specs
The settings for the Superscan are as follows -
TX pulse width 500uS
TX pulse frequency 86 pulses per second.
Sample pulse delay 60 - 150uS, adjusted by reject control.
Delay for second sample pulse 1100uS
Sample pulse widths 45uS.
The coil inductance should be 500uH for TX and RX, with a TX resistance of 1.5 ohms, including the cable.
Because of the low pulse rate and wide spacing between 1st and 2nd sample pulses, the unit can be affected by low frequency rf signals and power line noise. The MK2 version has a TX frequency control that can often counteract this. Also the integrator TC is adjustable (response speed) - slower smooths out the noise more.
For best signal on any object, the TX pulse width should be about the same as the decay time of the object signal. A large copper pan could have a decay time considerably longer than 500uS and not give as good a range as a similar size object of less conductive metal.
Ground signals from iron mineralised ground will be strong with a single TX/RX coil, but the Superscan was also designed to use separate TX and RX coils. An outer TX with and inner RX of half the diameter will give much less ground response. Also you can lay a big 10m x 10m TX coil on the ground, and search within it with a 0.5 or 1m RX.
Eric.
The settings for the Superscan are as follows -
TX pulse width 500uS
TX pulse frequency 86 pulses per second.
Sample pulse delay 60 - 150uS, adjusted by reject control.
Delay for second sample pulse 1100uS
Sample pulse widths 45uS.
The coil inductance should be 500uH for TX and RX, with a TX resistance of 1.5 ohms, including the cable.
Because of the low pulse rate and wide spacing between 1st and 2nd sample pulses, the unit can be affected by low frequency rf signals and power line noise. The MK2 version has a TX frequency control that can often counteract this. Also the integrator TC is adjustable (response speed) - slower smooths out the noise more.
For best signal on any object, the TX pulse width should be about the same as the decay time of the object signal. A large copper pan could have a decay time considerably longer than 500uS and not give as good a range as a similar size object of less conductive metal.
Ground signals from iron mineralised ground will be strong with a single TX/RX coil, but the Superscan was also designed to use separate TX and RX coils. An outer TX with and inner RX of half the diameter will give much less ground response. Also you can lay a big 10m x 10m TX coil on the ground, and search within it with a 0.5 or 1m RX.
Eric.
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