
Home  Forums  Rules  Articles  The diyAudio Store  Gallery  Blogs  Register  Donations  FAQ  Calendar  Search  Today's Posts  Mark Forums Read  Search 
Everything Else Anything related to audio / video / electronics etc) BUT remember we have many new forums where your thread may now fit! .... Parts, Equipment & Tools, Construction Tips, Software Tools...... 

Please consider donating to help us continue to serve you.
Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving 

Thread Tools  Search this Thread 
29th July 2002, 12:17 PM  #1 
diyAudio Member
Join Date: Jun 2001
Location: Flanders, Belgium

How to make my own inductors?
Hi all,
can anyone tell me how I can simply make my own inductors to place in series with the load of a dimmer? *)how many turns? *)is a metal "?kernel?" needed? (I don't know if this is the right word) thanks, HB. 
29th July 2002, 02:10 PM  #2 
diyAudio Member
Join Date: Feb 2002
Location: Richmond, VA.

Hi hugobross,
There are two types of inductors one can have: Air core and Iron (or some other metal) core. Air core inductors offer the user a lower chance of saturation. The price one pays is one needs to make them larger and with many more turns. Iron core OTOH allows one to make efficient smaller inductors. But they can saturate, or reach a peak, sooner. Now, the kind of inductor you need depends on the application. You can make single layer coils, or multilayer coils. The following equation (and there is another that many will quote. This one I got from a book I have from the 70's) is for a single layer coil: L=N^2Aµµ0/l Where: L = inductance N = number of turns A = cross sectional area of coil form (inner diameter) µ = permeability of core (air = 1, iron = 10005000) µ0 = absolute permeability (1.26 x 10^8) l = length of coil Rework it to find out how many turns for a single layer coil, knowing the dimensions (length, cross sectional area, air or iron) and one comes up with this (SqRt = Square Root): N= SqRt (Ll/Aµµ0) I had reworked the equation to work for me for multilayer coils, AKA pi windings. I surmised that it was called pi winding because when I did my experiment to figure out an equation for it, Pi was part of the factor. The following are for air and iron cores respectively: N= (SqRt (Ll/Aµµ0)) / (Pi/2) (for air core) N= SqRt (Ll/Aµµ0) * (1000*Pi) (for iron core) As things go, these equations aren't perfect, and one would need an inductance meter to add or remove windings to get exact inductances. But this gets you very close. I know, because when I needed to rebuild an oscillator coil for an antique radio, it brought me to within two turns of exact inductance. Hope this helps. It would help you to also read up on what inductors do and how they do what they do before going any furhter. Gabe
__________________
Gabe CGV Electronics Home of the CGV300B amplifier on a budget 
Thread Tools  Search this Thread 


Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Make it worse to make it better???  moray james  Planars & Exotics  23  12th May 2008 12:08 PM 
How to make power inductors  Mrs.Magura  Pass Labs  53  5th February 2008 11:54 PM 
How make make a microchip, from a program?  multiplexor  Everything Else  1  20th February 2004 02:24 PM 
New To Site?  Need Help? 