EN 61237-4:1997

Foreword
1 General
  1.1 Scope and object
  1.2 Normative references
  1.3 Definitions
2 Manual and automatic measurements
3 Procedure of measurement
4 Environmental conditions
5 Measurements on analogue audio baseband recording
  using bias
  5.1 Reproducing performance using calibration tape
  5.2 Overall performance using reference tape
6 Measurement on analogue audio recording using
  frequency modulation (FM audio)
  6.1 Reproducing performance using calibration tape
  6.2 Overall performance using reference tape
7 Special measurements
  7.1 Measurements on FM carrier (unmodulated carrier
      and deviation)
  7.2 Measurements on AGC (amplitude characteristic;
      attack time; hold time)
  7.3 Measurements on switchable noise reduction circuits
  7.4 Measurements on non-switchable noise reduction
      systems (in combination with a non-switchable AGC)
  7.5 Polarity test
Annex A (informative) Method of measurement for magnetic
         tape flux
Annex B (informative) Bibliography
Annex ZA (normative) Normative references to international
         publications with their corresponding European
         publications

Describes methods of measurement and special test signals for the analogue audio part of equipment mainly dedicated to recording reproduction of TV signals on mangetic tape on reels or in cassettes. Is applicable to acceptance tests, performance comparison and, as far as possible, to routine checks.