Difference between revisions of "Noise studies"
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− | After connecting the | + | After connecting the HV ground to the preamp end of the cable shielding |
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|width="400pt"|[[Image:outside_cage_pre_ground_to_shield.jpg|thumb|none|400px|Noise - cable shield connected to preamp ground, 1950V, 90/10 premix]] | |width="400pt"|[[Image:outside_cage_pre_ground_to_shield.jpg|thumb|none|400px|Noise - cable shield connected to preamp ground, 1950V, 90/10 premix]] | ||
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− | HV off ( | + | HV off (HV ground & cable shielding connected) |
{| border="1" cellpadding="2" | {| border="1" cellpadding="2" | ||
|width="400pt"|[[Image:ch16_0kV.jpg|thumb|none|400px|Noise, 0V, 90/10 premix, 20mV/div, 20μs/div]] | |width="400pt"|[[Image:ch16_0kV.jpg|thumb|none|400px|Noise, 0V, 90/10 premix, 20mV/div, 20μs/div]] | ||
|width="400pt"|[[Image:ch16_0kV_4MHz.jpg|thumb|none|400px|Noise - zoom on 4MHz, 0V, 90/10 premix, 20mV/div, 2μs/div]] | |width="400pt"|[[Image:ch16_0kV_4MHz.jpg|thumb|none|400px|Noise - zoom on 4MHz, 0V, 90/10 premix, 20mV/div, 2μs/div]] | ||
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Revision as of 15:11, 30 July 2010
Noise studies - scope traces for ch16, which shows the largest amount of 4MHz pickup. The left hand side plots also show some cosmics.
After connecting the HV ground to the preamp end of the cable shielding
The traces below also show ch16 at a much smaller timescale, 20 μs/div, with the HV supply to the CDC prototype on and off.
HV on (preamp ground & cable shielding connected) The envelope oscillates at about 27kHz.
HV off (HV ground & cable shielding connected)