The setup for this experiment is the same as for Experiment 5.3,
i.e. we will mechanically connect two motors, using one as a
tachogenerator and driving the other with the motor amplifier.
However, instead of applying a square wave and measuring the
step response, we will apply a sequence of sine waves and measure
the
frequency response.
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Step 1: |
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Disconnect the function generator from the input to the motor
amplifier.
Leave the scope connected.
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Step 2: |
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Connect D/A output 1 (pin 11 on the interface board socket strip) to
.
Also connect A/D input 4 (pin 5) to
.
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Step 3: |
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Connect A/D input 5 (pin 6 on the interface board socket strip) to
.
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Step 4: |
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Reload the "Frequency Response" program.
Set the parameters as follows:
- Flo=0.2 Hz
- Fhi=100 Hz
- Nsteps=20
- Amplitude=5 V
- Magnitude Scale: dB
- Frequency Scale: Log
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Step 5: |
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Run the program.
This will take a bit longer than the other two circuits
(it takes 10 seconds to generate a single cycle of a 0.1 Hz
sine wave).
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Question 4: |
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As in Question 2, estimate
from the frequency response.
Compute
and compare it with what you measured in Experiment
5.3. Which do you think is more accurate?
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