Jeulin 222 044 Mode D'emploi page 16

Periodic Phenomena
Kundt's tube with analog outputs
Ref : 22204
Then, move the rod to bring the position cursor of the microphone in front of the 500 mm
marking and note down the new voltage (this procedure completes the calibration and the
customisation of a direct entry is described in the instructions manual of the Généris 5
software).
3.3 Connecting terminals of the unit
The 3 analog outputs and the power supply for the 12 V mains adaptor are located on the
rear face of the control unit. The earth terminal is common to the 3 outputs. This technical
solution helps perform acquisitions with any ExAO interface connected to a computer, or
an oscilloscope or multimeter.
Using the tube with an ExAO acquisition system gives access to the raw signal and the
envelop curve of the sound signal simultaneously (in relation to the position of the
microphone in the tube). In this case, each analog output must be connected to an input of
the ExAO system. We thus directly obtain the position of pressure nodes and antinodes.
To view the 2 signals simultaneously on the oscilloscope, connect the output corresponding
to the raw signal to channel A and the output corresponding to the envelop to channel B.
We then see a DC voltage (channel B) passing from the maximum amplitude of a sine
curve (channel A).
Microphone position
12 V power supply
Common earth
4. Use
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Caution: do not adjust the loudspeaker sound too loud so as not to saturate the signal and
ENGLISH
Power the unit with the 12 V mains adaptor (supplied) and the loudspeaker with the
signal generator (not supplied)
Adjust the desired sound frequency of the loudspeaker using the signal generator
Open or close the tube with the foam plug depending on the experiment to be
performed.
maintain a sine wave for the envelop of the sound wave.
Rear face of the control unit
15
Envelop curve
"Raw" signal
Microphone cable