Functional testing of tape recorders - involves simultaneous recording and replay of test signal and evaluation of several test frequencies

摘要

A functional testing system is esp. for response and frequency characteristics of tape recorders. A given number of measuring frequencies is taken from the tape during playback and evaluated simultaneously, recorded simultaneously on the tape and then simultaneously played back and evaluated. For additional measurement of non-linear distortions, a medium frequency is recorded and evaluated, whilst the remaining frequencies are e.g. about 20 dB below a reference frequency. Pref. only one switch is used to change from "normal" (including replay and record) to "test", and the various test operations may be part of an automatic testing programme.