Assertion: phone system's line | /r/CapableOf | use yellow/black pair
Facets:
Source sentences:
text: Older houses often have 4-conductor telephone station cable in the walls color coded with Bell System colors: red, green, yellow, black as 2-pairs of 22 AWG (0.33 mm²) solid copper; "line 1" uses the red/green pair and "line 2" uses the yellow/black pair.