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Entry  Thu Jul 22 14:07:20 2010, kiwamu, Update, PSL, PSL front end machine PSL-PMC2010-07-22.png
    Reply  Thu Jul 22 15:59:29 2010, Alberto, Update, PSL, PSL front end machine 
       Reply  Thu Jul 22 18:18:54 2010, Alberto, Update, PSL, Problem Solved 
          Reply  Fri Jul 23 00:13:11 2010, rana, Update, PSL, Problem NOT REALLY Solved 
Message ID: 3269     Entry time: Thu Jul 22 15:59:29 2010     In reply to: 3268     Reply to this: 3270
Author: Alberto 
Type: Update 
Category: PSL 
Subject: PSL front end machine 

Quote:

It looks like something wrong happened around the PSL front end.  One of the PSL channel, C1:PSL-PMC_LOCALC, got crazy. 

We found it by the donkey alarm 10 minutes ago.

The attached picture is a screen shot of the PMC medm screen.

The value of C1:PSL-PMC_LOCALC ( middle left on the picture ) shows wired characters. It returns "nan" when we do ezcaread.

Joe went to the rack and powered off / on the crate, but it still remains the same. It might be an analog issue (?)

The problem seems to be a software one.

In any case, Kiwamu and I looked at the at the PMC crystal board and demod board, in search of a possible bad connection. We found a weak connection of the RG cable going into the PD input of the demod board. The cable was bent and almost broken.

I replaced the SMA connector of the cable with a new one that I soldered in situ. Then I made sure that the connection was good and didn't have any short due to the soldering.

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