Will ferrite cores make a good output transformer?
kt Chan
I saw ferrite core being used for power transformer at 25KHz. Will it
work at 50Hz?
What will be wrong? How about making output transformer with a big
ferrite core.
K.T.Chan
Patrick Turner
> Hello
> I saw ferrite core being used for power transformer at 25KHz. Will it
> work at 50Hz?
Most probably not.
>
>
> What will be wrong?
Size of core and turn nunbers
> How about making output transformer with a big
> ferrite core.
You can use toroidal power transformers for audiosometimes, but the
bandwidth is not always wide enough.
And the primary inductance is never enough for tube operation,
unless you have a large number of tubes.
I tried all this, and got knowhere.
Patrick Turner.
>
>
>
> K.T.Chan
kt Chan
What about power transformer with ferrite core?
Iron core have larger B value per area, will large area of ferrite core
have the same B?
Tunes per volt can be adjusted to 50 Hz, but window for winding is a
problem.
I would like to to use ferrite core for a impedance transformer, did you
touch that part?
K.T.Chan
Tim
> Iron core have larger B value per area, will large area of ferrite core
> have the same B?
> Tunes per volt can be adjusted to 50 Hz, but window for winding is a
> problem.
> I would like to to use ferrite core for a impedance transformer, did you
> touch that part?
I think the basic problem with ferrite cores (and the reason that it is used)
is that they aren't very conductive, magnetic-flux-wise. But that's why they're
good for anything above 20kHz - the low permeability keeps it from saturating
at the higher frequencies (umm, do I have this right?), hence it's use.
But that means that you'd need an enourmous number of turns at lower frequencies
such as 50/60Hz, or audio. Besides, I bet that if you could make an OPT from
it, it wouldn't perform too well anyway.
Tim
--
"...And 3 of them have cradle rash! How do you get cradle rash when you sleep
in a suitcase!?"
- Apu Nahasapeemapetilon
Patrick Turner
kt Chan wrote:
> MR. Tuner
> What about power transformer with ferrite core?
Ferrite cores are used for all sorts of frequencies, and the type of
ferriteshould suit the frequency of use.
All the ferrite cored 50 Hz power trannies I have seen are toroidals.
To get the turns required for a given area of cross section
you must calculate turns from the equation for the relationship
between B and voltage rms and core area and frequency.
So there are 5 things to consider, as well as the mu for iron used.
Unless you are familiar with the equations for the design,
you will be guessing, and maybe you will see smoke, and hear no music.
So I suggest a study of the subject in Radiotron Designer's Handbook,
or other more modern textbook.
> Iron core have larger B value per area, will large area of ferrite core
> have the same B?
> Tunes per volt can be adjusted to 50 Hz, but window for winding is a
> problem.
> I would like to to use ferrite core for a impedance transformer, did you
> touch that part?
Transforming impedance at audio frequencies means adding many morevariables
to achieve design correctness, and I can only advise
much more study.
Patrick Turner.
Jack Crenshaw
possible. Ferrite
is deliberately designed to be _NON_linear, with a large hysteresis. I
think it would be
a terrible idea.
Jack
kt Chan <ktc...@hk.gin.net> wrote in message
news:3B51C1D3...@hk.gin.net...
NealK811
frequencies,and generally start to become useful somewhere north of 15 to 30
kHz.
There are ferrite-like products useful at power and audio frequencies. I
believe a European mfr. perhaps Philips/Norelco, Dynacord, or Hohner made a MI
amp that used a composite cored output transformer. These products are not
generallly competitive with electrical steels in laminate or wound form.
Guido Tent
> I saw ferrite core being used for power transformer at 25KHz. Will it
> work at 50Hz?
No, it won't, as ferrites do not show sufficient permeabillity at low frequencies.
> What will be wrong? How about making output transformer with a big
> ferrite core.
Increasing the size does not help either....
Guido
> K.T.Chan