to reduce sensitivity out of fear of losing depth. At reduced sensitivity settings, you may lose some depth, but at least you can still search.

Using the GROUND GRAB (GG) function to calibrate the detector will help you to maximize the detector's target identification accuracy and depth of detection.