You can use this circuit - just add 2 more delayed samples (GB1/GB2) to your regular circuit (MPP for example). op amp 5.2 is your regular intergrator (s1/s2); and op amp 5.1 is going to be connected to the delay samples integrator (GB).
GB1 = 10us after S1
GB2 = 10us after S2
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No this is just answer to the question of the topic (just a regular TDI/GoldScan ground balance with manual adjustment).
I'm curious about doing auto GB and I don't see this being discussed anywhere.Leave a comment:
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I have read and on how newer VLF detectors do auto GB but never for a PI.Originally posted by eclipse View Post
Can you please describe how this circuit would auto GB?
One of the key and tricky parts of auto GB is the Time constant for the GB adjust. If too fast then it adjusts out target response. if too slow then doesn't track changing ground conditions. I don't see any timing constant in your circuit.Leave a comment:
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How about automatic ground balance ? Is not something that I believe has been discussed.
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As I posted, there are many GB schematics and methods in the forums here.
Is the PI Polones circuit ucomtroller based?
If so then check my HH2 thread on the 3-sample GB method.
The other common method is another integrator and two more sampling switches to create a GB 'channel'.
This is then subtracted from the 'main' detection' channel. TDI, SD2000, etc use this method.Leave a comment:
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is there no separate schematic specifically pi? because I modified pi polones in the frequency section to be sensitive to gold, and the results are satisfactory, I just need to add GB for my deviceLeave a comment:
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Many in this forum.
First check the TDI schematic.
Then there are mods for the MPP and maybe the Surf PI.
Last is the firmware approach I used in my HH2. Easiest if all timing is done with a ucontroller but could be done with hardware timing (just messy).Leave a comment:
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Ground balance
does anyone have a ground balance schematic for pi
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