* was later replaced by modifed module 20220170200653...
LMT4 Z+6 20220170200755 E5 high noise chip, not marked as LGS by KEK
LMT12 Z+2 20220170200748 slight offset slope towards E13. NO to 3E-4
LMT14 z-1 20220330200646 link0 has the worst OPE blip. For a few events, it has full occupancy on chips on link0 side.
LMT19 Z+5 20220330200631 chip E13 DTN peak at t=140, factor of 3.
LMT20 Z+3 20220170200614 also DTN peak at t=140, factor of 3.
LMT23 Z-6 20220170200474 VCSELV set to 4.3V.
LMT25 Z-6 20220170200422 nasty time structure in E13 in DoubleTriggerNoiseTest, which does not look like events. Not fixed by
- turning off all neighbours
- running in select 1
- turning off pin (in select 1)
- decreasing VCSEL V on DL.
- changing LV card A check was made of the integrity of this module's shunt shield. When connected to the dogleg, the connection is of order 1 ohm, but when this connection is removed, the resistance is infinite (>400Mohm). Therefore the shunt shield is not shorted to the cooling pipe.
LMT28 z-1 20220170200349 chip S1 fails the Nmask test - certain strip addresses are not formed correctly, leading to a shifted block of data wrt the usual triangular histogram contents. This chip also causes data errors in the SD test: 8 channels had to masked off to cure this problem, including the 2 channels highlighted by the NMask test.
* Was later replaced by 20220170200752...
LMT28 Z+2 20220170200357 had to reduce vvcsel to 3.0V.
LMT29 Z+1 20220330200553 link 0 DEAD. Light output of link 0 is -36 in clk/2 mode, -36 dbm when configured. Working link 1 has -4 dbM in clk/2 mode, -36 dbm when configured. Seems fibre is OK (sees LED light) but vcsel is not being driven into lasing region. Reading 11/12 chips through one link, the module basically works, however the NO test aborts at ~0fC due to BC errors. Probing LED/LEDB on the (connected) module header, 108ohms is seen - hence the connection through to the VDC chip is good. This is probably another ESD death.I would suggest that we should replace this module with a modified module, to fix two problems at once.
* Was later replaced by modified module 20220170200113...
LMT32 Z-4, 20220170200256 was consistently 2.8 C hotter than its neighbours
LMT34 Z-3 20220330200467 chip S11 2000 ENC in 3PG. Was 1780 in reception test. Cal factor?
LMT34 Z-6 20220330200545 required channels 22,23 masked off to avoid errors in SD test
LMT35 Z-6 20220170200941 modified module - flaky TX
LMT38 Z-6. 20220170200136 No pin current. Passes diode test. Needs to be run in select 1. Possible problems:
- Power supply channel
- Backplane
- Cable
- Connection at TPP
- Optical speck of dirt
- Broken/breaking fibre
- Unknown failure mode of PIN.
* In fact this module has good ipin in the pit...
LMT38 Z-4 20220170200144 link1 fails FBT at bin 7 - Chip S12 does not produce trailer properly as END.
LMT40 Z-5 offset slope S12-E13
- Not improved by running this module in select 1 - which anyway causes problem with Z-4 (see below).
- A little better with LMT40 z-6 in select 1. Better again with z-6 turned off.
- PWP 11/08/2009 - The module scheduled for this location was 20220170200098, but it now seems to be 20220170200793. I have not been able to verify if the module was changed, in which case the problems mentioned here may refer to the original module, or not...
LMT40 20220170200103 Z-4 chip S2 responds to commands meant for redundant TTC (@ Z-5)
See also Barrel4ColdTest
MissingLinks: a complete list of known dead data links and the locations of modified modules for all barrels is available here.