[Elecraft] UPS Can Be a Noise Source

[Jim Brown]

Good observations, Lynn.  A few more. First, I failed to observe that my 
100Ah LiFePO4 battery runs ONLY my K3s. A big lead-acid from Costco runs 
other 12V gear and LED lighting. I do NOT try to provide UPS for power 
amps.  If I need them, I'll fire up the big 240V generator.

Second, a local computer guru, AE6KS, has observed that most UPS mfrs 
charge batteries at too fast a rate for good battery life. The objective 
is to have the unit ready to do it all again if power drops, then 
returns, then drops again.  This intentional design goal kills batteries 
pretty quickly.

Perhaps by accident, I found Cyber Power branded UPS units that 1) claim 
an 8 hour charging rate and 2) FCC Part 15 Class B compliance for their 
pseudo-sinewave units. I have two of them in my shack with a 160M 
vertical only 25 ft away, and with good chokes on their wiring, can't 
hear any noise when they're in standby mode.  Haven't checked for noise 
when they're inverting.

I use one to keep an ancient tower computer running, and the second one 
to backup the 120V accessories -- rotator controllers and SteppIR 
controller -- and the laptop PSU is plugged in there.

73, Jim K9YC

On 8/31/2017 10:46 AM, Lynn W. Taylor, WB6UUT wrote:
> Jim's suggestion also lets you size the battery to run all the gear 
> for more than a few minutes.