<!-- Title: 07:19:41  Tue Feb 20 2001 -->
<!-- Crewchief: Silicon -->
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e130 - SVX BH 1 W3 - b0fib00 Slot 13 Chan 5-9<BR> 
<B> From SiDet:  occasional RO problems</B>


<!-- Date: Tue May 15 07:44:18 2001 -->
<pre>LIB and WIB tests ok, but OFTM channel 6 does not init (reads  
back 000), currents change and RO ok. 
Plugged. 
This wedge has the big ground strap hanging out. 
Connected to SB0W3 ground. 
RTVed and LOTOed.</pre>
<!-- Author: Petra -->


<!-- Date: Wed May 30 00:15:27 2001 -->
<pre>Retesting for closing: 
 
Previously reported: 
	L1 reads back zeros on init but reads data out fine. 
	Still there. This is a known FTM problem. 
 
	Otherwise seems fine. 
 
</pre>
<!-- Author: Lester -->


<!-- Date: Mon Jun 4 09:54:56 2001 -->
<h1>FTM investigation</h1> 
Non-initialization readback of Chan 6 FTM 155 565895 understood 
as disconnected jumper wire on FTM.  However, we replaced the 
FTM several times (162/565879, 161/565877, 152/566672, 
110/564034, 164/566697) and found always trouble on some 
combination of HDIs 2,3,4.  Measured light levels: 
<table> 
<tr> <th> Chan </th> <th> OBDV </th> <th> 0 </th> <th> 1 </th> <th> 2 </th> <th> 3 </th> <th> 4 </th> <th> 5 </th> <th> 6 </th> <th> 7 </th> </tr> 
<tr> <td> SB1W3-2 </td> <td> 480 </td>657</td> <td>670</td> <td>385</td> <td>570</td> <td>500</td> <td>570</td> <td>660</td> <td>350</td>  </tr> 
<tr> <td> SB1W3-3 </td> <td> 776 </td>700</td> <td>720</td> <td>705</td> <td>508</td> <td>720</td> <td>720</td> <td>416</td> <td>500</td>  </tr> 
<tr> <td> SB1W3-4 </td> <td> 600 </td>590</td> <td>720</td> <td>520</td> <td>500</td> <td>580</td> <td>750</td> <td>540</td> <td>640</td>  </tr> 
</table> 
 
and played around with Channel Swapping, with FTM 152: 
<table> 
<tr> <th>  </th> <th>5</th> <th>6</th> <th>7</th> <th>8</th> <th>9</th>  </tr> 
<tr> <th>0</th> <th>OK</th> <th>-</th> <th>BAD</th> <th>OK</th> <th>-</th>  </tr> 
<tr> <th>1</th> <th>-</th> <th>OK</th> <th>BAD</th> <th>OK</th> <th>-</th>  </tr> 
<tr> <th>2</th> <th>OK</th> <th>-</th> <th>BAD</th> <th>-</th> <th>-</th>  </tr> 
<tr> <th>3</th> <th>-</th> <th>OK</th> <th>-</th> <th>BAD</th> <th>BAD</th>  </tr> 
<tr> <th>4</th> <th>-</th> <th>OK</th> <th>-</th> <th>-</th> <th>BAD</th>  </tr> 
</table> 
 
