Talk:Loop around

Article is very unclear, please revise
The article is very vague or doesn't make sense in the explanation. Who calls line A and who calls line B? Which line is the one being tested and which one is the remote line? The caller receives a test tone from who? Based on the very limited information I've been able to find elsewhere is that a technician actually plays a test tone from a device, they don't "receive" a tone. Unfortunately that is pretty much all I was able to find. Please revise the article to explain this unambiguously without assuming prior knowledge. --Wykypydya (talk) 06:25, 6 February 2011 (UTC)