4/5/01: replaced CB in board 4 (slot 16) in crate A17 (GR)
        Caused readout failure in TDDAC.

        was CB109, now is CB29

4/xx/01: replaced TDC in slot 12 of TDC3 crate (GR)
         was A83486, now is A83481

         PRobably the board is OK.  We tried this as a remedy for SYNC
         errors. 

4/xx/01: replaced FERA module in crate 12, slot 10 (GR,MD)
         No data in QOD plots.

         was 84093, now is 84166

4/13/01: replaced TDC in slot 14 of TDC3 crate (Kozh?)
         PRobably the board is ok.  The board was replaced to try to
         get rid of SYNC errors.

         Was A83474, now is (not known)


4/24/01: replaced TD board 13 (crate a17, board 4).  (GR)
          Channel 2 had a problem with linearity difference.  
          Replaced with TD board 114.  Kept control board 29.


6/19/01: replaced IO board in slot 21 of trigger crate (GR)
         Was board serial number 10.  Replaced with board 8.
         This was an attempt to fix a trigger hang problem, but swapping
         the board didn't do anything, so board 10 is ok.


6/27/01: replaced SSP CPU board in slot 9 master crate (GR)
         Was board 9; replaced with board 3.
         This was an attempt to make the SSP in slot 8 visible on the crate
         segment.  It turned out the problem was on the cable segment which
         was somehow hanging the crate segment side.
         So board 9 is ok.

7/11/01: replaced TD board 5 (crate 614, board 0).  New board is 41.  
         Kept control board as before.
 
         replaced TD board 20 (crate 614, board 5). New board is 209.
         Control board retained.

7/12/01: replaced TD board 39 (crate 612, board 2). New board is 115.

7/17/01: (GR,DJ) replaced ADC1881 in ADC2 crate, slot 9.  All the channels
           reported 'no data' in FBPED.

          old S/N A83605
          new S/N B24729

7/18/01: (GR,DJ) replaced TDC1879 in TDC2 crate, slot 13.  New board A43646; 
           old board A43657.  This new board was subsequently swapped with
           the board that was in slot 12.

           All this was an attempt to cure BV TDC distribution which was
           showing low occupation and narrow widths.  This swap changed
           the symptoms, and even cured the symptoms for a while, but was 
           not satisfactory.  (Another symptom was a shift in the target
           TDC time of the prompt peak.)

           Subsequently it was discovered that the -15V on the crate was
           around -14.6 (due to a sticky switch).  Restoring the voltage by
           unsticking the switch cured all problems.  Thus the original
           TDC is probably ok.

7/24/01: (GR) replaced TDCB in crate A18, board 2.  Was giving readout
           errors during TDDAC.  Old board S/n 106; new board S/N 55.

7/26/01: (GR) replaced TDCB in crate 615, board 5. Was giving readout
           errors during TDDAC.  Also showed up as missing fiducials in
           QOD.  Old board S/N 84; new board S/N 71.

           Replaced TD board 6 in crate 612.  Channel 2 (A side) has 
           linearity problems in TDDAC.  Old S/N 14; new S/N 13.

           Replaced TD board 7 in crate 612.  Mounting block for
           front panel screws seem to be stripped so that they fall out when 
           extracting the board.  Old S/N 31; new S/N 39.

8/23/01: (GR) replaced SSP in slot A, master crate.  Suspect lower left
           front panel is flaky and leads to problems on cable segment 4.
           Old S/N 9C.  New S/N = 1.

8/25/01: (RP) replaced TDC in slot 7 of TDC3 crate.  Was intermittent with
           FRC errors every few hundred events.  Old S/N A83494.  New S/N not
           recorded.  Interestingly, board A83494 has a sticker on it saying
           'intermittent faults 6/18/98'

8/29/01: (GR) replaced TDDAC board in TD crate A18.  Channel 2 had no output.
           Old S/N 25. New S/N 11.

8/31/01: (TN,GR) replaced ADC1881 in ADC2 crate, slot 6.  Pedestals were
           very wide (80 counts, instead of typical 30).

           Old S/N A83573.  New S/N unknown.


