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" To: "David Kirkby" , "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" > > > To: "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