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If shielding blocks electromagnetic waves then why we use them on m.d coils
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foil/copper shield yes blocks electromagnetic waves. graphite one not. EMI freely goes through graphite lossless.
while we see poor people uses foil for coil, but doing/leaving small gap. then EMI can go through the shield but
loosen in force. very common question (FAQ) from them we get 'why i can not get good depth with my super made coil on the coin?'
that is.Comment
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After searching and reading some posts regarding interference i need to clear some thoughts. I'm mostly interested in power lines interference (high, med and low voltage lines 50hz) but also we can take in consideration other type of interference like rf transmitters, communication/electric motors from petroleum extraction systems, electric fences.
Some say pulse cycles (pps) need to be sync with alternative phase. Others say we need to avoid same or multiple frequency as power lines. Delta pulse build document says "for country with 50hz electric frequency we choose 100pps/hz). You can say "just add a potentiometer for frequency adjust and turn it until you don't get interference". But i want to understand why. I would like to add a 2 or 3 position switch for that. This type of interference it is picked up only by the coil or affect the pcb also?
I know minelab gpx4500 and vallon (with software update), for example, have the automatic noise cancelling feature. Does it scan all frequency and find the quiet one? It is the same for vlf detectors? (sov gt has noise cancel - band 1, band 2, deus had adj frequency or frequency shift, equinox has auto/manual noise cancel). This is very nice feature to implement in detectors (but of course this require mcu).Comment
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But i want to understand why.
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you can add a pot for PPS, but DP has so much pots while EVERY pot is needed to be explained for what it is
on a level of kitchen wife/pakistani guy.
imagine this work with mine english -! also, nobody does not want to do detailed report for DP assembly.
if everybody ask about interference - i opened this thread.
first information about PPS value was got from bulgarian men (there were two of them).
also, we still do not have full data on the DP coils. luck of information is born misunderstanding.
like every sensitive device DP will also not work under high voltage electric lines. lines gives very big static potencial on ground surface
and there is not direct decision how to come around it.Comment
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electrostatic field what is it. https://www.youtube.com/watch?v=pgELH03uXdg
just look. in russian but you see anyway.Comment
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