         (GR) replaced TD control board in crate 612, board 7.  QOD
           was complaining about pmax formation for channel 1.

           Old S/N 147. New S/N 72.

9/06/01: (GR) replaced TD board in crate 601, board 1.  ch 1 failed TDDAC
           This was done between runs 43107 and 43108.

           Old S/N 205. New S/N 31.

9/09/01: (GR) replaced TD board in crate 612, board 2.  ch 3 failed TDDAC.
           Board replaced between runs 43281 and 43282

           Old S/N 115. New S/N 5.

09/16/01: (GR) replaced SSP in crate 80D (S/N 9).  Had problems at SSPinit.
            Seems to fail sspcheck on cable segment in test crate.
            Replaced with S/N 32.

09/17/01: (GR) replaced TD board in crate A17 (S/N 44).  Channel 0
            failed TDDAC.  Linearity overlap is bad.  Replaced with S/N 14
            just before run 43627.

            Also replaced TDCB in this slot.  (S/N 156 --> 67).  This
            was due to confusion caused by readout failures when the 
            RW line came loose from the TDDAC board.  The control board
            should in fact be OK.

            Found termination jumper was missing on TDCB so I inserted one.  

09/18/01: (GR) replaced TDCB (S/N 132) in TD board 7 of crate A17.  New board
            S/N 156.  This was an attempt to solve a problem with L1.1 return
            codes from this half crate, but did not have any impact.
            Thus the original TDCB is probably ok.

            Removed jumper (AXJ1-4) from TDCB (S/N 144) in TD board 0 of
            crate A17.  There could be a problem with AX.TRCL and AX.TRCH
            on this TDCB.  TD board 3 now has the jumper.

            On the left half-crate of TD07, the jumper is now in TD board 4
            instead of board 7.

09/21/01: (GR) replaced TD board (S/N 39) in board 7 of crate 612 after
            repeated TDDAC failures.  New board S/N 115.  This was before
            run 43896.


10/09/01: (GR,DJ) replaced TD board and TDCB in board 5 of crate 614.
            We're not sure whether the problem is in the TD board itself
            or in the control board.  In TDMON trigger, this board
            has no data 5% of the time. 

            S/N TD board: 209 --> 205
                TDCB      112 --> 132

            This change was made before run 44746.

10/14/01: (GR) replaced TD board 5 in crate 614.  Had some TDDAC problems
            although they would go away after several retries.  Also
            shows up in QOD (cosmic) as having many entries with low 
            pulse area, and non-prompt times.

            S/N 205 --> 209

            This change was made before run 44952.  Note that I put back
            TD board 209 that we took out on 10/9.  If this works, then
            we can conclude that the problem on 10/9 was with the TDCB.

10/16/01: (GR) AK replaced SSP in CCD D crate.  Hybrid HB-1 seemed to
             have problems on all channels.

             S/N 32 --> 21

             Tested in test crate.  Passes all tests.  Hybrid voltages
             looked ok.  Took out HB-1 an cleaned the contacts.


10/17/01: (GR) AK replaced SSP in CCD A crate.  Was not visible on cable
             segment via sspar.

             S/N 24 --> 23.

             Tested in test crate.  Initially not visible on cable segment,
             but became visible after replugging in the cables.

10/17/01: (GR) replaced TD board 6 in crate 612.   Had TDDAC problems on ch 1. 

             S/N 13 --> 49.

             This change was made before run 45066.


10/29/01: (GR) replaced SSP in CCD D crate after troubles at SSPinit

             S/N 21 --> 9

11/04/01: (GR) replaced SSP in CCD D crate after troubles at SSPinit

             S/N 9 --> 32

11/05/01: (GR) replaced TD board 3 in crate A13 after TDDAC failure in ch 2

             S/N 51 --> 39

             This happened before run 45925.


           Later found that ch 3 of the replacement board (S/N 39) started
           failing TDDAC.  Decided to swap board 3 in A13 with board 3 in
           A18 (where channel 3 is not used).

             so S/N 39 goes to A18 board 3
                S/N 45 goes to A13 board 3

           Mysteriously A18 board 3 did not fail TDDAC....

           This happened before run 45934.

