15.1 DVM
     DVM = Digital Volt Meter (measures volts)
     
     15.2 DMM
     DMM = Digital Multi Meter (measures volts, ohm, capacitance,
    and some measure frequency)

     15.3 TDR
     TDR = Time Domain Reflectometer (measures cable lengths, 
    locates impedance mismatches).

     15.4 Tone Generator
     Tone Generator and Inductive Amplifier = Used to trace cable pairs,
     follow cables hidden in walls or ceiling. The tone generator will
     typically put a 2 kHz audio tone on the cable under test, the 
     inductive amp detects and plays this through a built-in speaker.
     
     15.5 Wirmap Tester
     Wiremap tester: checks a cable for open or short circuits, reversed 
     pairs, crossed pairs and split pairs.

     A least-cost wiremap type tester that detects split pairs correctly
     (using a NEXT test) is the Fluke 610, at $400.  MOD-TAP and UNICOM
     make a similar device.

     15.6 Noise Tester
     Noise tests, 10Base-T: the standard sets limits for how often
     noise events can occur, and their size, in several frequency ranges.
     Various handheld cable testers are able to perform these tests.

     15.7 Butt-in
     Butt-in set: a telephone handset that when placed in series with a
     battery (such as the one in a tone generator), allows voice communication
     over a copper cable pair. Can be used for temporary phone service in a
     wiring closet.

     15.7 Fiber Testing
     See section 20.7 for fiber optic test equipment.