[GreenKeys] What is this test meter?

[Gary Chatters]

eBay item: 290078974344

Listed as an "impedance meter".  With labels such as "MARKING", 
"SPACING", and "LOOP", it looks to be a TTY test set.  Does it just 
measure distortion?  Guessing from the labels it looks like it might 
generate a signal also.

Anybody familiar with this one?  Looks like it could be useful, but I 
have so much stuff I am not likely to bid on it.


Gary