[RFI] UPS suggestions

[Cortland Richmond]

This may help some 105/110/120VAC-area readers decide how to handle 
short-term power needs.

I would not expect all but the very most critical equipment to need an 
online always-on UPS.  I am typing on a tower-type computer (400W power 
supply) plugged into a standby Xantrex 400 watt sinewave inverter(1) 
connected to 200 AH of golf-cart lead acid batteries. An IOTA 55 Amp 
charger(2) keeps the batteries topped off.  That does have some discrete 
RFI, but not on frequencies I use normally, and rarely bothers anything 
when when the battery is charged, The Xantrex switches rapidly and draws 
current only when the power is off; I have used it for Field Day 
operations and not even noticed when the generator ran out of gas.   
(However, I advise anyone operating that way not to use their car 
battery to run the station.)
1) 
http://www.xantrex.com/documents/Power-Inverters/XS400/06222006JS_XS400%20Sine%20Wave%20Inverter.pdf
2) http://www.iotaengineering.com/dls55.htm

Power has gone off a few times here, but the switchover is fast enough 
to be unnoticeable except that only one CFL desk  lamp stays on.

I recently found a small Belkin UPS meant for AT&T U-verse systems  at a 
local thrift shop, which I am keeping charged up to run other small 
electronics that need either AC or "wall wart" power.
http://cache-www.belkin.com/support/dl/p75319-b-bu3dc000-12v.pdf

Cortland
KA5S

On 3/8/2013 1010, Pierfrancesco Caci wrote:
> ...should I be lured by an on-line, sinusoid waveform UPS, or am I likely to get lower RFI from a
> line-interactive one that doesn't keep the inverter on at all times?
>
> The UPS would be used only for the PC, Monitor, switch and maybe the
> printer if there's a filtered, non-protected port.
>