01:39 : Attachment 26 (R30_70to72) shows a gradual change in the hit pattern for DSSD2 (at the lower left
corner) which may indicate the noise level was increasing.

02.23 BigRIPS data file 1066

03.05 Beam stopped due to problem with LINAC RF.
      Stopped at 1GB through R30_90.
      Bias and leakage currents ok (attachments 1+2). Temps ok (attachment 3).

03.15 R30 stopped.

03.22 BigRIPS data file 1067

03.24 Beam returned and R31 started.

04.25 BigRIPS data file 1068

05.29 BigRIPS data file 1069

06.26 Stop R31 in anticipation of LN2 fill.
      Run stopped at R31_56.

06.31 BigRIPS data file 1070

07.18 R32 started successfully after LN2 fill.

07.24 DAQ crashed. SYNC errors.
      R32 closed.
      Cannot soft reset. Unable to contact nnaida9+19.

07.33 BigRIPS data file 1071
      
07.49 R33 started after FEE power cycle.
      Running quite fast, but seems to be stable. F11 rate still 30cps.

08.26 /home full.
         aidas1> du -sh /home/data/
         811G	/home/data/

         aidas1> du -sh /home/data/*
         3.4M	/home/data/bkg_r97.root
         253G	/home/data/NP1306.rootfiles
         27G	/home/data/NP1512.rootfiles
         190G	/home/data/npg
         311G	/home/data/online
         2.0G	/home/data/R97_0
         2.0G	/home/data/R97_1
         2.0G	/home/data/R97_10
         2.0G	/home/data/R97_11
         1.8G	/home/data/R97_12
         2.0G	/home/data/R97_2
         2.0G	/home/data/R97_3
         2.0G	/home/data/R97_4
         2.0G	/home/data/R97_5
         2.0G	/home/data/R97_6
         2.0G	/home/data/R97_7
         2.0G	/home/data/R97_8
         2.0G	/home/data/R97_9
         7.4G	/home/data/rootFiles
         4.0K	/home/data/rsync.sh
         4.0K	/home/data/rsync.sh~
         4.0K	/home/data/ttt.txt

08.36 BigRIPS data file 1072

09.16 Beam stopped for stripper foil change.
      R33 stopped.
      GK, RG and SN will install repaired clover (G7).

09.28 Beam returned and R34 started.
      BigRIPS data file 1073

10.32 BigRIPS data file 1074

11.00 DSSSD bias & leakage currents OK - see attachments 4 & 5
      FEE64 temperatures OK - see attachment 6
      Merge statistics OK - see attachments 7-12
      System wide checks OK *except* fails for clock status (bit 2 always set) and ADC calibration - see
attachments 13-14

11.20 Visual scaler - see attachment 15

11.25 Analysis of R30_25 - see attachment 16

11.39 BigRIPS data file 1075

13.11 BigRIPS data file 1076

14.10 11.50-14.10 Spectra Rate, HitRate, 1.8.L, 1.8.H, 1.8.W - see attachments 17-24
      1.8.W spectra show some evidence of increased 100kHz noise for nnaida17, 18 & 19
      statistics good events - nnaida17, 18 & 19 > 100k data item/s - see attachment 25

14.16 BigRIPS data file 1077

14.54 BigRIPS data file 1078

15.19 BigRIPS data file 1079

16.14 BigRIPS data file 1080
16.16 BigRIPS data file 1081

17.17 BigRIPS data file 1082

18.18 BigRIPS data file 1083

19.03 BigRIPS data file 1084

18.26 DAQ stopped OK (RIBF03R1/R34_137)

      Clover HPGe LN2 refill

18.30 Beam off - for primary user calibration & stripper foil change

18.45 Ambient temperature +25.5 deg C, d.p. -5.0 deg C, RH 12.%
      DSSSD bias & leakage currents OK - see attachments 27 & 28
      FEE64 temperatures OK - see attachment 29

