The "Cathodyne", or concertina, phase splitter seems to be a perennial
source of interest.
I looked up a couple of long threads that appeared on this newsgroup in
1999 and 2001. I also did a google search and found postings on various
forums.
There has been confusion about how it works for some time, and explanations
have been published (e.g.,
www.aikenamps.com/cathodyne.pdf) since the early
days of vacuum tube audio.
Eminent persons have thought first one way, and then the other.
Henry Pasternack in one of those long threads asked:
"How can it be that the outputs of the split-load phase splitter have
different impedances, yet the signal amplitudes track one another as the
load resistances vary equally?"
I haven't been able to find a truly detailed analysis, so I decided to do
one myself. I hope I have made it clear and persuasive enough to clear up
some of the confusion.
I posted an analysis with only DC conditions a couple of days ago. I have
now done another analysis with capacitive loading applied to the outputs.
The results are in 4 .gif files. The first shows the method of analysis,
and the next 3 show some results with different capacitive loadings.
The image files have been posted in alt.binaries.schematics.electronic and
in alt.binaries.pictures.radio.