Then noticed that "BAD" typically meant some sort of "OBDV problem", such as getting only Data Bytes, no Channel Bytes, 
but only in a particular Chip (like Chip 4).  In fact, on  
sparsification we had no readout errors.  Determined that 
this wedge needs more careful investigation, but ran out 
of time during the access.  Given that many FTMs fail in this spot, suspect problem may lie elsewhere (FIB, or slot itself).
<!-- Author: SCN -->
<!-- Comment: Mon Jun  4 09;58;42 comment by...SCN -->
Light Levels (HTML error):
<table>
<tr> <th> Chan </th> <th> OBDV </th> <th> 0 </th> <th> 1 </th> <th> 2 </th> <th> 3 </th> <th> 4 </th> <th> 5 </th> <th> 6 </th> <th> 7 </th> </tr>
<tr> <td> SB1W3-2 </td> <td>480</td> <td>657</td> <td>670</td> <td>385</td> <td>570</td> <td>500</td> <td>570</td> <td>660</td> <td>350</td>  </tr>
<tr> <td> SB1W3-3 </td> <td>776</td> <td>700</td> <td>720</td> <td>705</td> <td>508</td> <td>720</td> <td>720</td> <td>416</td> <td>500</td>  </tr>
<tr> <td> SB1W3-4 </td> <td>600</td> <td>590</td> <td>720</td> <td>520</td> <td>500</td> <td>580</td> <td>750</td> <td>540</td> <td>640</td>  </tr>
</table>



<!-- Date: Mon Oct 29 20:44:41 2001 -->
<pre>Layer-2 bit 0 stuck low</pre>
<!-- Author: Lester,Sinead, Saverio -->


<!-- Date: Fri Nov 2 18:43:40 2001 -->
<pre>L0 looks unbiased off-line. There is no current reading. 
run 127848 (9/28/2001) store 727</pre>
<!-- Author: saverio -->


<!-- Date: Mon Jan 21 22:05:57 2002 -->
Summary for L0 bias problem 
<ol> one of the original set - April 2 
<li> - has ground braid 
<li> - called the devil's wedge on Jun12, 2001, L2,3,4 truned off 
<li> Jun 23, L0 is still in the run 
<li> Jul 2, 2001 - wierd power supply state with high DVDD currents reported. 
<li> Jul 10 plots - L0 apparently OK 
<li> Jul 28, still in the base set 
<li> Jul 31, external trip but nothing on full status page 
<li> Aug 16 - was in calibration run DPS on: run 123977  
         DPS off: run 123979  
<li> sep 17 - still in cratematch set and apparently biased 
<li> Sep 20 - visual inspection of bias cable - I assume for L2,3,4, Nothing bad seen 
<li> Oct 14, DOIM tweaked 
<li> Oct 17, OK in HST summary 
<li> Oct 19 - not listed as having any problems 
</ol> 
To be continued 
 
  
<!-- Author: Jean -->


<!-- Date: Thu Jan 24 16:26:29 2002 -->
more logbook summary for L0<br> 
<ol> 
 
<li> Oct 31, 2001 - no power problems in HST map of world 
<li> Nov  7, 2001 -  
<a href= 
'/cgi/elog/det-system-elog.pl?nb=silicon&action=view&page=74&frame=2&anchor=17:52:07'> 
Noted as looking unbiased in offline monitoring  </a>  
<li> Nov. 13, 2001 charge injection, gain, BW runs 
<li> Dec 5, 2001 - considered as guineau pig ladder??? 
<li> Dec 11, 2001 comment = Error of SB1W3L0 started since run 134449  
</ol> 
Summary - I can't fine anywhere that this ladder had it's cables checked for shorts, etc.
<!-- Author: Jean -->


<!-- Date: Tue Feb 5 17:28:50 2002 -->
<pre>MEasuremnts at the connectors at the CAEN PS backside in order to  
understand the unbiasibility of SB1W3L0. 
BLACK	RED	Resistance 
VBPL0	VBNL0	infinity 
VBPL1	VBNL1	.290 MOhm 
VBPL2	VBNL2	.260 MOhm 
 
This implies that: 
1-	the tecnique is reliable. 
2-	There is a problem in the bias line between the P.S. and  
	the ladder. 
 
Next Action: 
 
Visual inspection of the JC. 
 
Umpluggin JC to verify continuity of cable from PS to JC itself. 
 
If such continuity is verified check the pins of the long  
connector between JCs. 
 
IF OK GIVE UP on this device.</pre>
<!-- Author: Gino -->