19.03 BigRIPS data file 1084

19.12 Statistics good events - see attachment 30
      All FEE64s < 100k data items/s, nnaida17, 18 & 19 < 50k data items/s
      Note - nothing has been changed/touched

19.40 Degraders unchanged
      (8mm Al) Fixed + ( 1mm W/1mm Al, 0.3mm W/1mm Al) variable

19.46 DAQ starts (RIBF0R1/R35)

19.50 SyncCheck OK

19.51 BRIKEN data file 155

19.53 Statistics - good events - see attachment 31
      All FEE64s < 100k data items/s, nnaida17, 18 & 19 < 50k data items/s
      Visual scalers - see attachment 32

20.00 BigRIPS data file 1085

20.08 Offline analysis R35_1 - ADc & disc data synchronised - see attachments 33 & 34

20.58 BigRIPS data file 1086

21.15 Rate, HitRate, 1.8.L, 1.8.H, 1.8.W spectra - see attachments 35-42

21.35 Found nnaida17 HEC fast comparator 0x3 *not* 0x2 
      Corrected and saved ASIC settings etc with new DB key 2016Nov29-21.38.02
      Current AIDA data file R35_22











       


      
 

 Apologies, I made a mistake in the information above.

MACB#1 is the grandparent, but #2 and #7 are the parents, with #3-6 and #8-11 the children.

The master goes through MACB#2 to the first port on #3.

So the current setup follows, and always has done, your instructions above.

24/02/15

1200: Update the FEE firmware on nnaida1-16 without problem.

           Gone from file FEE_Oct12_27Nov13.bin ----> FEE_Riken_Apr14_24.bin

           Included are a screen shot of the temperature window showing the new firmware versions and a stats screen.

12.15 Update MIDAS DAQ software

           su

           cp -r /MIDAS@aiidas /MIDAS@aidas.240214  ( /MIDAS is a link to /MIDAS@aidas )

           exit

           cd <update directory>

           cp -r Data_Acq /MIDAS

           cp -r Merger /MIDAS

           cp -r TclHttpd /MIDAS

           New versions of merge64.AD and master64 were installed in /MIDAS/Merger but the process crashed at startup

           with multiple messages of the type:

           MIDAS Data Link (12345) : Received SEGV signal; exiting.

          (see attachment 3)

          Is this related to the recent changes to the MIDAS TapeServer software to resolve problems with MIDAS Data

          libraries libdataspy.so  and libxfer.so ?

           As a temporary workaround I have copied the backups of merge64.AD and master64 back to the install

           directory /MIDAS/Merger. With the old verison of the merger we continue to obtain error messages

           (see attachments 4-8)

20/04/15

1200: Complete all points on first part of check list, except checking the PSU voltages.

          System now in powered and has all network/HDMI cables attached.

1300: Connect RPi to power switch but when powered on it didn't find the switch. A reliable procedure to start seems to be...

• connect USB power switch to RPI, make sure serial cable is disconnected from hub
• power up RPi and power switch
• check connection using dmesg, should see ...FT232RL for USB power switch on USB0
• check connection from aidas1 by pinging RPi inet address 10.1.1.251
• if good, Rly16 page should work from aidas1
• connect serial cable, open PuTTY session, select AIDA console settings, open
• should assign serial cable as USB1 an allow use of both the power switch and FEE console.

       Currently this all works, we can control the power switch both from the RPi and aidas1, and see the FEE console via PuTTY session.

1400: Powered on system and tried to set up DAQ but received error (attachment 1) when doing the initial system reset in Run Control.

          DAQ still usable for spectrum/temperature viewing, and all FEEs can be accessed to check ASIC control, but it seems timestamping will not be correct.

          Tried to perform manual ReSync from master timestamp window and received similar error (attachment 2).

1430: nnaida8 running quite hot (ASIC temp ~65^oC) and ASIC temp on nnaida7+15 read as 0.00^oC. Otherwise, from pulser/stats data, both seem to be working correctly.

