After numerous brief power outages here causing problems with my
GPS-monitored OCXO, I finally put everything critical on a couple of
UPS's (APC-400). Noticed switching noise on 137 Khz when AC plugs
were pulled for a test but not otherwise. Overnight I turn computers
off except for a little netbook that runs the grabber. If power
should fail its battery is good for a couple hours at least and
laptops/netbooks seem to be very well shielded and contribute
negligible noise compared to a desktop. You might consider getting a
netbook (probably for less $ than a good UPS).
Thanks for your Alaska snapper - was watching it yesterday looking for JA7NI.
73,
Bill VE2IQ
At 08:01 AM 1/6/2012, Laurence wrote:
Id be interested if anyone has any thoughts or results from finding
an effective and noise free at LF/MF PC sized 30 min UPS -Ive used
laptops in AK in the past but have gone "tower" for the past year on
one of the systems but the AC supply in Alaska is proving rather
unstable, (its been off three times overnight with the weather again)
Im living in a ranch style house so dont have any Faraday cage
advantage effects from rebar/brick/block - what noises are produced
sadly go straight out to the antennae. Im mulling over a purchase
and would like (I think) a pure sine wave version...
thanks Laurence
|
