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Output transformer for Philco 39-17
#5

Well, to make it easier a bit:

The impedance of the VC is never lower than the guaranteed "minimum impedance" which is the DC resistance of the coil.
Then for calculations is so called "nominal impedance" is used which loosely describes the behavior over most of the audio span.
This is given as 1.15*Zmin so it is about 15% higher than measured DC resistance.
It is imprecise but quite OK for transformer pickup.

In any case it is NOT going to be lower than the DC resistance.

So, DC ohming out is still useful.

PS> Again, this works for a single speaker. Not for acoustic systems that have crossovers and that complicates the heck out of calculations. But in this case it is the single speaker.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.


Messages In This Thread
Output transformer for Philco 39-17 - by Sourbone - 05-05-2016, 10:53 AM
RE: Output transformer for Philco 39-17 - by morzh - 05-05-2016, 02:56 PM



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