          Unplugged power cable for nnaida7+8 at PSU end.

1600: Could timestamping issue originate from MACBs?

          In rebuilding AIDA MACB -> FEE cabling redone. Should it follow a particular pattern/tree?

          Current tree structure looks like (with MACB numbering going 1->11 L->R as you look at it):

                  MACB1(setting: 0) ------- out 1: MACB2 (setting: 2) ---------- out 1: MACB3 (setting: 2) -> nnaida3+4, 11+12

                                                                                                    ---------- out 2: MACB4 (setting: 3) -> nnaida19+20, 27+28

                                                                                                    ---------- out 3: MACB5 (setting: 3) -> nniada1+2, 9+10

                                                                                                    ---------- out 4: MACB6 (setting: 3) -> nnaida17+18, 25+26

                                              --------- out 2: MACB7 (setting: 3) ---------- out 1: MACB8 (setting: 3) -> nnaida21+22, 29+30

                                                                                                    ---------- out 2: MACB9 (setting: 3) -> nnaida7+8, 15+16

                                                                                                    ---------- out 3: MACB10 (setting: 3) -> nnaida5+6, 13+14   -----> nnaida5 is the master and this comes from output2.

                                                                                                    ---------- out 4: MACB11 (setting: 3) -> nnaida23+24, 31+32

          Patrick - Is this set up OK? Do certain FEEs need to receive the MACB signal from certain MACBs or just all at the same point in the tree?

                        Also, MACBs 2+3 are on setting 2 on the dial, whereas the others (except MACB1, the 'grandparent') are set to 3. It seems like a hard thing to change accidentally so are they supposed to be like this or should they all be on the same setting?

1630: Voltages to nnaida7+8 OK at PSU output (+6V, +6V, +6V, -6.5V, +8V). Issue with contact to cooling rack?

          With pulser input to all FEEs, only see pulser data in spectra for n-side (nnaida3+4, 7+8, 11+12, 15+16) FEEs. Other FEEs all show zero statistics.

It would appear that you cannot reliably startup the Raspberry Pi (nnrpi1)
connected to both the USB ac mains switch *and* the USB-serial link to FEE64
console. This is because the Rly16 Service to the USB ac mains switch expects
to use /dev/ttyUSB0. However this is often assigned (at Raspberry Pi startup)
to the USB-serial link.

You can use the command 'dmesg' to observe device assignments. 

Workaround

- connect USB cable from USB ac mains witch to powered USB hub socket 
- switch off & disconnect USB-serial cable from powered USB hub socket to FEE64 console
- power up Raspberry Pi (nnrpi1)

At startup the USB ac mains switch should be assigned to the first available
device /dev/ttyUSB0 - as required.

- connect & switch on USB-serial cable from powered USB hub socket to FEE64 console

The USB-serial connection should be assigned to the next available devoce /dev/ttyUSB1 
- as required. Further instructions can be found at:

https://elog.ph.ed.ac.uk/AIDA/42

21/04/15

1325: Recabled the MACB distribution tree as per PC-S instruction yesterday.

          Now have nnaida5+6, 13+14 in MACB3 (nnaida5 in output 1) and nnaida3+4, 11+12 in MACB10 (following the numbering system used in yesterday's ELog entry).

          Complete system now happily resyncs on initial reset after power cycle.

          nnaida7+15 still give a temperature reading of 0^oC and nnaida8 is still running hot, but stable, at 65^oC.

          Visual inspection of cooling crate didn't reveal and air gaps between cooling plates and the FEE cards, or anything else to suggest there would be lower than expected cooling performance.