1/17/02: (GR) removed SSP S/N 26 from ADC2 crate.  Had intermittent problems
           in test crate with sspcheck on cable segment.  Bit 3 missing.

           Replaced with SSP S/N 23 which was in CCDA crate.

           We've run out of SSP2's and right now we're not reading out 
            the CCD's. 

1/18/02: (GR) replaced TDC in slot 9 of TDC3 crate.  Had intermittent
            problems with readout of CSR 16.

             old S/N B28872 --> new S/N A83474

1/30/02: (GR) replaced TDC in slot 11 of TDC3 crate because it was giving
             SYNC errors.

             The board was originally in slot 10 where all the SYNC errors
             were happening.  We then swapped the boards in slots 10 and
             11 and the problem moved to slot 11.

             old S/N B22231 -> new S/N A83471

2/1/02: (GR,BB) replaced FERA module in crate 11, slot 8 because of large
             pedestal sigma on almost all channels.

             old S/N 85421 --> new S/N A97802

             This was just before run 46491.

2/3/02: (GR,AK) replaced TDC in slot 5 of TDC3 crate because of intermittent
             problems reading out CSR 16.

             old S/N B28877 --> new S/N A83499


2/4/02: (DB,AK) replaced TDC in slot 9 TDC3 crate because of SYNC errors

             old S/N A83474 --> ???

2/8/02: (GR) replaced TD control board in crate 612, board 2

             Channel 1 was having problems in psum formation.

             S/N: 104 --> 903

             TD board left unchanged.

2/12/02: (BL,SK) replace TDC in slot 5 TDC3 crate because of flakey common
		 stop time-out.

		 old S/N A83465 --> new S/N A83465

2/15/02: (GR,BB) replaced SSP I in trigger crate

                 Had problems with sspcheck in the trigger crate.
                 Tested in test crate and also had problems.  However,
                 later on, we became suspicious of the test crate, so
                 this SSP should be tested again.


                 old S/N 16R --> new S/N MWE2C

2/18/02: (GR,DP) replaced SSPII in TDC2 crate

                 Run light was stuck on.  Checked fuses and found F4
                 had resistance o ~800 ohms.

                 old S/N 7 --> new S/N 5

2/19/02: (GR,EV) replaced TDCB in slot 19 of TD crate A01.  This was
                  done just before run 47100.  Don't remember serial
                  numbers involved.

                 From the ELOG:

Several runs this morning ended due to a FB error from this slot.  The final
straw was when we could not make contact any longer with A01; the SSP in
this crate had its lights flashing.  However, putting the same SSP in the
test crate, the SSP worked just fine.  Power on the crate was fine too.  
We then removed all the TD's in A01 and found that the SSP worked ok.  From
there it was a matter of finding which TD board was the culprit.  slot 19
was the one we tried because of its troubles this morning, and it turned out
to be the guilty one after all.

2/25/02: (GR) replaced TD board 7 in crate 612.  Channel 3 failed TDDAC
               even with no input connected.

                 old S/N 115 --> new S/N 51

                This was done before run 47210.

3/07/02: (GR,BB,DJ) replaced TD board 1 in crate a01. channel 0
        had a bad connector

                 old S/N 217 -> new S/N 205

                This was done before run 47404.

3/14/02: (GR) replaced TD board 3 in crate A01.  Channel 3 repeatedly failed
               TDDAC even with no input signal.

                old S/N 37 --> new S/N 13

              This was before run 47830.

3/19/02: (GR,Kozh) replaced SSP in crate A01.  The symptoms were: 1) many 
               readout failures (of different types) on that cable segment,
               2) SR light flashing on the SSP, 3) the ssp failed sspcheck.

               old S/N 18 --> new S/N 7

3/25/02: (GR) replaced SSP in crate A01.  Symptoms were: 1) timed out in
               SSPinit at INIT, 2) could not see anything in crate A01
               even with CS terminated right there.

               old S/N 7 --> new S/N 25

3/27/02: (GR,DJ) replaced TD controller board for slot2(from 0) of TD06
              this board contains TD channel 201 which had a 1% failure
              rate in TDMON triggers and a possible problem with intermittently
              going into 'debug' mode.

              old S/N 134 --> new S/N 112
              this change done before run 48427

3/27/02: (GR) replaced ADC2 slot 10.  Pedestal value low (200 instead of 500);
              also some channels were getting significantly less than 
              1000 events in ped runs.

              old S/N A83598 --> new S/N B24743

              This was before run 48425.

