[BC] UPS Causing Noise On AM Radio

[Tom Dimeo]

I am looking for a new UPS for my home computer and some 
audio gear and was considering an OPTI-UPS that is available 
for around a hundred and seventy-four dollars from Amazon.  
It is the least expensive one I found that provides a sine 
wave output.

Does anyone have any experience with this unit?  If so, in 
particular, does it cause noise on the AM broadcast band?

For about the last five or six years I have been using a 
Tripp Lite and every so often it causes an awful racket on 
the AM radio.  It lasts for several seconds then does it 
again after a few minutes then it is quiet for quite a while. 
 I guess it has something to do with the recharging circuitry 
or some testing mode it goes through.

Thanks,

Tom