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I am a novice just trying to get/make the right tools for the job. Any suggestions would be appreciated.
I am making two 2x3 foot (61cm x 91.5 cm) coils that will overlap about 1 foot (30.5 cm) to make a 3x3 foot (91.5 x91.5 cm) Double D coil for my Whites TDI-SL.
My research on this forum has shown that separate TX and RX coils will reduced (null, balance, quiet) the ground matrix better than a mono-coil. I am looking for buckle size and bigger items. I am looking for hut sites, trash pits, privies and general large disturbances in the soil.
Coil/pix 1 (yellow) coil:
20 AWG (.81 mm) is 19 strands of 32 AWG silver plated copper wire.
10 loops gives me:
5.0 ohm
313 uH
Coil/pix 2 (red) coil:
26 AWG (.40 mm) is 7 strands of 34 AWG silver plated copper wire.
12 or 13 loops gives me:
5.0 ohm
396 uH
Neither coil is spiraled, shielded or coaxed yet. I thought coil #2 would have less resistance and I would use it as the receive coil but now I will test them for lowest delay. Whichever coil can be used with the lowest delay will be my receive coil.
Any suggestions before I spiral wrap these loops?
Should or can I build a better/faster receive coil with smaller/better wire?
Can a damping resistor be used to reduce the resistance with a TDI?
For additional info - I plan on using an old electric lawnmower deck (plastic) for a platform. I am interfacing the TDI to a data logger and computer all mounted on the lawnmower deck. This will allow me to save the data from the site survey and manipulate the data with data logger provided software for 2D and 3D imaging. Kind of a poor mans GPR.
Fred
I am making two 2x3 foot (61cm x 91.5 cm) coils that will overlap about 1 foot (30.5 cm) to make a 3x3 foot (91.5 x91.5 cm) Double D coil for my Whites TDI-SL.
My research on this forum has shown that separate TX and RX coils will reduced (null, balance, quiet) the ground matrix better than a mono-coil. I am looking for buckle size and bigger items. I am looking for hut sites, trash pits, privies and general large disturbances in the soil.
Coil/pix 1 (yellow) coil:
20 AWG (.81 mm) is 19 strands of 32 AWG silver plated copper wire.
10 loops gives me:
5.0 ohm
313 uH
Coil/pix 2 (red) coil:
26 AWG (.40 mm) is 7 strands of 34 AWG silver plated copper wire.
12 or 13 loops gives me:
5.0 ohm
396 uH
Neither coil is spiraled, shielded or coaxed yet. I thought coil #2 would have less resistance and I would use it as the receive coil but now I will test them for lowest delay. Whichever coil can be used with the lowest delay will be my receive coil.
Any suggestions before I spiral wrap these loops?
Should or can I build a better/faster receive coil with smaller/better wire?
Can a damping resistor be used to reduce the resistance with a TDI?
For additional info - I plan on using an old electric lawnmower deck (plastic) for a platform. I am interfacing the TDI to a data logger and computer all mounted on the lawnmower deck. This will allow me to save the data from the site survey and manipulate the data with data logger provided software for 2D and 3D imaging. Kind of a poor mans GPR.
Fred
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