GPX-4500 GPX-5000 Modified compared to GPX-6000

I should of used a 12" Mono coil to get the same detection as the GPX-6000 but it was late in the day. That compression in the dynamic range that the GPX-6000 could be a deficiency in the ADC via using Delta Sigma adc, it maybe something else all together, as i say, i did not design it and who knows what goes on in the FPGA. It still does the job very well and it would be interesting to do testing on some hotter ground.