Topband: Progress with ugly computer noise

[Bill Wichers]

A lot, probably most, of the really cheap UPSes are just switching step-up converters. The easy way to spot them is from the crazy ratings like "1000va" but only 3 amps (which should be about 360va). They sell them based on people thinking "bigger is better" even though a .36 power factor is pretty useless. I used to always think apc's .7 was misleading... The big commercial units are .8-.9.

I've personally always had good luck with the apc smartUPS line for small upses. They are sinewave output (and surprisingly good when checked w/ a scope), and pretty clean due primarily to their pseudo-ferroresonant design. I'd stay away from the backUPS line though since those aren't much different from the el-cheapo units.

Note that supposedly "bad" smartUPS upses can be found for cheap at swaps and on ebay. Almost always all that is needed is a new set of batteries to get them running again.

-Bill
[Sent using Blackberry Messaging]

----- Original Message -----
From: topband-bounces at contesting.com <topband-bounces at contesting.com>
To: TOPBAND <TOPBAND at CONTESTING.COM>
Sent: Wed Jul 04 18:14:07 2012
Subject: Topband: Progress with ugly computer noise

Be careful with UPS units as I have seen them cause more problems noise wise that computers.  A friend of mine had a really bad one he had to unplug to operate on any band.  Everything was clean once he got rid of that thing.. 73 Mike K4PI
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