Re Sensor

[Salman]

Dear Willy
I like to build toroidal sensor but the main problem is that i am not able to get the grasp on the excell sheet that give the specification of the sensors kindly guide me to construct the sensor. This is because the signal to noise ratio will be much much on the higher side so that i may not face the problems associated with the solenoid.
I would like to know about the dimentions internal external dia wire gauge in SWG. number of turns polarizing current etc

[salmam]

Re: Re Sensor

thanks for your valuable help. I have decided to go ahead with your calculation i-e

r=0.016
R=o.06
V=12
bandwith =1500
layer =12
no of turns =2865
length of wire =396
Plz let me know how much this configuration willl be helpful comparing to solenoid. Should i construct two sensors of same configuration? or single will do the job

If you recommmend two sensors what should be the winding criteria ?

Would you like to advice any thing especial which I should keep in mind wile doing winding be cause Iwill be doing all winding with my hands?

One more problem I am facing is about wire guage, in Pakistan wire is available in SWG not in AWG . H ave you any formula to convert AWS in SWG?

Finally I want to ask abut preamplifier and bandpass filter and amplifeir cct.

What cnfiguration you have used for preamplifier cct.

I want to have bandpass filter for 1890hz center frequency .

what code you are using in microcontroller for switching and displaying strength of magnetic field on lcd display

plz send me your ccts in detail

[Willy Bayot]

Re: Re Sensor

It depends what you want to do. One sensor is enough for standard field survey provided you make a precise frequency measurement process behind the amplifier chain and that you make twxo measurements at each location of the survey, one at 1 meter above ground and the next one at 2 meters above ground.
You could also make two complete separate PPM's, one at a fixed location and one to make the actual survey. This helps to remove the diurnal variations of the magnetic field.
You could also make a gradiometer configuration also with two separate systems but with the two sensors mounted on the two ends of a stick. Finally, you could make a differential PPM (à la mode Phil Barnes) with two sensors connected in series-opposition.
For the table of SWG-AWG, I sent it to you by mail.
For the rest of your questions, we are not yet ready to publish our circuits and algorithms.
I think that you could start with the circuit of Phil or the one of Jim Koehler. They should be OK.

Willy

[Salman]

Re: Re Sensor

HI,
Well I have the amplifier working now the main problem is the tunning of sensors you told once but please in a little more detail.
because the enviorment where we are testing is very noisy so we have to take the setup in open air now the problem there is that we dont have an AC line so can we test it on labtop will it be sufficient.
The detail of the tunnning of sensors in more detail is required please provide help in this regard