Harry,
That much of a voltage drop is ok (3.4 kV to 3 kV), but what were mentioning is
the chart on their website which shows it having a 1000 Vdc swing from 0 to 1
ampere. From the knee, it's kind of steep at first, then if I remember from 1/2
ampere on or so, the voltage stayed around 2800-2500 Vdc from a 3500 Vdc open
voltage. I would think that one might need to fix that graph if it isn't
correct.
Best,
Will
----- Original Message -----
From: "Harry Brown" <harryhbrown@earthlink.net>
To: "David Kirkby" <david.kirkby@onetel.net>, "amps@contesting.com"
<amps@contesting.com>
Subject: Re: [Amps] HV Switch Mode Power Supplies
Date: Sat, 25 Jun 2005 07:34:30 -0400
>
> Here's some more info on a "real" application of the Watts
> Unlimited power supply.
>
> At the VHF Dinner at Dayton this year, K5AND gave a talk on a 6
> Meter amp he designed using an 8877 for DXpedition purposes.
>
> It uses a switching supply from Watts Unlimited and the total
> weight of the amp including power supply is 20 pounds.
>
> His amp idles at 175 ma. with the plate voltage at 3.4 Kv. At full
> output, 1.5 KW, the palate current is 3 Kv and the plate current is
> 850 ma. So the voltage swing is not all that terrible when compared
> to conventional power supplies. When the amp is not on, the power
> supply is keyed off.
>
> 73, Harry, W3IIT
>
> I
> At 01:16 AM 6/25/2005 +0100, David Kirkby wrote:
>
> > Will Matney wrote:
> > > David,
> > >
> > > You are correct on the regulation. A regular transformer type
> > power supply when designed right will have a regulation
> > somewherre around 11-14%. In the case of the switching supply, it
> > looks like 30-35%. 1000 kV drop over 1 amp is a good bit of sag.
> > >
> > > Best,
> > >
> > > Will
> >
> > I would have thought that cause serious non-linearity problems on SSB.
> >
> >
> > Having gone to a switch mode design, I would have thought they used some
> > feedback to keep the voltage constant. But it seems not. Given the line
> > voltage will probably sag too at 2.5kV, you can rekon on over a kV drop
> > in practice.
> >
> > I assume you mean 1kV sag, or 1000V, and not 1000kV !! Reminds me of a
> > lecturer I know who got fed up with the cleaners moving his equipment
> > that worked from 12V. So he decided to put a sign on it
> >
> > "Danger, 1200000 uV"
> >
> > Apparently nobody touched it any more.
> >
> > >
> > > ----- Original Message -----
> > > From: "David Kirkby" <david.kirkby@onetel.net>
> > > To: "amps@contesting.com" <amps@contesting.com>
> > > Subject: Re: [Amps] HV Switch Mode Power Supplies
> > > Date: Fri, 24 Jun 2005 00:39:13 +0100
> > >
> > >
> > >>Steve Thompson wrote:
> > >>
> > >>>Winfried Kriegl wrote:
> > >>>
> > >>>
> > >>>>http://www.wattsunlimited.com
> > >>>>have a 2500W SMPS. Works fine.
> > >>>
> > >>>Looks very nice.
> > >>
> > >>But look at the regulation (or lack of).
> > >>
> > >>http://wattsunlimited.com/_wsn/page3.html
> > >>
> > >>
> > >>--
> > >>David Kirkby,
> > >>G8WRB
> > >>
> > >>Please check out http://www.g8wrb.org/
> > >>of if you live in Essex http://www.southminster-branch-line.org.uk/
> > >>
> > >>
> > >>_______________________________________________
> > >>Amps mailing list
> > >>Amps@contesting.com
> > >>http://lists.contesting.com/mailman/listinfo/amps
> > >
> > >
> > >
> >
> >
> > --
> > David Kirkby,
> > G8WRB
> >
> > Please check out http://www.g8wrb.org/
> > of if you live in Essex http://www.southminster-branch-line.org.uk/
> >
> >
> > _______________________________________________
> > Amps mailing list
> > Amps@contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
> >
> >
> >
> > --
> > No virus found in this incoming message.
> > Checked by AVG Anti-Virus.
> > Version: 7.0.323 / Virus Database: 267.8.0/27 - Release Date: 6/23/2005
>
>
>
>
> No virus found in this outgoing message.
> Checked by AVG Anti-Virus.
> Version: 7.0.323 / Virus Database: 267.8.0/27 - Release Date: 6/23/2005
>
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
--
___________________________________________________________
Sign-up for Ads Free at Mail.com
http://promo.mail.com/adsfreejump.htm
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|