[ARC5] [Boatanchors] [Milsurplus] A Super-Easy 95 Volt B+ Supply for Your Projects.

[D C _Mac_ Macdonald]

Now all I have to do is to figure out where to get the 18-75 VDC to drive it!  How well do ARC-5 and SCR-274-N receivers work on 96V? 
 
* * * * * * * * * * * 
* 73 - Mac, K2GKK/5 * 
* (Since 30 Nov 53) * 
* Oklahoma City, OK * 
* USAF, Ret (61-81) * 
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> Date: Fri, 20 Dec 2013 16:29:14 -0800
> From: jfor at quikus.com
> To: arc5 at ix.netcom.com
> CC: boatanchors at mailman.qth.net; arc5 at mailman.qth.net; milsurplus at mailman.qth.net
> Subject: Re: [Boatanchors] [Milsurplus] A Super-Easy 95 Volt B+ Supply for	Your Projects.
> 
> It looks like an interesting part.
> 
> How much EMI does it put out? I'd guess it's pretty noisy.
> 
> Also, it looks to be an end-of-life part. I've been burnt by those in the
> past. They can easily become unobtanium, or very expensive.
> 
> My inclination has always been to use relatively low frequencies (<5kHz)
> in switchers. Yes, it does make them somewhat bigger and heavier, but the
> EMI is much reduced, since you can use longer switching times.
> 
> FWIW,
> 
> -John
> 
> =================
> 
> 
> 
> > As ya'll know, I've had good luck working with monolythic
> > DC/DC converters for powering projects.
> > Many of them aren't useful for us, having outputs like 5V etc.,
> >  but there is a current listing that will fit many projects.
> > I bought a couple for testing.
> > They were quiet inexpensive- $8 each.
> >
> > http://www.ebay.com/itm/160775207820
> >
> > A spec sheet is at:
> >
> > www.murata-ps.com/data/power/bwr15-20wa-series.pdf
> >
> > While the converters are speced for 18 to 75 volts DC in
> > to produce an isolated-from-the-input dual output of + and - 48 Volts,
> > I've tested these down to 10 Volts in and they still worked fine.
> > The two output supplies have a common "ground."  By leaving this "common"
> > open and connecting the + output as B+ and the - output to ground
> > (12 volt input common),
> > I have a 95 VDC B+ supply from 12 or 24 Volts in.
> > I tested it by powering-up a "hammed" BC-454 receiver.
> > It worked well but does have some low-amplitude""birdies"
> > on the output.  I did not do any RF filtering during the tests.
> > I have filtered other DC/DC converters like this with ferrites and
> > that took care of the birdies.  Smarter people than me will have
> > ideas on this.
> > I'm ordering some more.  Very useful.
> >
> > 73 DE Dave AB5S