1340: After complete system start up, nnaida3+4, 11+12 now show absolutely no data (empty histograms, no good events/SYNC pulses in stats). (Attachments 1-4, example good spectrum/stats attachments 5-6)

          nnaida5 shows nonsensical data in histograms. (Attachments 7-8)

1500: Swapped HDMI cables from MACB NIM mdules cabling for FEE modules nnaida1+2, 9+10 for nnaida3+4, 11+12 - problem appears to move implying MACB is the problem

          Swap MACB #13 for MACB #4 - problem resolved (still in position #10 as per CG numbering system used previously).

1600: nnaida5 does not produce sensible data - typically ~3-4 active channels with ADC and fast disc data with rates ~kHz/channel

           Swap nnaida5 & 6 for (currently not used and not powered) nnaida27 & 28. Update /etc/dhcp/dhcpd.conf, restart dhcpd.

1800: Sync problem resolved, stable operation all afternoon including several system resets - no ReSync issues noticed. SYNC pulses provided to all FEEs consistently.

          Connected detector BB18 2977-20 (same detector as used during Feb 2015 tests, with same kapton config as per 1520 on Feb 19th) to system with +ve 100V bias provided to n-side.

          Updated firmware in new nnaida5+6 (formerly nnaida27+28) to be in line with all those currently in use.

          Used saved ASIC settings from Feb 2015 visit and see similar FWHM in most spectra to those found during February after connecting heavy duty copper braids in loop between FEE modules in use.

          nnaida5 still does not produce sensible data with almost identical spectra/stats to those seen before the module was replaced.

          To be investigate tomorrow.

New Kapton PCB design (2x 0.45m + inter-connecting PCB, no ground plane layers)  under test with small system in T9.

3 cables modified to remove ground connection.

When just connected to system and BB18 2998-20, with no additional grounding or shielding of the cables

and bias of  +200V (leakage current  +6.2uA, ambient temp +27 deg C) to nnaida14, we observed average pulser peak widths

of ~250ch FWHM

Waveforms were just noise.

Added heavy duty copper braid between adapter PCBs, the small metal box for the detector and Cu tape and drain wire to the kapton connected to nnaida14.

This reduced the peak widths to ~160ch FWHM

Adding grounding between the adapter PCBs and the NIM bin chasis increased the peak widths.

Waveforms for nnaida11-13 remained unchanged, but expected (albeit noisy) traces could be seen for nnaida14).

        ------> Patrick: with ASIC1 waveforms for all nnaida turned on, we found they would occasionally stall for some. e.g. of 4 being observed, upon update, only 1 or 2 actually would. Stop-Go did not resolve this. Load/check ASIC resolved issue.

nnaida14 developed double peaking of pulser peak.

Note waveforms exhibit significantly faster risetime than previous Kapton PCB variants => lower C, as expected

Upon starting system with nothing connected beyond adapter PCBs, observed pulser peak FWHM of ~12-15ch in nnaida13+14 and ~15-18ch in nnaida11+12

All newly shielded new kapton cables passed continuity tests between drain wire and Cu tape.

Throughout all tests, grounded cable has been connected to nnaida13. All other nnaida have ground isolated cables.

Initially, upon biasing, leakage current reached 50uA at ~2V HV and tripped.

After much searching, found one of the drain wires from the kaptons to be touching the core of the HV cable.

Tidied all drain wires and made sure none were touching anything they shouldn't.

Bias ramped up successfully to +200V with leakage current of 5.630uA @ room temp ~25.5oC.

Very noisy waveforms to begin with, notes Cu tape on kaptons was in contact with the Al housing for the detector.

Isolated kaptons from Al housing with black tape and the waveforms became much less noisy, but still not as calm as expected.

Connecting Cu covered kaptons with croc clips made this problem worse. However, grounding adapter PCBs together improved the waveform noise.

FWHM with new cables ~200-300ch, much worse than previous cables.

Reconnected system with old kaptons and they now see FWHM of ~200-300ch, as opposed to ~100ch observed earlier in the year.

What has changed?

Waveforms are smoother with old kaptons, but still not as flat as previously observed.

