Rich says:
>depends on Webers per cubic meter. If the output
>waveform is notably distorted, you have core saturation.
That generally (but not always) goes with heat in the core, too.
Of course, tiny cores can saturate at powers so low you don't notice the heat. I
worked on a project once with transformers that didn't produce distortion at
first, but as they got hot, the permeability started to drop, and that screwed
up the reflected load impedance, which upset the PA. As the permeability dropped
further, the transformer primary inductance dropped and the transistors died.
Being less experienced, I got through several pairs of (expensive of course)
transistors before catching on to what had happened........then just as I got
things more or less working, the project got canned!
Ferrite beads as parasitic suppressors (on PA tubes, as well as on low level
solid state amplifiers) are the most disappointing ferrite application I've ever
tried.
73
Peter G3RZP
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