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Entry  Fri Nov 14 19:20:42 2008, Yoichi, Update, PSL, Reference cavity ring down RingDown.png
    Reply  Fri Nov 14 20:35:47 2008, rana, Update, PSL, Reference cavity ring down 
       Reply  Fri Nov 14 22:40:51 2008, Yoichi, Update, PSL, Reference cavity ring down 
          Reply  Mon Nov 17 15:07:06 2008, Yoichi, Update, PSL, Reference cavity ring down Fit.png
Message ID: 1138     Entry time: Fri Nov 14 22:40:51 2008     In reply to: 1137     Reply to this: 1140
Author: Yoichi 
Type: Update 
Category: PSL 
Subject: Reference cavity ring down 

Quote:

To make the DEI pulser make a fast pulse on the EO shutter EOMs, we had to make sure:

1) the cable had a high voltage rated dielectric. cheap dielectrics show the 'corona'
effect, especially when there is a bend in the cable.


I'll check it with Bob.


Quote:

2) the EO has to have a resistor on it to prevent ringing due to the impedance mismatch.


Did you use a shunt or series resistor ?
If shunt, I guess it has to have a huge heat sink.
Actually, DEI says the pulser does not require any external shunt/series resistors or impedance-matching network.
Looks like it is not true ...


Quote:

3) We needed ~3.5 kV to get the EO shutter crystal to flip the light by 90 deg.


Yes, I adjusted the voltage to maximize the power change and it was about 3.5kV.
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