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Entry  Thu Jul 3 18:48:09 2008, Alberto, Update, General, Beats of the two lasers in the absolute length measurement observed  
    Reply  Thu Jul 3 22:54:45 2008, Koji, Update, General, Beats of the two lasers in the absolute length measurement observed  
       Reply  Mon Jul 7 11:22:02 2008, Alberto, Update, General, Beats of the two lasers in the absolute length measurement observed  
          Reply  Mon Jul 7 13:06:38 2008, Koji, Update, General, Beats of the two lasers in the absolute length measurement observed  
Message ID: 638     Entry time: Mon Jul 7 13:06:38 2008     In reply to: 637
Author: Koji 
Type: Update 
Category: General 
Subject: Beats of the two lasers in the absolute length measurement observed  
One may need an RF filter after the mixer. I expect the SR560 does work for this purpose.
If it does not, a passive LPF can be used.


Quote:
I didn't post a screenshot from the RF SA because I had troubles with the interface with the computer (unfortunately the network SA cannot export the data).

There's is problem with the PLL circuit. The signal, beside the beat, also contains peaks at 33, 66 and 99 MHz, so we should think about filtering those out, correct?
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