Had some issues with waveforms not being output by FEE cards and ASIC4 of nnaida12 has failed to Check/Load and is not outputting any data.

Standard ASIC parameters throughout, with shaping time of 0.5us.

This morning PC-S changed firmware and DAQ software to that of the RIKEN setup

Firmware version /MIDAS/AIDA/FEE_Riken_Apr14_26.bin

DAQ software has been changed from AidaExecV8 to AidaExecV7

nnaida12 is not playing ball -> ASIC4 has stopped outputting any data and ASICs2+3 are missing multiple channels. Not running hot

Suspicions over the power cable as the source of the problem (previous nnaida12 developed noisy ASICs) and tests found this not to be an issue. Neither are the MACB HDMIs as they were swapped for new ones last night.

Then changed the adapted PCB to see if that was a possible cause. No change -> FEE or mezzanine problem?

With old kaptons attached, peak widths in nnaida11 are ~180-190ch with shaping time 2us. Increasing this to 6us brings FWHM to ~170ch, and increasing further to 8us reduces the FWHM to ~140ch.

FAO PC-S -> After lunch, upon clearing the spectra, nnaida12 stopped responding (terminal screenshot below - attachment 19). Brought system to halt. Power cycling resolved the isssue.

A series of tests over the afternoon found peak widths to vary only by ~10-20% when the second length (detector end) of kapton was removed. Removing the connecter PCB showed no improvement over this.

However, removing the Cu tape put on as shielding, reduces the FWHM by a factor of 3.

see nnaida11_wav_newCable.png (attachment 17) for before waveforms -> the Cu tape is clearly doing something we are unaware of.

Attachment 18 shows improvement in just removing the Cu tape.

Re-adding connector PCB, increased widths by ~5-10% and re-adding second length of kapton increased widths by x3-4.

Second length of kapton was tested on its own and was found to have roughly the same widths as the first length, no issues with this cable -> increase in FWHM just due to increased capacitance (possibly...)

Connected a 45cm kapton to each FEE, 3 with the ground connection broken, and the grounded one connected to nnaida13 (attachment 23).

Varied shaping time and found 0.5us to consistently provide lowest FWHM (summary graphs to follow).

With just one length (+connector PCB) of kapton connected to adapter PCBs, waveforms all look very good, too good to explain the higher than expected FWHM.

Upon connecting 90cm of kaptons, noise creeps in to waveforms. Also observed reoccurring periodic transients in some waveforms (attachment 20).

Rise time with new kaptons connected (45cm) noticeably faster that with the old cables -> new show rise time of ~140ns, old cables has rise time ~3us.

To do tomorrow:

connect detector to FEEs using 4 45cm kaptons, assess affect on FWHM.

Powered system up with 4 bare 45cm kaptons connected and nothing seems to have changed from where we left last night

Waveforms in nnaida11 look good and peak widths in nnaida11 1.8.L and 1.10.L are ~70ch.

Turned off flash ADCs for all FEEs by setting Q8_transfer.vhd: 0xa00, offset 0x00, to 0 to assess any affect they may play in the observed noise

no obvious change in peak widths for nnaida11

turned all back on by resetting value of offset 0x00 to 1

Measured RMS deviation of waveform baseline for nnaida11 with 45cm unshielded kapton connected by sampling waveform every 10 samples over 100 samples, i.e. every 200ns for 2us.

1.4.W      -     mean:    8612.9            st. dev.:     20.5

1.6.W      -     mean:    8548.9            st. dev.:     16.6

1.8.W      -     mean:    8900.8            st. dev.:     16.2

1.10.W    -     mean:    8744.5            st. dev.:     15.0

Removed kapton to check intrinsic RMS deviation of pre-amp using the same method

1.4.W      -     mean:    8666.8            st. dev.:     4.7

1.6.W      -     mean:    8586.6            st. dev.:     2.0

1.8.W      -     mean:    8918.7            st. dev.:     3.2

1.10.W    -     mean:    8782.3            st. dev.:     4.2

These results are consistent with the pulser peak widths observed with/without Kapton PCBs attached

Make a makeshift screening plate for the adapter PCBs using the Cu tape -> widths in nnaida11 all slightly worse but still comparable.

