[AMPS] Transformer ++

[jeff millar]

5 KW switcher? no.  But switching power supply to power digital logic
in communication receivers, yes. It's not a trivial task, that's true, but
it's
not magic either, design works.   The primary drivers on design consist
of FET's,Choke, shielded package, and input/output filtering
components.

Moving the switching frequency around saves money on shielding
and fitering, it's just the cheap way out.

jeff, wa1hco

----- Original Message -----
From: Alex Von Yonkers <avy@qwestonline.com>
To: jeff millar <jeff@wa1hco.mv.com>; <amps@contesting.com>
Sent: Sunday, March 25, 2001 6:55 AM
Subject: RE: [AMPS] Transformer ++


> Hmmm....Have you ever designed such a monster before Jeff?
> You realize you have to have variable Oscillator Frequency to be able to
> move eventual EMI from the Rx frequency. And this under Receiver Control.
> Unless you can design a real quiet (-100dBm EMI) 2-4KW switcher in the
> frequency bands of interest. This is not a trivial task :)
>
> Alex
>
>
>
>
>
> > -----Original Message-----
> > From: jeff millar [mailto:jeff@wa1hco.mv.com]
> > Sent: Saturday, March 24, 2001 9:57 PM
> > To: avy@qwestonline.com; amps@contesting.com
> > Subject: Re: [AMPS] Transformer ++
> >
> >
> > How about a switch mode power supply that drops 120-0-120 full wave
> > rectified down to 50 volts?  This will require a switcher chip, some
hefty
> > FET's and a high frequency, high power choke but no transformer.
> > Using the
> > 240 feed as a 120 each side of center and two big diodes to
> > rectifiy it will
> > produce about 150V.  The switcher chip will track the 120 Hz power
ripple
> > fairly well, just use enough filter C to hold the voltage to about 60-70
V
> > minimum.
> >
> > If you're interested, I can help with figuring the values and selecting
> > parts.
> >
> > jeff, wa1hco
> >
> >
> > ----- Original Message -----
> > From: Alex Von Yonkers <avy@qwestonline.com>
> > To: <amps@contesting.com>
> > Sent: Saturday, March 24, 2001 5:07 PM
> > Subject: RE: [AMPS] Transformer ++
> >
> >
> > >
> > >
> > > Speaking of transformers. I'm building an amp based on four MRF157
> > > Transistors from Motorola.
> > > I need to build an Power Supply able to deliver 50A at 100A or two of
> > > 50V/50A. I have called several transformer manufacturers but I almost
> > > had an hearth attack when told about the prices.
> > >
> > > Any good idea?
> > > Alex
> > >
> > > PS. Do you think that there could be a market for a 2KW+ solid
> > state amp?
> > >
> > >
> > > --
> > > FAQ on WWW:               http://www.contesting.com/FAQ/amps
> > > Submissions:              amps@contesting.com
> > > Administrative requests:  amps-REQUEST@contesting.com
> > > Problems:                 owner-amps@contesting.com
> > >
> > >
> >
> >
>
>


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