[HomeBrew] Smoothing a square wave

[Diane Bruce]

On Thu, May 04, 2006 at 02:03:55PM -0400, wabate wrote:
> ** Please do NOT cross-post messages when posting to HOMEBREW **
>
> Jim,
>
> I am tackling the same problem except for a generator.  You would think
> that a generator would have a smooth sine wave.  No so.  I have not been
...
> with a HV secondary is dangerous.  I would suggest a 120v/120v
> transformer to smooth things out.  Maybe a cap on the secondary?   You

The square waves could saturate the core making it run very hot and eventually
cooking the core, I'd not recommend it. In fact, that is the same problem
you would run into with any equipment that has a transformer. It is possible
you can run anything that uses a switcher instead. The AC coming
in is rectified anyway and then switched. This should work and in fact
I have heard of it working fine. I'd be worried a bit about duty cycle
though, but if it's more of a rounded square wave it should be fine.

Obviously, what is needed is a low pass filter to get rid of the harmonics
but I shudder to think of what would be needed component wise.
Perhaps a custom wound toroid and pair of non-polarised caps.

- 73 Diane VA3DB

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- db at db.net http://www.db.net/~db