[hpsdr] warning stupid newbie question

[ke9h at austin.rr.com]

Don:

The power supplies should be within 5 percent of the target voltage and
reasonably quiet, with respect to ripple, and switching noise if you are using
switching power supplies.  I don't have a spec on "reasonably quiet", but
I would guess something like, less than 50 milliVolts at audio frequencies
and down, and a lot less than that at higher frequencies.  Otherwise, you will
get birdies up and down the receiver at harmonics of the switching frequencies.

You really don't need -12 V, since it only powers a serial port on Ozy that
is not currently being used.

+12 and +5 is all that you need for running Ozy/Penelope/Mercury in the
current configuration.

--- Graham / KE9H

==
---- Don Latham <djl at montana.com> wrote: 
> ***** High Performance Software Defined Radio Discussion List *****
> 
> OK, I built the Atlas backbone. Put on 3 different power supplies. All
> read funny on +12 from 10 to 11.5 volts, on -12 all read about -10 volts.
> Typical? Will these ps's do the job?
> Thanks for helping someone too lazy to look in the archives...
> 
> 
> -- 
> Dr. Don Latham AJ7LL
> Six Mile Systems LLP
> 17850 Six Mile Road
> POB 134
> Huson, MT, 59846
> VOX 406-626-4304
> www.lightningforensics.com
> www.sixmilesystems.com
> 
> _______________________________________________
> HPSDR Discussion List
> To post msg: hpsdr at hpsdr.org
> Subscription help: http://lists.hpsdr.org/listinfo.cgi/hpsdr-hpsdr.org
> HPSDR web page: http://hpsdr.org
> Archives: http://lists.hpsdr.org/pipermail/hpsdr-hpsdr.org/


 1233241287.0