[Amps] power supply transformer

[Phil Clements]

I have a Collins 28 volt 100 amp power supply here in great condition.
Someone make me an offer I can't refuse....


(((73)))
Phil, K5PC


> -----Original Message-----
> From: amps-bounces at contesting.com [mailto:amps-bounces at contesting.com] On
> Behalf Of Michael Tope
> Sent: Wednesday, January 31, 2007 12:15 AM
> To: Tom W8JI; kg7hf at comcast.net; amps at contesting.com
> Subject: Re: [Amps] power supply transformer
> 
> 
> ----- Original Message -----
> From: "Tom W8JI" <w8ji at w8ji.com>
> 
> >
> > You should use a transformer for a few reasons (as was
> > already covered) like line surges and safety. It is against
> > code to EVER ground a neutral to anything connected to
> > something external, so the neutral has to float. You could
> > float the entire negative rail from chassis, but then the
> > issue becomes spikes from the power line into the PA and
> > harmonics from the rectifiers into the power mains. You
> > certainly could design a system that would use the power
> > mains safely and not break codes, but it would require some
> > care.
> >
> > The real problem is knowing the ESR of the transformer.
> > Certainly it isn't as low as it could be because of the fact
> > it is a control transformer, but a choke input would help a
> > lot. You could get a power factor close to unity rather than
> > the very poor power factor of a capacitor supply, so you
> > might be OK if the choke is a good one.
> >
> > 73 Tom
> >
> 
> Sounds like a good application for a switch-mode supply.
> 
> Mike W4EF..............................
> 
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps