Here in Silicon Valley, it&#x27;s used by smart meters. All the short duration blips in the waterfall are gas and electricity meters.<p><a href="http:&#x2F;&#x2F;www.w6rz.net&#x2F;gqrx915.png" rel="nofollow">http:&#x2F;&#x2F;www.w6rz.net&#x2F;gqrx915.png</a>