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Ke maintanance trip: backend


- mk5ke is supplied with a 1200W Smart power supply.

- mk5ke was successfully tested for recording and conditioning with two 16-TB modules.

- mk5ke and mk5-2ke: recording, conditioning, autocorrelation, bit stats and pcal tests (pcalmon) were performed with both mk5's, swapping VSI cables and FILA OUT VSI outputs.

- Pcal 5-MHz filter: tested, found to create fast phase wrap and introduce spurious signal in channels 5, 15, 16, thus discarded (pic – pcalmon output graphs).

- Pcal: pcal synch tone connected directly to the maser past the 5-MHz distributor. Levels regulated at the feed: added 3-dB attenuator to S-band. Current attenuation is 15dB in S-band, 0dB in X band. Amplitudes of the pcal signal before DBBC: X-band ~18dB, S-band ~15dB.

- DBBC: FILA OUT and Core2 boards inspected, connections checked. Secured VSI cables inside the DBBC with cable holders in order them not to pull on the VSI connectors.

Problems revealed:

- mk5ke: pcal signal extracted from the data recorded with mk5ke is “stuck” at one level, doesn't vary with time (under the same conditions the signal from mk5-2ke looks “naturally”). Problem is nether related to a cable nor to the VSI connectors on FILA OUT. VSI IN connector on the back of mk5ke?

- mk5ke and mk5-2ke: refuse to condition just one module. Always conditions module in bank B when two modules are in, both VSN's are lost. Recommendations for use: when conditioning, put the module to be conditioned in bank B. Put dummy erased module in bank A. Condition as normal. Swap modules if necessary. After conditioning, repair electronic VSNs of both modules.

- Pcal: all tones over the passband are visible on spectrum analyser, but 10-kHz are suppressed by DBBC (pic pcalmon output).

- DBBC: “stuck bit” and bit statistics problems related to VSI OUT connectors: ch15 (S) with VSI1 (rear) – was problematic from the beginning, ch5 (X) with VSI2 (front) emerged after the inspection and refitting of FILA OUT board.

- Modules: hob+025/6000 was found to have faulty disk among 6/7. Is labeled as broken and prepared for repair.

log monitor now checks for FS activity

The PCFS Log monitor now checks the Field System log to see when the last entry was. If it's more than 15 mins ago it will ring a beep every 2 seconds as this is a possible sign that the Field System software has dies or that the network has dropped out.

Also removed the check to see if time had gone backwards. This check was buggy and doesn't seem to actually trap a real problem.

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/home/www/auscope/opswiki/data/attic/blog/log_monitor_now_checks_for_fs_activity.1403402017.txt.gz · Last modified: 2014/06/22 01:53 by liza