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Transformer Lam Questions

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Alright so I've been bitten by the transformer winding bug and decided to finish my plans to actually wind a pair. My goal is two SE transformers for the 6C33C tube, mostly due to the low impedance.

I have a supply of EI-150 M6 lams and have been playing with Yves' OPT calculator. In the section to pick the lamination size there are three listings for the EI-150. EI-150NA, NB, and NC. I can't find any specs for these suffixes. Does that mean how thick the stack of lams will be? EI-150NA looks to be the biggest because AFe (cm2) and the wire length both increase.

Lastly, I found a company who makes bobbins and is willing to sell me a few. http://www.foremostplastic.com/Page8.html Look at part number 5-3379 for example. Does that mean a stack 1.5" thick? Any input is appreciated.
 
This site gives a little more detail http://www.mfkbobbins.com/unterm_rec.html

You can also calculate the cross section area by ; Afe = T x S

Ah that makes sense now. On the calculator EI-150NB lists AFe as 30.1cm2. So T is 1.5" or 3.81cm. Then we can do

3.81(Y)=30.1

Y=7.90cm or 3.11"

A stack 3.11" high. NC is a stack 4.34" and NA is a stack 2.29" Odd sizes when most bobbins seem to be made to .25" increments.

Looking at the core.tbx file didn't help much :confused:

EI150NC=42.1,9.7,30,20.4,68.7,37.1
EI54=2.94,0.243,10.8,7.1,24.3,10.5
EI60=3.7,0.34,12,8,26,11.7
EI66A=4.46,0.45,13.2,9,28.7,12.8
 
Just a followup about the core data. If you edit the core data in the program the window has the names for the values listed.
 

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