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Entry  Tue Jan 22 19:12:24 2013, tara, Notes, EOM, EOM driver IMG_2209.jpgEOM.pdf
    Reply  Wed Jan 23 19:29:26 2013, tara, Notes, EOM, EOM driver IMG_2213.jpgIMG_2214.JPG
       Reply  Wed Aug 28 20:19:44 2013, tara, Notes, EOM, EOM driver: modification driver1.jpgdriver2.jpgdriver_TF.jpg
Message ID: 1090     Entry time: Tue Jan 22 19:12:24 2013     Reply to this: 1092
Author: tara 
Type: Notes 
Category: EOM 
Subject: EOM driver 

I got an EOM driver from Rich Abbott, I'm checking if this thing works well or not.

The EOM driver is just an amplified resonant circuit with +/- 18V input. With the driver connected to a broadband (BB) EOM, we can use the combination to add sideband to the laser. This is better than a resonant EOM because we can pick a range of frequencies, instead of having a fixed one from the manufacturer.

 I checked the TF between input and the RF mon, the resonant peak can be moved between 20.7 MHz and 24.5 MHz by adjusting an inductor on the board. Since the RFPD for the PMC is 21.5 MHz, I'll use it to check the modulation index of a BB EOM equipped with this board.

The plan is 

  1. Check the power vs modulation index from the current resonant EOM. To do this, scan the laser, measure the error signal.
  2. Remove the resonant EOM, and replace it with a BB one, adjust the power, check the modulation index vs power input again

Once I verify this I will check the frequencies for refcavs and pmcs, so that I can decide the value of L and C on the board.

 

 

        IMG_2209.jpg

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