ELOG AIDA

AIDA GELINA BRIKEN nToF CRIB ISOLDE CIRCE nTOFCapture DESPEC DTAS EDI_PSA 179Ta CARME StellarModelling DCF K40

AIDA

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Wed Feb 18 05:49:29 2015

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18/02/15
1300: Error seen when trying to check ASIC settings. See Attachment #1. Power cycle removed error.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; nnaida3 still performing much better than other three cards connected to detector (nnaida1,6,8). Why?
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Noticed nnaida3 was connected to only adapter PCB which did not feature a metal shielding plate on the front?
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Noise in other cards caused by possible short or capacitance between PCB pins and shielding plate?
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; -&gt; Removed all shielding plates and no difference seen. Pulser peak widths all still approximately the same.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; nnaida3+6 PCB grounds connected by thin braid, as well as nnaida1+8. These were all removed. No change.
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1830: Still seeing errors when data is sent through them Merger, see attachments #2-6.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Attached heavy duty copper braiding in loop, connecting all nnaida PCBs in use. Improved FWHM of nnaida1 by factor of 2. No change in other nnaida.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Moved kapton and bias from nnaida3 to nnaida11 (same crate, next module along) and saw no appreciable difference in the spectra.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Changed voltages in PSUs for first 16 nnaida.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; +5V -&gt; +5.5V, -6V -&gt; -6.5V, +7V -&gt; +8V.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; All +5.5V rails at 5.5V, however in PSU#1 (supplying inner FEE modules) -6.5V and +8V rails show variations of +- ~12mV and +- ~4mV respectively, between outlets.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Installed PSUs with updated voltages.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; nnaida8 FWHM improved by factor of 2 but no difference in other nnaida.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Current configuration nnaida1,6,8,11. nnaida1+8 connected to p+n side, nnaida6+11 connected to n+n side.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Current FWHM: nnaida1 ~500ch, nnaida6 ~1500ch, nnaida8 ~600ch, nnaida11 ~120ch.
&nbsp;Update response from Patrick:-
Please see posting number 39 for ideas to improve noise and possible reasons why some FEE64 are quieter than others.
I think the SYNC problem is likely due to the version of VHDL perhaps not including the flush of buffers and with the widely different data rates. 224k against 3k.&nbsp;
This should improve with the VHDL update as I think the flush system is more efficient.
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