D0 Calorimeter Electronics Upgrade Meeting Minutes

August 6, 1999

Meeting time is 10:30 am, Fridays in DAB1. Video connection available.
Contact Leslie Groer groer@fnal.gov.

= ACTION ITEM

Solenoid Tests

PL heard from Pat Healey that closing the platforms prior to the iron closing was going to start Sat morning.  Discussion with Delmar after the meeting confirmed that they will wait until Monday morning.
GU and Kyle will close up preamp boxes.  MG and SF will work on either closing up the cable conduit covers or clear them out of the detector and put them in a safe place.
DH will work on getting the rest of the pieces for the fan measurements in place before the closing. (ed. note: all the pieces were received on Friday and installed - new fan, fan photodetector sensors and the cover for the one PS box).
There was still a question about whether the platforms could stay in place when they close the iron.  An attempt will be made to close up with the platforms in place.  The concern is the "Blazey" boxes stick out too far.  Andy Stefanski, who did the original drawings, believes things can stay in place.
DH has got the 1553 working and reading out the various voltages, currents and sensors.  He is building a module to readout the photosensors.  The 1553 is read out by DH's PC and the PC in the Columbia office into an Excel spreadsheet.  The data can be stored on CD-R's.
A 3-D hall probe, that MG has been testing, will go in the platform so is less urgent.  MG has measured about 5mV/gauss.  We might need some amplification to see the levels of below 100 gauss that are expected at the platform level.
BM recalled that Lars Rasmussen did have standalone code in the old DAQ that monitored the various pieces   We may want to try and revive this, if possible.
 

GU and Kyle have been checking the preamp box input cables for damage,  They have checked the whole West side (CC and ECN) and the only damage was in Box 2L, left side to the colored-twisted pair that goes from the preamp output to the BLS rack.  CCE is also fine and they only have box 11 on ECN-NE to check.
LG asked about the remaining length after running the 100ft ICD pulser cables.  GU estimates that at most there was 18ft at the winder end on the East side.  There is a concern now that the original plan to pull the yellow cables from the ECS for the ICD might not work as they could be too short.  This issue should be taken up with the ICD folks.

Preamp production

MT reported that the 6 preproduction motherboards should be here next week.  These are with a red solder mask.
PL has been working on LB's boards - placed order with Pentaplex in Elgin.  They have started working on these.  Should be 10 day turnaround.  He needs to ship the Gerber files.
While LB was away this week, LG has been trying to get hold of Charlie Leung at UTY, Vista, California, with no success.  No purchase order or any other info has been received this week.
SF has been working on labels - we think we have a final size that can be read and will not cover up too much information.

PL reported that Bob Jones can work on the monitor boards - we need to get in his queues.  We have parts for 25-30.  These are almost done.
DH is reworking the PS board - there may be space on the board for a 3-D hall probe - he will have to check.
DH will get another preamp PS done.  The shields are being tin-platted.
BLS power supplies need reworking.

No word yet on the 4" packaging - should be here next week.

D. Elvira sent mail on progress:

- Included demultiplexers to replace gates in the logic to produce transition errors
- Implemented logic to check consistency of L2 SCA states when the start dig command is received (this command doesn't cause any transition but we have to make sure the SCA cell is in the right state).
- Design timers for timeout of the L2 SCA analog signal.
 

LG showed some results from tests that Zarah Casilum ran pulsing a single channel with the old preamp systems.
LG showed results for the new preamp coherence noise tests that he ran.  Ten thousand events were taken with the yellow pulsers connected and disconnected.  These clearly show that coherent noise is coming in on these pulser cables.  It is not clear, due to the new pulsing system and new BLS's, whether these effects will be present or are of concern for the final new system.

LG had done some investigation of the preamp input cable status and sent out a note.   At the meeting BM mentioned that there are a few modules where the HV channels are shorted inside the detector where the pads got crushed (CCEM).  In 1993 there were about 13 channels that were unusable, 5 of these from cut/damaged cables.
LG will check with Dean and Zarah to confirm where damaged cables are and how and when to repair these.  The cut cables in box 10 also need to be repaired when the iron is opened.
Ed Posschweit and his crew have repaired one of the sawn through preamp-BLS cables in the winder (not sure which one).  This needs to be checked.  The other cable has not been replaced yet.

A copper grounding strap on the BLS racks needs to be modified/replaced to accomodate the new BLS backplane (central 1/3 of each rack).  There are lots of screws holding this in place, so it might be easier to do this on the bench rather than in place.
There is also a power connection copper bus to the backplane that needs to be removed and reworked.  Ed Arko is aware of this, but no time has been scheduled yet.  Viktor and Don could do this work possibly?
While the iron is closed, work can be done on the platform.  This will be discussed at future meetings.