Connected detector using 4 45cm kaptons (gnd via nnaida13) and baised via nnaida12+13 to +200V with a leakage current of 5.16uA (Room temp 24.2oC)

Initially observed very noisy waveforms but grounding adapter PCBs together improved the noise slightly but not to an acceptable level (see attachment 2+3).

Measure the peak width as a function of shaping time:

t_shape:             0.5   |   1.0   |   2.0   |   4.0   |   8.0

FWHM (ch):     308    |   352  |  345  |   252  |  130

Throughout, the peaks were non-Gaussian and double peaked with single peak widths ~50-70ch.

Pickup effect rather than white noise?

Shielded kapton to nnaida11 with Cu tape and found noise to decrease slightly when grounded to LEMO connector on adapter PCB - bursts reduced in amplitude but persistent periodic noise remained (see attachments 4+5).

Changed grounding around (adapters to NIM crate, adapters to detector box etc) and observed no noticeable difference.

However, removing jumpers grounding PCBs to FEE cards and the grounding between the adapter PCBs makes the noise worse.

Shielded 3 more 45cm kaptons and connected detector -> no leakage current.

Found several pins on 2 kaptons to be broken. Will get these fixed in Edinburgh for use next week.

Reconnected old kaptons and system is as expected - slower rise time in waveforms but reasonable levels of noise and expected peak widths (see attachment 6).

Note: kapton #7 may have broken pins next to (deliberately) broken ground pin. Unclear, but should not be used for bias until certain.

Detector BB18 2998-22 connected via 4 45cm kaptons and biased to +200V via nnaida12+14, with leakage current 4.310uA @ room temp 25.4oC.

Turned off FADCs as per PCS instructions in previous entry - no change. Turned back on.

Braid grounding HV to pulser and all jumpers removed - makes performance much worse.

Connecting only jumper to ground detector brings performance back to moderate, but not good. Re-adding braid bring further improvement.

         - other jumpers don't seem to have a considerable affect on performance.

Added short (~few cm) drain wire to outside of Cu tape covering kaptons and attached to nearest allen bolt in adapter PCB, i.e. at the top of each connector, plus the jumper for the detector ground. Looked at variation with shaping time:

                 t_shape (us)     ||    0.5    |     1.0    |     2.0     |     4.0     |     8.0

       Pulser FWHM (ch)     ||    715  |    687    |     448    |    246    |     124        (nnaida14)

       - all peaks were non-Gaussian and double peaked apart from at 8us. @ 8us it was not quite Gaussian, but much closer than the rest.

Added ~20cm drain wires to each kapton and connected all at one point on mount screw above nnaida14 adapter PCB connector. Again looked at variation with shaping time.

                 t_shape (us)     ||    0.5    |     1.0    |     2.0     |     4.0     |     8.0

       Pulser FWHM (ch)     ||    363  |    354    |     245    |    120    |     85        (nnaida14)

     - again, at low shaping times all peaks started out double peaked, but moved closer to Gaussian as t_shape was increased. At 8us, not quite Gaussian, but close.

P-side performance much better than n-side.

        - currently drain wires are connected to p-side adapter PCB. Will move these to n-side PCB tomorrow to see if this has any affect.

Current nnaida12 (MAC address 2b:09:e8) has several noisy channels in ASICs 1-3, whilst ASIC4 does not work at all.

Frequently, but not always, ASIC4 fails to load/check.

Additionally, fast discriminators are turned off in settings but show activity in the Hit spectrum.

When trying to calibrate FADCs in FADC Align and Control page, ticked 'Act on ALL FEE64 modules'.

