Rohde & Schwarz UPD, Application Note

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1GA16_1L.DOC ROHDE & SCHWARZ 3
1 Introduction 1 Introduction
Audio Analyzers UPD and UPL with their large variety of functions provide practically all measurement
procedures required in audio technology. Thanks to the Universal Sequence Controllers UPD-K1 and
UPL-B10, which are available as options, the user is able to considerably expand the range of functions to
suit his particular requirements. It is possible, for instance, to add complete measurement functions - eg
measurement of ohmic resistance - and to read out, convert or reload sweep results or to add new scale
labelling (eg group delay). Another example is the analysis of sweep curves and the display of results in a
window next to the curve. As far as softkey labelling and functions are concerned, operation of the
sequence control programs is analogous to the softkey control of the UPD/UPL graphics display.
This application contains a BASIC program permitting automatic measurements of loudspeaker
parameters with the aid of the features described above. The program can be run on UPD with UPD-K1
and on UPL with UPL-B10. The application software supports the following measurements or
measurement sequences:
•
Measurement of impedance characteristic with calculation of tuning frequency, resonance frequency
and resonance impedance, DC resistance, minimum and maximum impedance, Q factor and
equivalent volume.
•
Measurement of sound characteristic with calculation of transmission range as well as measurement
of sensitivity and peak sound pressure.
•
Measurement of intermodulation products at fixed frequencies or of harmonic distortion as a function
of frequency using a variety of measurement procedures and displays
•
Measurement of phase linearity and group delay as well as
•
Various methods for checking the polarity
The software not only yields highly accurate results for the development of loudspeakers but also
supports measurements in production testing:
•
Impedance- and frequency-response curves can be referenced to a "golden unit" so that a GO/NOGO
decision can be made for each tested device.
•
Control of measurement sequences can be stored (learned) by the program so that whole sequences
can be performed by a keystroke without any further intervention being required. Thus several
measurements can be combined to a series of measurements (macro operation).
The measurements and calculations described in this Application Note are in line with DIN IEC 268,
part 5.
2 2 Preparations Preparations
2 2.1 .1 Hardware and Software Requirements Hardware and Software Requirements
The accompanying floppy disk holds BASIC program modules and one complete setup (SPEAKER.SCO),
so that the application software can be run immediately under the UPD/UPL universal sequence controller
(UPD-K1 or UPL-B10). As regards the hardware, an UPD/UPL of basic configuration will be sufficient. An
external keyboard is required for operating the automatic sequence controller.
The following software requirements must be met:
•
UPD software version 3.03 or higher, UPL software version 1.01 or higher,
•
Universal Sequence Controller UPD-K1 or UPL-B10,
•
configuration 3 (64-Kbyte program and 32-Kbyte data memory), for very long sweeps (more than 400
sampling points) or combined near/far-field measurements possibly configuration 5 (64-Kbyte data
memory).
Note : UPD and UPL are configured with the aid of service programs UPDSET and UPLSET,
respectively.