SBG-PID

[6666]

Anybody made it yet?
Any video?
I am too busy in this period, unfortunately i can't have time to pay on this.
But i would really like to see if somebody make success with this detector.

Hi I have been trying but time poor, can your pcb file produce gerber files ? if we could get some pcb's made it would be good.

[Carl-NC]

I completely forgot, there was a quiz question back in #151:

"This design may not need traditional EFE sample subtraction. Why? (This is a quiz question. Hint: the PI circuits in ITMD also did not have a late EFE sample, yet do OK without it.)"

C3 capacitively couples the decay signal to the preamp and provides high-pass filtering. EFE is a slower signal than a target response so it is possible to decently suppress it this way. Not as good as sampled-subtraction, which is also not as good as a bipolar design. I would suggest a bleed resistor added to C3. If not C3, then the HPF function of the integration stages will provide EFE rejection.

[DonCaffeDelaSkobalj]

Another bulgarian rubbish in forum's room !!


Not similar like "supreme" bulgarian Pi design but has connection with pulse technolgies.

Let's read what Tesla had said about the "greatest" inventor Marconi.


Tesla:

"I may say that a lot of liberties have been taken. For instance, a man fills this space [break D] with hydrogen; he employs all my instrumentalities, everything that is necessary, but calls it a new wireless system?the Poulsen arc. I cannot stop it. Another man puts in here [referring to space between self-inductive lines L L] a kind of gap?he gets a Nobel prize for doing it. My name is not mentioned. Still another man inserts here [conductor B] a mercury[-arc] rectifier.....".

"If these men knew what I do, they would not touch my arrangements; they would leave my apparatus as it is. Marconi puts in here [break D] two wheels. I showed only one wheel; he shows two. And he says, "See what happens when the wheels are rotated; a wonderful thing happens!" What is the wonderful thing? Why, when the teeth of the wheels pass one another, the currents are broken and interrupted. That is the wonderful thing that happens? So, in this way, invention has been degraded, debased, prostituted, more in connection with my apparatus than in anything else. Not a vestige of invention as a creative effort is in the thousands of arrangements that you see under the name of other people?not a vestige of invention. It is exactly like in car couplings on which 6,000 patents have been taken out; but all the couplings are constructed and operated exactly the same way. The inventive effort involved is about the same as that of which a 30-year-old mule is capable. This is a fact".

[Andi68]

Well, can you construct a better circuit and introduce it here?

[green]

I completely forgot, there was a quiz question back in #151:

"This design may not need traditional EFE sample subtraction. Why? (This is a quiz question. Hint: the PI circuits in ITMD also did not have a late EFE sample, yet do OK without it.)"

C3 capacitively couples the decay signal to the preamp and provides high-pass filtering. EFE is a slower signal than a target response so it is possible to decently suppress it this way. Not as good as sampled-subtraction, which is also not as good as a bipolar design. I would suggest a bleed resistor added to C3. If not C3, then the HPF function of the integration stages will provide EFE rejection.

Tried recording EFE signal at amplifier out. Connected 8inch mono coil to my bench circuit and swung it while watching scope. How I swung the coil had a big effect on amplitude. Is it possible to swing the coil for no EFE signal? What has to happen to cause an EFE signal?

[waltr]

Tried recording EFE signal at amplifier out. Connected 8inch mono coil to my bench circuit and swung it while watching scope. How I swung the coil had a big effect on amplitude. Is it possible to swing the coil for no EFE signal? What has to happen to cause an EFE signal?

EF effect is due to moving a conductor through a magnetic field.

This is covered in Physics 102 so good place to search for the Physics answer details.

Basics:
If the magnetic lines of force are parallel to the conductor then moving the conductor will not produce a current to flow.
It is when the Magnetic lines cut across the conductor that current will flow if the conductor moves.
The maximum current flow for uniform magnetic flux and conductor velocity will be when magnetic lines are perpendicular to the conductor and reduce at smaller angles.

[dbanner]

[Davor]

What you fix with a late EF sample is a collective sum of all offsets, but motion filter takes care of those as well. A detail that is not fixed by motion filtering is 1/f noise, which is effectively fixed with EF pulse.

[Carl-NC]

What you fix with a late EF sample is a collective sum of all offsets, but motion filter takes care of those as well. A detail that is not fixed by motion filtering is 1/f noise, which is effectively fixed with EF pulse.

Excellent point. Bipolar pulsing also fixes 1/f noise.

[green]

Hi dbanner, what happened to your reply? Don't know if it was correct but you at least tried to answer the question. Maybe swing should have been move the coil through the earth field. If the coil was mounted on a slide table that moved back and forth +-1m that could be aimed in any direction, North South, East West, horizontal vertical or any direction in between would there be an EFE signal. My guess is no, searched Physics 102 but haven't found the answer yet. Guess is based on observations of a crude experiment

[Davor]

Excellent point. Bipolar pulsing also fixes 1/f noise.

True. It does not spoil ferrous response, so it is superior to EF sample method.

[scs]

To DonCaffeDelaSkobalj
" Another bulgarian rubbish in forum's room !!"
I notice that garbage is only in your head.

[green]

Hi dbanner, what happened to your reply? Don't know if it was correct but you at least tried to answer the question. Maybe swing should have been move the coil through the earth field. If the coil was mounted on a slide table that moved back and forth +-1m that could be aimed in any direction, North South, East West, horizontal vertical or any direction in between would there be an EFE signal. My guess is no, searched Physics 102 but haven't found the answer yet. Guess is based on observations of a crude experiment

Before the experiment I might have replied yes. Still don't know which is correct. Including scope picture of trying to measure EFE. Signal was less if pivot was N S. Holding the coil vertical, signal appeared to be higher amplitude when rocking coil, rocking N to S or E to W appeared the same. Little or no signal when moving coil back and forth. Signal at amplifier out is picking up a lot of EMI from scope at amplifier out so it's hard to see a small change. Would be hard to keep coil in same position without a slide table.

[scs]

The scheme works steadily without noticeable impact
from the field of the earth.

[6666]

Thanks a lot!
Bravo for spotting those!
Here is finally corrected:

Ivconic could you please post the gerber files thanks, and I will try and get some PCB's made