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Message ID: 5742     Entry time: Wed Oct 26 11:35:08 2011
Author: Katrin 
Type: Update 
Category: Green Locking 
Subject: YARM PDH box 

PDH_w_wo_jump.png

From time to time the 20 dB jump in the transfer function still occurs. The new AD8336 op amp did not change that issue. I am sure that the op amp was broken,

because the amplitude of the sine did not change when I turned the gain knob.

The above two curves were measured with different input amplitude of the sine from the spectrum analyzer. Nothing changed in between except that there was no

jump when Kiwamu was around. Very strange. Testing the electronic board led to no clue what is happening.

For now, I will just use the PDH box as it is, but one should keep this odd behaviour in mind.

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