The AM5 Classic and AM5e Classic are microprocessor-based test instruments used to make Transmission Impairment Measurements (“TIMS”) on 2- and 4-wire circuits. Models are available for IEEE Standards and CCITT Recommendations as follows: AM5 AM5 AM5eAM5eCLASSIC-120 - - - IEEE Standard 743-1984 (Bell Standard 41009) CLASSIC-200 - - - Same as AM5 Classic-120 with extended range to 200 kHz CLASSIC-120 - - - CCITT International Recommendations CLASSIC-200 - - - Same as AM5e Classic-120 with extended range to 200 kHz Both the AM5 Classic and AM5e Classic are hereafter referred to as “AM5(e) Classic”, and except where specified “AM5” or “AM5e” all information applies to both types of Classics. The AM5(e) Classic also contains a separate full-function test tone generator which produces operator-selected and automatically-stepped (sweep) tones from 20 Hz to 120 kHz (or 200 kHz) required for tests. The AM5(e) Classic provides five (5) impedance selections for RX and TX lines, separate DC hold circuits, and a built-in speaker monitor. Optional features include a Signaling Adapter with Ring Generator, “Siemens”-type Line Test Connections, Rechargeable batteries for cordless portable operation, a snap- on cover, and a rack-mounting kit for permanent installations. The 200 kHz Model of both the AM5 Classic and AM5e Classic extends the maximum frequency response measurement and generation from 120 kHz to 200 kHz.