40m QIL Cryo_Lab CTN SUS_Lab CAML OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  ATF eLog  Not logged in ELOG logo
Entry  Wed May 13 16:57:28 2009, Dmass, Laser, PMC, Relocking the PMC 
    Reply  Thu May 14 20:57:22 2009, rana, Laser, PMC, Relocking the PMC 
       Reply  Fri May 15 04:23:19 2009, Dmass, Laser, PMC, Relocking the PMC Pmclock.png
Message ID: 127     Entry time: Thu May 14 20:57:22 2009     In reply to: 125     Reply to this: 128
Author: rana 
Type: Laser 
Category: PMC 
Subject: Relocking the PMC 
  • Instead of using the polarizer all the way, set the polarizer to transmit a few W and then use a fixed BS to attenuate down to 10-30 mW before doing the PMC alignment.
  • The ZAD-6 is a level 7 mixer so you have to give it 7 dBm. So there should be no attenuator after the splitter for the LO.
  • Have to AC couple (or DC block) the PDA signal before going into the mixer. It wants AC only.
  • The mixer output should go into the 1.9 MHz low pass and then get terminated with 50 Ohms (like with a T). Then the other output of the T can go to the DAQ or into the SR560 for some gain but you shouldn't need very much gain. Certainly the SR560 should have no filter clicked on.
  • If you use the SR560, make sure the output is zero with no light on the PD. There's a trim pot on the front.
  • In the digital world there should be a single pole around 1 Hz. Make sure the output actually goes to the PZT driver.
ELOG V3.1.3-