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Entry  Thu Mar 5 12:27:27 2015, manasa, Update, General, FOL fiber box on the PSL table 
    Reply  Fri Mar 6 14:29:59 2015, manasa, Update, General, FOL troubleshooting 
       Reply  Mon Mar 9 14:43:31 2015, manasa, Update, General, FOL troubleshooting FOL_trouble.pdfIMAG0341.jpgIMAG0342.jpg
          Reply  Tue Mar 10 17:48:07 2015, manasa, Update, General, FOL troubleshooting 
             Reply  Wed Mar 11 19:48:25 2015, Koji, Update, General, FOL troubleshooting 
                Reply  Thu Mar 12 11:57:38 2015, Koji, Update, General, FOL troubleshooting 
Message ID: 11110     Entry time: Fri Mar 6 14:29:59 2015     In reply to: 11102     Reply to this: 11123
Author: manasa 
Type: Update 
Category: General 
Subject: FOL troubleshooting 

[EricQ, Manasa]

Domenica:
Since Domenica was not picking up an IP address and hence not responding to pings or ssh even after power cycling, I pulled it out from the IOO rack and connected it to a monitor. After a bunch of hit and trials, we figured out that the problem was related to the power adapter of the Rpi discussed here : http://www.raspberrypi.org/forums/viewtopic.php?f=28&t=39055

The power adapter has been swapped and this issue has been resolved. Domenica has been remounted on the IOO rack but left with the top lid off for the timebeing.

RF amplifier box:
The frequency counter was setup to read the beat frequency after amplification of the RFPD signals. The output as seen on the frequency counter screen as well as the epics values was intermittent. Also, locking the arms and changing the end laser frequencies did not change the frequency counter outputs. It looks like the RF amplifier is oscillating (Oscillating frequencies were ~107 MHz and 218 MHz) and the input circuit needs to be modified and the connections need better insulation.

As of now, I have connected the RFPD outputs to the frequency counter sans any amplification and we are able to get a readout of the beat frequency at > 40MHz (Frequency counter requires much higher amplitude signals for frequencies lower than that).

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