83 lines
2.4 KiB
Org Mode
83 lines
2.4 KiB
Org Mode
* DONE Measure of the noise of the Voltage Amplifier
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CLOSED: [2019-05-06 lun. 09:00]
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- The two inputs (differential) of the voltage amplifier are shunted with 50Ohms
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- The AC/DC option of the Voltage amplifier is on AC
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- The low pass filter is set to 1hHz
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Measure: Second Column
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meas3: Ampli OFF
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meas4: Ampli ON 20dB
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meas5: Ampli ON 40dB
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meas6: Ampli ON 60dB
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meas7: Ampli ON 80dB
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* DONE Measure of the noise induced by the Slip-Ring
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CLOSED: [2019-05-06 lun. 09:28]
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Setup:
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- 0V is generated by the DAC of the Speedgoat
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- Using a T, one part goes to ADC
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- the other part goes to the slip-ring 2 times and then to the ADC
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- Gain of the Voltage Amplifier: 80dB, AC, 1kHz
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- Everything is OFF
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We had some diffuculties to not have a lot of noise on the measurement.
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First column: Direct measure
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Second column: Slip-ring measure
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Measurements:
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- meas8: Slip-Ring OFF
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- meas9: Slip-Ring ON
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- meas10: Slip-Ring ON and omega=6rpm
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- meas11: Slip-Ring ON and omega=60rpm
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* DONE Measure of the noise induced by the slip ring when using a geophone
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CLOSED: [2019-05-06 lun. 09:28]
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The geophone is located at the sample location
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The two Voltage amplifiers have the following settings:
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- AC
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- 60dB
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- 1kHz
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The signal from the geophone is split into two using a T-BNC.
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On part goes directly to the voltage amplifier and then to the ADC.
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The other part goes to the slip-ring=>voltage amplifier=>ADC.
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The other two cables that go through the slip ring have 50Ohms resistors at one end, the other end is open circuit.
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First column: Direct measure
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Second column: Slip-ring measure
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- meas12: Slip-Ring OFF
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- meas13: Slip-Ring ON
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Redone the measurements with 1kHz additional low pass filter:
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- meas16: Slip-Ring OFF
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- meas17: Slip-Ring ON
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* DONE Measure of the influence of the AC/DC option on the voltage amplifiers
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CLOSED: [2019-05-06 lun. 09:28]
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One geophone is located on the marble.
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It's signal goes to two voltage amplifiers with a gain of 60dB.
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On voltage amplifier is on the AC option, the other on the DC option.
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First column: AC
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Second column: DC
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- meas14: col-1 = amp1+AC. col-2 = amp2+DC.
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- meas15: col-1 = amp1+DC. col-2 = amp2+AC.
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* Measurement of the LPF
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We are measuring the signal from from Geophone with a BNC T
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On part goes to column 1 through the LPF
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The other part goes to column 2 without the LPF
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- meas18
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New measurement with C = 150nF => fc = 1kHz
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Voltage Ampli: 60dB, DC, 1kHz
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- meas19
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