I am looking for a simple excel spreadsheet to calc. transformers, no. of turns, power etc.

The analysis of t-formers has gotten a little easier since some one figured out to reflect the secondary parasitics over to the primary (or vice-versa) so they could be lumped and the t-former sorta modeled as an inductor.  As far as n turns primary, that is a trade-off between leakage inductance and parasitic capacitance, as well as mechanical and economic factors. 

There are all sorts of core materials that are used in transformers because there are all kinds of frequency and bandwidth regimes in which they are employed.  Broadband transformers are different.  Signal transformers are different than power transformers.  There are T-line transformers.  Coupling transformers for impedance matching. . .

Different kinds of magnet wire are available, square wire, litzendrath wire. . .

There are all kind of cores and winding schemes. . .

I am proud to state as a citizen of the four-star city, that the first commercial operation to make transformers in large quantities was Thoradson in Chicago.  Between the turn-of-the-century and the advent of WWII we were a high-tech capital.

Transformers are darn interesting, both on paper and in the meatspace.  As a prior poster indicated you aren't gonna become a T-former wonk in a day.

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The analysis of t-formers has gotten a little easier since some one figured out to reflect the secondary parasitics over to the primary (or vice-versa) so they could be lumped and the t-former sorta modeled as an inductor.  As far as n turns primary, that is a trade-off between leakage inductance and parasitic capacitance, as well as mechanical and economic factors. 

There are all sorts of core materials that are used in transformers because there are all kinds of frequency and bandwidth regimes in which they are employed.  Broadband transformers are different.  Signal transformers are different than power transformers.  There are T-line transformers.  Coupling transformers for impedance matching. . .

Different kinds of magnet wire are available, square wire, litzendrath wire. . .

There are all kind of cores and winding schemes. . .

I am proud to state as a citizen of the four-star city, that the first commercial operation to make transformers in large quantities was Thoradson in Chicago.  Between the turn-of-the-century and the advent of WWII we were a high-tech capital.

Transformers are darn interesting, both on paper and in the meatspace.  As a prior poster indicated you aren't gonna become a T-former wonk in a day.

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