[TriLUG] [OT] Strange Beep from Back-UPS XS 1200

[Peter Neilson]

On Wed, 22 Jan 2014 00:30:35 -0500, Brian Weaver <cmdrclueless at gmail.com>  
wrote:

> For the last few weeks I've been trying to track down a very low, almost
> inaudible "beep" at my desk. It occurs on about a 3 second interval.

> After powering off a lot of equipment, crawling around my desk, and  
> placing my
> ear to just about every piece of gear I at the desk I've isolated it to  
> the APC Back-UPS XS 1200 under my desk.

I think it wants you to replace the battery. The good folks at  
BatteriesPlus will have one that matches. Lead-acid cells seem to die  
after about three years.

The sound from such devices is very frustrating. We can locate sounds by  
using a difference in the delay of a mix of high-pitched frequencies as  
they reflect off the curled channels of the outer ear. The usual  
explanation of location, binaural hearing, is insufficient, as it does not  
explain vertical location. Sound that does not contain a mix of high  
frequencies is difficult to locate.

In the early 1980s the British phone service, which I believe was at that  
time HM's Post Office, introduced new desk phones that used a  
single-frequency beeper instead of mechanical bells. There was a news  
report or comedy on TV showing someone frantically picking up phone after  
phone of the dozen or so in a group of closely arranged desks, trying to  
find out which one was ringing.