Error message displayed (attachment 1) and, despite 'Act on ALL' box being ticked, was only able to act on one FEE64 at a time.

Powered system on from the state it was in last night. Biased to +200V with leakage current 3.9uA at room temp 22.8oC.

Performance of nnaida14 at shaping time of 8us slightly worse than last night - peak now non-Gaussian and double peaked. New source of noise?

Trying different permutations of grounding options initially led to no improvements.

         - tried various jumper combinations and taking the braids from the kaptons to various different points on the adapter PCBs - no appreciable changes.

However, connected the braids from the kaptons to the thick Cu braid with a crocodile clip and the noise in the back side FEEs significantly reduced.

Throughout, both sides of the detector saw improvements, but the front side performed much better than the back (rear waveforms were still just noise, just slightly reduced noise).

Soldered 4 drain wires to the  thick Cu braid to improve connection and taped them to the Cu tape on the kaptons so as to give the shortest possible distance between kapton and thick braid (attachment 2).

          - performance in nnaida11 improved dramatically, the waveforms looked sensible instead of just noise (see attachment 1)

          - however, nnaida14 waveforms have now just gone to noise... We have swapped the performance of the front/rear strips.

In investigating this, we have found poor connections and high resistance between the Cu blocks and adapter PCBs, despite all screws connecting them -> a good connection cannot always be assumed it seems.

However, taking a braid from the PCBs directly to the Cu blocks makes little difference to performance. Neither did putting an Al plate on the front of the detector.

The Al detector box was previously floating, but now is not - the effect of this will be investigated tomorrow.

Powered on system without issue. biased detector to -200V. Leakage current not stable, bouncing around between ~3.66 - 3.74uA. Room temp 22.0oC    -> Peak widths similar to yesterday.

Changed through various permutations of jumper connections (field planes, detector grounds, bias ground reference).

The only change that led to any change in performance was the removal of the bias ground reference jumper, this made the waveform noise much worse and increased peak widths (attachment 4).

Changed the network cables to unshielded (no ground connection) ones. No difference in performance.

Connecting thick Cu braid from NIM bin chasis to LEMO connectors makes noise worse.

Moving this braid to the PSU case made peak widths larger and waveform noise in nnaida14 much worse. Traces do not return to baseline after a pulser event (attachment 2+3)

Reduced bias to -100V in an attempt to stabilise the jumpy leakage current -> made it worse.

Increased to -250V and the leakage current stability improved -> fluctuations of < 0.10uA @ 4.985uA.

Connected Al detector box with thick braid to braid connecting HV and pulser input -> no difference.

Replaced metal detector box with cardboard box so it was floating -> no difference.

Made sure kaptons were all separated with sheets of paper to prevent electrical contact of shielding -> no difference.

Disconnected detector and found double-peaking remains => this is not a detector issue, but intrinsic to the kaptons (with the kaptons removed, we observe Gaussian peaks of width ~14ch) (attachments 5-9).

Occasionally, waveforms fail to reset correctly (attachment 7).

Cu mezzanine block and Al crate now no longer isolated from each other. Resistance between them ~6 Ohms with crate locked up, increases to ~300kOhms when crate opened.

The RPi power cable cannot sit fully in the connector, and the lock pins can't engage, because the case gets in the way of the plastic around the end.

As a result we have knocked it out a couple of times and lost power to the system.

Can this be modified or can we get a new case/cable that resolves this issue?

Spent whole day trying to isolate mezzanines from cooling crate.

Finally managed to increase resistance between crate and mezzanines from ~5 Ohms to ~380 kOhms with some masking tape and parcel tape over the slots in the FEE modules in which rest the guide pins on the bottom of cooling crate.

See excellent performance in nnaida11, with peak widths down to ~45ch and almost perfectly smooth waveforms.

         - this is with just the kaptons connected (all of which are shielded with tape) and no detector. Shaping time of 8us.

