huntindog1
Member
Found this info from another website thought I would pass it on.
TYPES OF QUESTIONABLE TARGET RESPONSES
When you receive a questionable signal of the Coin+Nail type, you are likely to hear either of these two almost repeatable audio responses:
1) initially a "broken" and "one-way" signal of a high-pitched tone AND nulling of Threshold if the iron nails or iron objects of a similar size are REJECTED in the Discrimination pattern;
As soon as you isolate the high-tone signal by approaching the spot with a search coil from different directions and using very short spans of coil passes, the signal becomes "two-way" repeatable.
2) a "broken" and "one-way" signal of a high or high-pitched tone AND a low-tone iron response to a nail if nails are ACCEPTED;
Like in the first case, as soon as you isolate the high-tone signal by approaching the spot with a search coil from different directions, the signal becomes "two-way" repeatable.
NOTE: In many cases, rusty wrought nails with large heads and square nails (cast iron) can cause the two-way repeatable audio responses of the Coin+Nail type due to their characteristic ability to exhibit both ferrous and conductive properties. They can be identified using accurate pinpointing: if the actual center (highest tone pitch and maximum volume) of the pinpoint audio response to the target is not where the center of the isolated high-tone signal was located during detection, the target is a rusty nail.
It is best to dig up these questionable signals to be sure before you master this technique. Just keep in mind that there are many variables "in the equation", and a number of possible "coin+nail" positions in the ground is infinite.
How To Recognize Ambiguous Responses To Coins Close to Nails with Minelab E-TRAC
With Minelab's FBS technologies, a signal is analyzed from a wide range of responses - 28 in total. This allows the E-Trac metal detector to analyze 28 times more target information than a single-frequency detector is allowed to process, and, therefore, the target identification is not only considerably more accurate but also remains that way under adverse metal detecting conditions.
Superiority of the Minelab FBS detectors to other brands' metal detectors also manifests itself in situations related to QUESTIONABLE responses to coins lying in close proximity to iron nails. Metal detectors of other brands do not have such effective means for dealing with ambiguous signals. The E-Trac's Smartfind system along with the FBS technology make it fast and simple for an operator to distinguish responses to good targets from iron false signals.
Upon hearing a questionable response of the Coin+Nail type (described on previous page), you should employ the following E-Trac features for signal analysis:
1) QuickMask's Smartfind window which shows the Target Crosshair position and the target's FE-CO properties on the screen - a 2-Dimensional Phase-Shift Scale;
2) "SIZING" option of the Pinpoint mode (activated by pressing the Pinpoint button on a Control Panel);
3) Depth Gauge with its range of 0-30cm (0-12 inches) from top to bottom.
To analyze an ambiguous target signal, you should follow these steps:
1) Switch to the QuickMask screen (an example of the QuickMask Discrimination pattern is shown here) by pressing the QuickMask button to open the Detect Screen Quick Menu);
2) Sweep a search coil, with extremely narrow and slow coil movements, over the signal spot. Make sure you get the most stable FE-CO reading by approaching the spot with a search coil from different directions or simply TURN 90
TYPES OF QUESTIONABLE TARGET RESPONSES
When you receive a questionable signal of the Coin+Nail type, you are likely to hear either of these two almost repeatable audio responses:
1) initially a "broken" and "one-way" signal of a high-pitched tone AND nulling of Threshold if the iron nails or iron objects of a similar size are REJECTED in the Discrimination pattern;
As soon as you isolate the high-tone signal by approaching the spot with a search coil from different directions and using very short spans of coil passes, the signal becomes "two-way" repeatable.
2) a "broken" and "one-way" signal of a high or high-pitched tone AND a low-tone iron response to a nail if nails are ACCEPTED;
Like in the first case, as soon as you isolate the high-tone signal by approaching the spot with a search coil from different directions, the signal becomes "two-way" repeatable.
NOTE: In many cases, rusty wrought nails with large heads and square nails (cast iron) can cause the two-way repeatable audio responses of the Coin+Nail type due to their characteristic ability to exhibit both ferrous and conductive properties. They can be identified using accurate pinpointing: if the actual center (highest tone pitch and maximum volume) of the pinpoint audio response to the target is not where the center of the isolated high-tone signal was located during detection, the target is a rusty nail.
It is best to dig up these questionable signals to be sure before you master this technique. Just keep in mind that there are many variables "in the equation", and a number of possible "coin+nail" positions in the ground is infinite.
How To Recognize Ambiguous Responses To Coins Close to Nails with Minelab E-TRAC
With Minelab's FBS technologies, a signal is analyzed from a wide range of responses - 28 in total. This allows the E-Trac metal detector to analyze 28 times more target information than a single-frequency detector is allowed to process, and, therefore, the target identification is not only considerably more accurate but also remains that way under adverse metal detecting conditions.
Superiority of the Minelab FBS detectors to other brands' metal detectors also manifests itself in situations related to QUESTIONABLE responses to coins lying in close proximity to iron nails. Metal detectors of other brands do not have such effective means for dealing with ambiguous signals. The E-Trac's Smartfind system along with the FBS technology make it fast and simple for an operator to distinguish responses to good targets from iron false signals.
Upon hearing a questionable response of the Coin+Nail type (described on previous page), you should employ the following E-Trac features for signal analysis:
1) QuickMask's Smartfind window which shows the Target Crosshair position and the target's FE-CO properties on the screen - a 2-Dimensional Phase-Shift Scale;
2) "SIZING" option of the Pinpoint mode (activated by pressing the Pinpoint button on a Control Panel);
3) Depth Gauge with its range of 0-30cm (0-12 inches) from top to bottom.
To analyze an ambiguous target signal, you should follow these steps:
1) Switch to the QuickMask screen (an example of the QuickMask Discrimination pattern is shown here) by pressing the QuickMask button to open the Detect Screen Quick Menu);
2) Sweep a search coil, with extremely narrow and slow coil movements, over the signal spot. Make sure you get the most stable FE-CO reading by approaching the spot with a search coil from different directions or simply TURN 90