Hal:

I have heard others describe them (tv 75/300 baluns) as a normal, albeit
small, toroid--I don't know, would have to get some and open 'em
up--sounds to me like all sorts of designs could be being used....

But, if you look at the end of a binocular core, it does indeed have a
outline much line a figure 8... however, all I have ever heard 'em
called is binocular cores.... I have "duplicated" this design with two
toroids, side by side before (and winding through "one side" of each
independent core, touching at a "side" on each toroid--kinda hard to
describe), and seemed to work for my purposes--but since I haven't seen
anyone else doing it--so wouldn't recommend it at this point unless you
like to experiment... have purchased binocular cores for use in mosfet
linears before, they are out there...

Warmest regards,
John
"Hal Rosser" wrote in message
. ..
excuse my inexperience - what do you mean by "binocular core" ?
is that like a figure-8 ferite core ?
One that I opened up used a ferrite bar about twice the thickness of a
toothpick.



"John Smith" wrote in message
...
I never paid much attention, now that you mention it though, I seen
one
busted open once... this particular one had a binocular core...