[Milsurplus] 400 Hz transformer

[J Forster]

It's likely wound on an E-I or C (tape wound) core, but one with thinner laminations than a 60 Hz
transformer to reduce iron loss.

Here's how to roughly estimate the core size:

You know the primary voltage and turns, hence you can compute the Volts/Turn (= roughly 0.5 V/T)

If you look in a core catalog, you can find a core size with roughly that number of V/T..  BUT you
must use the data for 400 Hz or scale 60 Hz data by 400/60. [ said another way, if a core has 1 V/T
@ 60 Hz, it will have 1 V/T * (400/60) =  6.66 V/T @ 400 Hz]

You then figure out how the winding fitted in the core "window" (# of T/layer; # of layers,
insulation thickness, bobbin size, etc.)

It's not difficult, but you should read up n it a bit.

BTW, getting laminations thin enough for 400 Hz in small quantities may not be easy.

I'd either try a 60 Hz unit or search places like Fair for a 400 Hz unit.

Best,
-John

==================

Brad Latta wrote:

> I managed to find some winding details for a 400Hz filament transformer
>
> Primary, 0 to 80v, 159 1/2 turns, 19 AWG, plus a further 69 turns 80 to 115v
>
> Secondary, 13 1/2 turns of paralled 17 AWG. Now all I have to do is find a suitably sized core!
>
> While I'm here, what is Radio Filter FL-5-F (order 514-WFSCPD-42) used with, and
> Bendix Tuning meter MT-31C?
>                              Regards, Brad