3/30/02: (GR) replaced TD control board in crate 614 slot 5.  Channel 0
              was not asserting Formbank DONE.

              old S/N 132 --> new S/N 15

              This was before run 48561.

4/3/02:  (GR) replaced TD board in crate 614 slot 1.  Channel 2 had
              TDDAC problems even with no input.  Looks like a DC offset
              on both FADC channels of channel 2.

              old S/N 29 --> new S/N 37

              This was before run 48656.

4/11/02: (GR) replaced TD board in crate 614 slot 1.  Channel 3 had
              TDDAC problems.  Looks like linearity is not balanced
              between the two FADC's.

              This board seems to have a history of problems with ch 3.

              old S/N 37 --> new S/N 217

              This was before run 48777.

4/12/02: (GR) replaced TD control board for board 5 in crate A01.
              Channel 2 had problems with the new TDDAC.  No pulse
              was found by tdpunp in this channel.

              old S/N 42 --> new S/N 130

              This was before run 48783.

4/17/02: (GR) replaced TD control board for board 5 in crate A01.
              Had a problem at SSPinit writing to CSR C0.

              This was after power had to be turned off due to cooling problems
              upstairs.

              old S/N 130 --> new S/N 108

              This was before run 48805.

5/3/02: (DP,TY) replaced SSP in TD crate A13
              Had a long history of intermittent readout errors.  Finally
              began failing repeatedly at INIT.

              old S/N 15 --> new S/N 18

5/4/02: (SK) replaced TD control board 5 in crate 614.  Had readout error
             in channel 0 during TDDAC.

             old S/N 15 --> new S/N ??

5/8/02: (DJ) replaced 2 RS discriminators in 
	     R6, C1, slot17 old s/n A50951 --> new s/n A75522
        and  R7,C1,slot11           83999               84041

5/8/02: (GR) replaced SSP in crate A18.  Pin on front panel or AD31
             is broken.

             old S/N 24 --> new S/N 7?

             This was done before run 49380.

5/14/02: (a whole bunch of characters) replaced CAMAC crate controller 19.
             No Q response when doing CAMAC init.

             Originally replaced with controller from BV CAMAC crate. 
             Didn't work; no lights come on when powered up.

             Next tried a controller from top crate in R7 and that worked.

             This was done before run 49545.

5/15/02: (GR) replaced SSP in TDC1.  Had problem with hybrid voltage on WT 
             but did not change when I changed the hybrid.

             old S/N 27 --> new S/N 24

             This was before run 49589.

5/24/02: (GR) replaced Ancillary Logic module in FERA master crate, slot 18.
              Hybrid problem.

              This was before run 49881.

5/29/02: (DJ) replaced 1 RS discriminator in Rack 6, crate 1, slot 7
             to fix problem with channel 14 (Sector 2, Layer 9 upstream).
             old S/N 83636
             new S/N B02138
               
             This was done before run 49989.

6/01/02: (GR,SC) replaced ADC in slot 7 of ADC2 crate.  Gave no data during
             FBPED.

             old S/N: A83643
             new S/N: B24689

             This was before run 50046.

6/03/02: (GR,SC) replaced ADC in slot 9 of ADC2 crate.  Suspected ADC problem
             was causing efficiency loss.  However, there was no change
             after the board change, so the original board is ok.

             old S/N: B24729
             new S/N: A83563

             The change was made before run 50073.

6/03/02: (GR,TS) replaced CAMAC TDC (L17-C4-slot 15)

             Was module 19 in RSTDC space, but was calling itself module 17
             (sometimes 18) in our data. 

             old S/N: B37448
             new S/N: B48245

             The change was made before run 50078.

8/19/04: (GR) replaced ADC in slot 16 (dec) of ADC2 crate.  Had SYNC errors
              on first event.

              old S/N: A83600
              new S/N: unknown

              The change was made before run 50255.