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Hello Friends,
I had been visiting this forum in recent past to reach to the excellent inputs from MD gurus. Having worked on PI detectors I decided to start with VLF detectors.
I made a 12” TX coil and an 8 shaped differential RX coil size 8, processing I used in following way: RX coil -> Instrumentation
Amp -> Sampling -> Integrator -> Low Pass Filter -> DC Offset removal -> DC Amp. I have sampled both the RX channels independently from which I get 2 different signals from each half of the coil.
When I put metal on D1 (i.e. first part of the of the RX coil) it goes +ve and D2(i.e. other half of the coil) goes –ve this is as expected but the problem that I am facing is that when I remove metal from the D1 the signal at D2 rises which is detected by the A/D circuit and I get detection alarm at this stage also
.
Therefore in this config I get 2 peaks in detection one when I bring metal close to D1 and other when I remove metal from D1. I know principally there is nothing wrong in this behavior, but I need to know how I can overcome this problem so that detector works successfully. I would really be obliged to the valuable suggestions provided.
Another thing I wanted to know I that what are the advantages of this coil configuration or is there any better coil configuration possible as my priority is max depth and ability to pinpoint the target.
Thanks
I had been visiting this forum in recent past to reach to the excellent inputs from MD gurus. Having worked on PI detectors I decided to start with VLF detectors.
I made a 12” TX coil and an 8 shaped differential RX coil size 8, processing I used in following way: RX coil -> Instrumentation
Amp -> Sampling -> Integrator -> Low Pass Filter -> DC Offset removal -> DC Amp. I have sampled both the RX channels independently from which I get 2 different signals from each half of the coil.
When I put metal on D1 (i.e. first part of the of the RX coil) it goes +ve and D2(i.e. other half of the coil) goes –ve this is as expected but the problem that I am facing is that when I remove metal from the D1 the signal at D2 rises which is detected by the A/D circuit and I get detection alarm at this stage also
.Therefore in this config I get 2 peaks in detection one when I bring metal close to D1 and other when I remove metal from D1. I know principally there is nothing wrong in this behavior, but I need to know how I can overcome this problem so that detector works successfully. I would really be obliged to the valuable suggestions provided.
Another thing I wanted to know I that what are the advantages of this coil configuration or is there any better coil configuration possible as my priority is max depth and ability to pinpoint the target.
Thanks
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