
1) Phone channel 2) Phone-system connection 3) Private link 4) Private telephone channel 5) Surveying aid
Found on
https://www.crosswordclues.com/clue/tieline

Tieline Technology has offices in Indianapolis in the USA (Tieline America LLC) and in Perth, Western Australia (Tieline Pty Ltd). The company has a wide and established distribution network throughout Europe, the Americas and Australasia. Tieline develops a range of broadcast audio codecs that are sold to television and radio networks around the ...
Found on
http://en.wikipedia.org/wiki/Tieline
No exact match found.