Comments on: A simple low frequency magnetic field flux meter

By: admin

admin — Sun, 03 Jan 2010 19:41:19 +0000

@St.Jimmy
Hello, yes, correct : place 60 where 50 is in my case.
Also, Bcos(2pi f t) equals 10 exp-6 Tesla
You should get a total of 110 turns with my same plastic JVC core.
Best
A.

By: St.Jimmy

St.Jimmy — Sat, 02 Jan 2010 02:57:16 +0000

I have that same antenna, so in America, I’d just plug 60 in where the 50 is, right? So, 500*10^-6/2*3.141*60*(.1*.12)*B cos(2*3.141*60*t), or .00000500/4.52304*B cos(376.92*t), right?
But, I don’t understand what B and t are. Can you help me out?

By: admin

admin — Thu, 05 Nov 2009 11:40:17 +0000

@Munsif Ali thanks for writing.
i’m not sure what’s the picture you mention, nonetheless I made some research at the Canadian Space Agency and found a picture ( http://www.asc-csa.gc.ca/eng/educators/resources/radarsat2/part1_background.asp ) that might be like the one you mentioned.
To me the magnetic flux is the product of component of the magnetic field perpendicular to the surface of the loop (coil) (the blue sinusoidal varying lines in the second picture from top) by the surface of the coil (crf wikipedia http://en.wikipedia.org/wiki/Magnetic_flux ) . In our case the coil is placed verically and perpendicularly to the blue lines and the flux is the product of total magnetic filed entering the coil times the area of the coil.
Hope this helps
Thank you
A.

By: munsif ali from pakistan

munsif ali from pakistan — Mon, 02 Nov 2009 12:29:19 +0000

hi, I am munsif ali from pakistan. while studying electro magentic waves , I got an illustration about magnetic and electric field, composing electro magnetic waves. from canadian space agency website, One page explained emmission of electro magnetic waves. and an example of a metal wire was shown.

The definition of flux goes as follows, It is the rate of flow of fluids, energy and particles,

In the illustration, it was explained that when a current oscillates at 5.4 GHZ it produces electromagnetic waves, made up of magnetic field and electric field. where as movement of electrons was illustrated separately in green dots., now I have a question, with regard to illustration of canadian space agency regarding electromagnetic waves, how will you explain magnetic field flux. in that illustration. kindly contact on my e.mail.

By: Bryan

Bryan — Tue, 16 Jun 2009 08:58:54 +0000

Oh… Also just to fill in the blanks. It is named as a search coil, used to detect the total flux of the surface of the magnets… Static field measurement is what i require anyway.

By: Bryan

Bryan — Tue, 16 Jun 2009 08:55:26 +0000

Thanks for tip yah… Let me bust my brains.

By: admin

admin — Wed, 03 Jun 2009 07:16:36 +0000

@bryan, almost forgot : the gauge can be any reasonable gauge, it doesn’t need to be a fine As possible, just strong enough not to break when winding around the loop. The number of turns can be calculated with the formulas and depend on the loop.
Ciao
A.

By: admin

admin — Wed, 03 Jun 2009 07:14:06 +0000

Ciao Bryan, the circuit measures variable fields. Your magnets must be part of variable magnetic circuit. I might be missing something here of course.
Ciao

By: Bryan

Bryan — Tue, 02 Jun 2009 10:43:44 +0000

Hi, Your post of the low frequency fluxmeter is good. I am trying to do up a project. To read 2 permanent magnets, ferrite and neodynium. Compare them when heated up to 30-40-50 degs.

Using your schematics, can i safely read values from a search coil of maybe 80 turns? The finest wire i can get is from a relay, but i don’t know what is the guage size.

Please do help me.

By: cooperman

cooperman — Sat, 12 Jul 2008 10:40:58 +0000

Brilliant.
Well presented article describing a simple solution to a relatively complex measurement.
Cooperman.