[MrTallyman]

On Tue, 07 May 2013 16:11:06 GMT, (Don Pearce) wrote:

On Tue, 7 May 2013 03:46:38 -0700, "William Sommerwerck"
wrote:

Construction of these transformers doesn't have to follow the normal
rules. They don't need good linearity, so very high permeability
ferrite can be used for the core in order to get a high inductance
value. This is because the audio doesn't have to pass through the
ferrite, it bypasses it.

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I know of no transformer type in which the signal "passes through" the core
material.

Nit-picking the terminology? In a transformer, the core is used to
couple the signal from the primary to the secondary. In this sense the
signal "passes through" it. In the series balun the only signal that
interacts with the core is the unwanted common mode or single sided
signal. This is generally of such a low value that it has no chance of
causing sufficient field strength to cause non-linearity.

d


An inductor is NOT an inductor UNLESS the TURNS pass THROUGH the core.
(where a ferrous "core" is involved) An air core type inductor probably
has different behavioral models for its operation (they do), but the
turns are counted within a toroidally wound structure, and on the inner
walls of other shapes of "core".

The turns count is exactly the number of turns that appears WITHIN the
core.

A transformer cannot work unless BOTH WINDINGS are WOUND AROUND and
THROUGH the CORE.