63 lines
1.7 KiB
Org Mode
63 lines
1.7 KiB
Org Mode
|
* Measure of the noise of the Voltage Amplifier
|
||
|
|
- The two inputs (differential) of the voltage amplifier are shunted with 50Ohms
|
||
|
|
- The AC/DC option of the Voltage amplifier is on AC
|
||
|
|
- The low pass filter is set to 1hHz
|
||
|
|
|
||
|
|
Measure: Second Column
|
||
|
|
|
||
|
|
meas3: Ampli OFF
|
||
|
|
meas4: Ampli ON 20dB
|
||
|
|
meas5: Ampli ON 40dB
|
||
|
|
meas6: Ampli ON 60dB
|
||
|
|
meas7: Ampli ON 80dB
|
||
|
|
|
||
|
|
* Measure of the noise induced by the Slip-Ring
|
||
|
|
Setup:
|
||
|
|
- 0V is generated by the DAC of the Speedgoat
|
||
|
|
- Using a T, one part goes to ADC
|
||
|
|
- the other part goes to the slip-ring 2 times and then to the ADC
|
||
|
|
- Gain of the Voltage Amplifier: 80dB, AC, 1kHz
|
||
|
|
- Everything is OFF
|
||
|
|
|
||
|
|
We had some diffuculties to not have a lot of noise on the measurement.
|
||
|
|
|
||
|
|
First column: Direct measure
|
||
|
|
Second column: Slip-ring measure
|
||
|
|
|
||
|
|
Measurements:
|
||
|
|
- meas8: Slip-Ring OFF
|
||
|
|
- meas9: Slip-Ring ON
|
||
|
|
- meas10: Slip-Ring ON and omega=6rpm
|
||
|
|
- meas11: Slip-Ring ON and omega=60rpm
|
||
|
|
|
||
|
|
* Measure of the noise induced by the slip ring when using a geophone
|
||
|
|
|
||
|
|
The geophone is located at the sample location
|
||
|
|
The two Voltage amplifiers have the following settings:
|
||
|
|
- AC
|
||
|
|
- 60dB
|
||
|
|
- 1kHz
|
||
|
|
|
||
|
|
The signal from the geophone is split into two using a T-BNC.
|
||
|
|
On part goes directly to the voltage amplifier and then to the ADC.
|
||
|
|
The other part goes to the slip-ring=>voltage amplifier=>ADC.
|
||
|
|
|
||
|
|
The other two cables that go through the slip ring have 50Ohms resistors at one end, the other end is open circuit.
|
||
|
|
|
||
|
|
|
||
|
|
First column: Direct measure
|
||
|
|
Second column: Slip-ring measure
|
||
|
|
|
||
|
|
- meas12: Slip-Ring OFF
|
||
|
|
- meas13: Slip-Ring ON
|
||
|
|
|
||
|
|
* Measure of the influence of the AC/DC option on the voltage amplifiers
|
||
|
|
|
||
|
|
One geophone is located on the marble.
|
||
|
|
It's signal goes to two voltage amplifiers with a gain of 60dB.
|
||
|
|
On voltage amplifier is on the AC option, the other on the DC option.
|
||
|
|
|
||
|
|
- meas14
|
||
|
|
|
||
|
|
|