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Entry  Fri Nov 4 13:04:50 2011, Zach, Update, Green Locking, Passive summing box modifications sum_circuit_new.pngsumbox_TFs.png
    Reply  Sat Nov 5 04:30:21 2011, kiwamu, Update, Green Locking, Re:Passive summing box modifications 
Message ID: 5820     Entry time: Sat Nov 5 04:30:21 2011     In reply to: 5807
Author: kiwamu 
Type: Update 
Category: Green Locking 
Subject: Re:Passive summing box modifications 

I think you also should check the PZT's capacitance of the 700mW LightWave because 2.36 nF is the one for the 1W Innolight laser.

Quote from #5807

To combat this, I propose we simply change the resistor in the modulation path from 1M to 10k. This leaves the feedback path TF unchanged, and changes the mod path into a sort of bandpass filter for the modulation frequency. The fact that the phase is near zero at fmod means we don't have to come up with some way to phase shift the signal for demodulation.

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