I suggested a scheme to sense magnetic fields that is technically sound. AND does not require any complex electronics.

 

A GoodQuestion: How to sense a constant magnetic field wirhan AC coupled amplifier. And how to do it simply!
Since the voltage generated by a coil is due to the CHANGING magnetic flux, the simple way is to quickly invert the coil while it is still in the magnetic field. That will produce a thump in the sound from the speaker, rapid flipping the coil back and forth will producea series of thumps. The stronger the field the louder the thumps.

A coil , turning at a constant speed?

 

A coil flipped back and forth. The alternative is some form of flux-gate system, which gets complicated in a hurry.

ALSO, a switch to allow checking for electrostatic fields, not just electromagnetic fields.

 

is this the sort of thing the op is looking for
https://www.amazon.co.uk/30-20000Hz...sc=1&msclkid=42e669a836e0146df305004903d9adb8

 

I was not able to see a price for that item

 

I was not able to see a price for that item

It shows us just under GBP 11, about USD 15 I think

 

That inexpensive device was priced at $21.72 USD. But it has only 3 LEDs as indicators, so it is not relevent to this discussion. A similar device, with an actual meter, is priced quite a bit higher, at an actua,l legitimate, seller location.
Given that no actual sensitivity level is mentioned, VALID comparisons are not possible.

 

That inexpensive device was priced at $21.72 USD. But it has only 3 LEDs as indicators, so it is not relevent to this discussion. A similar device, with an actual meter, is priced quite a bit higher, at an actua,l legitimate, seller location.
Given that no actual sensitivity level is mentioned, VALID comparisons are not possible.

Wow
Two dollars to the pound. . that's a terrible exchange rate.
Has the op stated what they want as an output ?
Are they driving LEDs or a meter or a scope or what ?
As to is it relevant to the type of research the op is doing , we await their response .
Personally , it's opened up an area of knowledge on ghosts I was not aware of.
Were you aware of ghosts detectors @MisterBill2 before, what experience do you have in ghost detectors ?

 

Wow
Two dollars to the pound. . that's a terrible exchange rate.
Has the op stated what they want as an output ?
Are they driving LEDs or a meter or a scope or what ?
As to is it relevant to the type of research the op is doing , we await their response .
Personally , it's opened up an area of knowledge on ghosts I was not aware of.
Were you aware of ghosts detectors @MisterBill2 before, what experience do you have in ghost detectors ?

Most of the gohsts that I have seen have been on video screens, not live or in person. I have not even investigated any ghost-detection systems, as no potential clients have asked about "ghost detection systems." WHAT sort of physical properties would such a system sense??

 

Most of the gohsts that I have seen have been on video screens, not live or in person. I have not even investigated any ghost-detection systems, as no potential clients have asked about "ghost detection systems." WHAT sort of physical properties would such a system sense??

You say most of the ghosts you have seen are on video screens .
What were the none video screen ones like ? How did you perceive them ?
I've never experienced the none screen ones personally.

 

You say most of the ghosts you have seen are on video screens .
What were the none video screen ones like ? How did you perceive them ?
I've never experienced the none screen ones personally.

Video screen ghosts seem to be slightly delayed portions of the video signal, offset in time from the synch framework.
Non-video screen ghosts tend to be perceived at the outter edge of peripheral vision, and never clearly. And always under conditions of poor lighting and nobody else around.

 

Video screen ghosts seem to be slightly delayed portions of the video signal, offset in time from the synch framework.
Non-video screen ghosts tend to be perceived at the outter edge of peripheral vision, and never clearly. And always under conditions of poor lighting and nobody else around.

Yep
Seen plenty of those TV one in the days of analog TV , and different reflection paths .
But you said most , as in you had seen ghosts not from the TV , so wondering what experience you had with these as I've not .
Interesting .

 

Yep
Seen plenty of those TV one in the days of analog TV , and different reflection paths .
But you said most , as in you had seen ghosts not from the TV , so wondering what experience you had with these as I've not .
Interesting .

Those other sightings would tend to happen when I was servicing a machine system in an auto plant when there were no folks there and most of the lights were out, except for where I was working. So with all of the machines OFF and all of the workers gone, it was very quiet. Totally still! LIke a closed library on a Sunday morning! And yet, I would, on several instances, see a figure hurrying down an aisle in the dim light but not making any sound at all. Thefootsteps of the securty guards I could hear even when they were trying to be silent, and walking slowly. But the bustling figures inn the distance made no sounds. When I asked the securty guards about it, they told me that "of course the plant was haunted", because "over the years a few had died there." Mostly, not from accidents, or foul play.
None of the unknown entities ever approached, although it did seem at one time that one was watching me.

 

Seen plenty of those TV one in the days of analog TV , and different reflection paths .

Fun fact - while the most common type of video ghost was caused by incident and reflecting path length signal merging. it was/is possible to have visible ghosting in a 100% non-broadcast, all-cable system.

ak

 

Fun fact - while the most common type of video ghost was caused by incident and reflecting path length signal merging. it was/is possible to have visible ghosting in a 100% non-broadcast, all-cable system.

ak

The most recent instance of ghosting thatI came across was caused by an evidently poor quality VGA extension cable tied to a 19 inch computer monitor. changing to a direct connection, without that extension cable, totally removed the ghosting effect. The incident certainly was a learning experience for a few people.