"The TF 2330A Wave Analyzer provides comprehensive measurement facilities for the analysis of the performance of devices operating within the audio and ultrasonic frequency spectrum. The amplitude of each individual frequency component of a complex signal may be determined in terms of absolute voltage or relative to a fundamental datum level in decibels or in percent.

Another function of the instrument is to provide a convenient facility for determining frequency response. A beat frequency oscillator, controlled by the voltmeter tuning and in step with it, provides a variable output which, when set, remains constant over the whole frequency range. By applying this signal to the input of a circuit and monitoring the output with the tuned voltmeter section the response of the circuit can be rapidly ascertained." (Marconi, Manual TF2330A, 1970)

BRIEF SPECS

In time Marconi was the british 'answer' on the Hewlett-Packard line of instruments. The Marconi offer includes frequency counters with heterodyne mixers, vacuum tube voltmeters, signal generators and distortion bridges. The TF 2330A is one of their audio instruments. The unit shown here is in excellent shape but does not work. I'm looking for the schematics, as I only have the instruction manual.