Performance in other FEEs remains largely unchanged. (Note: Yesterday saw similar performance in nnaida13+14 for 15mins but lost it and couldn't regain same performance.)

Turned off cooler to see what effect that had - no major changes to peak widths.

Turned off cooler and loosened crate lid - again no appreciable difference.

=> It seems this electrical connection between cooling crate and mezzanines could be the source of a lot of our noise.

Could remove pins completely to see effect that has, before trying with plastic ones when they arrive.

Attachment 1 shows FADC monitor during period in which ADCs in nnaida14 were not calibrated correctly.

 12/01/16      (Attachments 1-8)

FEEs set up as per ELOG entry 136 (15/12/15)

Connected cables as follows:

     - nnaida11 > LH coupler + 45cm ribbon (unshielded)

     - nnaida12 > no load (no waveforms from this card)

     - nnaida13 > LH coupler + 45cm ribbon (unshielded) + RH coupler

     - nnaida14 > LH coupler

Peak widths (ch):         <all with shaping time of 8us and heavy duty Cu braid between test inputs on each adapter card>

                     nnaida11  |  nnaida12  | nnaida13  |  nnaida14

     1.4.L   |        392       |       14.7       |      250       |      34.3 

     1.6.L   |       300        |       13.6       |      150       |      23.1

     1.8.L   |       290        |       13.0       |       123      |      16.8

    1.10.L  |       309        |       13.2       |       129      |  no output

     > widths greater than expected

     > thought it could possibly be due to pickup of external noise in the room so added Cu tape as shielding to cable connected to nnaida13 with drain wire connected to CU braid on pulser input

     > reduced peak with in nnaida13 to ~160ch

     > connecting far end of Cu shielding via a Cu braid to main Cu braid reduces this to ~130ch

     > connecting Cu shielding on RH coupler to main ribbon cable shielding with thin braid reduced this further to ~110ch

For nnaida13, see double peaking of pulser peak with all shaping times up to 2us. At 4us, see single peak of width ~160ch. At 8us, see single peak of width ~110ch.

13/01/16      (Attachments 9-20)

Set up system as yesterday.

With shaping time of 2us, nnaida13 does not show Gaussian peaks. Some peaks are double, others just single non-Gaussian peaks.

Yesterday peak-to-peak difference was ~150ch

    - added tin foil to loose coupler end and over connection between ribbon cable and RH coupler, as it was suspected it could be pickup of external noise

    - @ 2us shaping time, double peaks still present with p-2-p difference of ~130ch

    - clipped foil firmly to Cu shielding tape  >  no difference.

In nnaida14, see single roughly Gaussian peak of width ~15ch.

In nnaida11, see single peaks of widths ~250ch. At 8us this reduces to ~180ch.

Connecting the Lk7 jumper for nnaida13 produces no difference.

Added full LH coupler + 45cm ribbon + RH coupler to all nnaida, with full shielding > no improvement.

Connected all to detector and saw no improvements, in fact increased noise in nnaida13 dramatically (see waveforms)

See low frequency wave in waveforms, will work next week to try remove this as this could be what is causing the double peaking and hiding the true capabilities of the cables.

18.00 Swapped input cables to nnaida11 and nnaida14
      both cables LH coupler + 2x 34-way Samtec ribbon cables + 3M 1245 1.4mil Copper screen w/ground wire
      RH coupler not fitted 
      both ground wires tied to BNC cable from pulser to AIDA adaptor PCBs at BNC(F)-Lemo-00(M) adaptor

      Before swap, input cable attached to nnaida11 exhibited typical peak widths ~50 ch FWHM, cable
      attached to nnaida  exhibited double peaking and other structure

      This is unchanged following swap => grounding and/or AIDA adaptor PCB significant *not* cable

      See attachments 1-4 post swap  
       nnaida11 ASIC 2*L ~40-60 ch FWHM pulser peak width
       standard ASIC settings, shaping time 2us