Difference between revisions of "CDC old & new preamp noise scope trace study"

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* Naomi's preAmp  : the new preAmp.
 
* Naomi's preAmp  : the new preAmp.
  
<b> Left is always Yves' old preAmp, middle is Beni's old preAmp, right is Naomi's new preAmp </b>
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<b> Left is always Yves' old preAmp, middle is Beni's old preAmp, right is Naomi's new preAmp </b>  
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[except mentioned differently]
  
 
First 2000V was put on the chamber and a random cosmic ray signal was selected:  
 
First 2000V was put on the chamber and a random cosmic ray signal was selected:  

Revision as of 15:20, 30 June 2010

A study was performed using three preAmps:

  • Yves' old preAmp : the old preamp that changed behavior a month ago
  • Beni's old preAmp: the old preamp used before by Beni.
  • Naomi's preAmp  : the new preAmp.

Left is always Yves' old preAmp, middle is Beni's old preAmp, right is Naomi's new preAmp [except mentioned differently]

First 2000V was put on the chamber and a random cosmic ray signal was selected:

Yves' old preamp - 2000V - cosmic ray
Beni's old preamp - 2000V - cosmic ray
Naomi's new preamp - 2000V - cosmic ray


OK, so far so good. Let's switch the HV off and look at the ringing: the highest amplitude ringing was selected, so you are looking at the high end of the pedestal:

Channel 1

Yves' old preamp - ch1 - ringing
Beni's old preamp - ch1 - ringing
Naomi's new preamp - ch1 - ringing

Channel 8

Yves' old preamp - ch8 - ringing
Beni's old preamp - ch8 - ringing
Naomi's new preamp - ch8 - ringing

Channel 9

Yves' old preamp - ch9 - ringing
Beni's old preamp - ch9 - ringing
Naomi's new preamp - ch9 - ringing

Channel 15 <- This channel is always used for Fe-55 measurements

Yves' old preamp - ch15 - ringing
Beni's old preamp - ch15 - ringing
Naomi's new preamp - ch15 - ringing

The old preAmp has higher amplitude noise in chip2 -> channels 9-16 The new preamp has lower amplitude ringing compared to the old preAmp.


Now it comes: remember the wierd noise peaks: