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Entry  Wed Feb 11 18:11:46 2015, Koji, Summary, LSC, 3f modulation cancellation 
    Reply  Thu Feb 12 23:47:45 2015, Koji, Update, LSC, 3f modulation cancellation 
       Reply  Sat Feb 14 00:48:13 2015, Koji, Update, LSC, 3f modulation cancellation 
          Reply  Sat Feb 14 19:54:04 2015, Koji, Summary, LSC, 3f modulation cancellation beat_setup1.JPGbeat_setup2.JPGelectrical_setup.pdf
             Reply  Sat Feb 14 20:37:51 2015, Koji, Summary, LSC, 3f modulation cancellation beat_pd_response.pdfbeat_nominal.pdf3f_reduction.pdfbeat_3f_reduced.pdf
                Reply  Sat Feb 14 22:14:02 2015, Koji, Summary, LSC, [HOW TO] 3f modulation cancellation freq_gen_box.JPGdelay_line.JPGcable_spec.pdf
                   Reply  Sun Feb 15 16:20:44 2015, Koji, Summary, LSC, [ELOG LIST] 3f modulation cancellation 
                      Reply  Sun Feb 15 20:55:48 2015, rana, Summary, LSC, [ELOG LIST] 3f modulation cancellation 
                         Reply  Mon Feb 16 00:08:44 2015, Koji, Summary, LSC, [ELOG LIST] 3f modulation cancellation 
                   Reply  Mon Feb 16 01:45:12 2015, Koji, Summary, LSC, modulation depth analysis modulation_nominal.pdfmodulation_3f_reduced.pdf
Message ID: 11035     Entry time: Mon Feb 16 00:08:44 2015     In reply to: 11034
Author: Koji 
Type: Summary 
Category: LSC 
Subject: [ELOG LIST] 3f modulation cancellation 

This KTP crystal has the maximum allowed RF power of 10W (=32Vpk) and V_pi = 230V. This corresponds to the maximum allowed
modulation depth of 32*Pi/230 = 0.44. So we probably can achieve gamma_1 of ~0.4 and gamma_2 of ~0.13. That's not x3 but x2,
so sounds not too bad.

Then Kiwamu's triple resonant circuit LIGO-G1000297-v1 actually shows the modulation up to ~0.7. Therefore it is purely an issue
how to deliver sufficient modulation power. (In fact his measurement shows some nonlinearity above the modulation depth of ~0.4
so we should keep the maximum power consumption of 10W at the crystal)

This means that we need to review our RF system (again!)

- Review infamous crazy attn/amp combinations in the frequency generation box.
- Use Teledyne Cougar ampilfier (A2CP2596) right before the triple resonant box. This should be installed closely to the triple resonant box in order to
minimize the effects of the reflection due to imperferct impedance matching.
- Review and refine the triple resonant circuit - it's not built on a PCB but on a universal board. I think that we don't need triple
resonance, but double is OK as the 29.5MHz signal is small.

We want +28V supply at 1X1 for the Teledyne amp and the AOM driver. Do we have any unused Sorensen?

ELOG V3.1.3-