Jeulin 223 008 Mode D'emploi page 63

Ultrasounds
Moduson table
Ref :
223 008
3.1 Step 2: Protocol
 Preliminary setting of the transmitters
1. Install the two transmitters in the magnetic recess on the moulded PVC table. Place them
2. Disconnect the transmitter 2 and observe the signal transmitted by the main transmitter
3. Switch the main transmitter ON: then the two transmitters operate simultaneously and
 Measurements:
What are the oscilloscope settings?
Select the distance a between the 2 transmitters and the radius D of the receiver
displacement arc.
Move the receiver and observe the amplitude peaks and minima of the signal sensed by the
receiver and observe on the screen of the oscilloscope.
What explanation can you give about this observation?
How to proceed to perform correct measurements?
Note: The minima are more easily identified that the peaks. However, the minima are not
zero and they are less and less marked. What explanation can you give about this finding?
ENGLISH
•
The main transmitter is assumed to be set at its maximum transmission level. It is
connected to the MODUSON transmitter 2.
•
The two transmitters connected to the same signal generator are synchronous
sources. However, the following adjustments are required to give them an identical
amplitude:
at a distance of e.g. 2 cm from each other (smallest distance). Place a receiver in one of
the arc-shaped recesses opposite the zero-degree angle value (then the receiver is
located on the median of the segment joining the two receivers and it is equidistant
between them) and connect it to the vertical input of an oscilloscope.
and sensed by the receiver. Record the amplitude value. Connect the transmitter 2 and
switch the main transmitter OFF (in this position, the transmitter member is off but the
generator is not and continues delivering the same signal on the BNC connector, hence
to the transmitter 2), then only the transmitter 2 is active. Using the transmitter
potentiometer, trim the amplitude of the received signal so that the amplitude value is
identical to the previous reading.
they have the same amplitude. This produces a peak that is sensed by the receiver (a
slight position adjustment by 1–2 degrees may be necessary to obtain this peak).
•
for vertical amplification
•
for horizontal sweep
•
D=
•
a=
:
:
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