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Entry  Fri Jul 24 17:47:52 2009, Stephanie, Update, General, Multiply Resonant EOM Update BuiltCkt2_Picture_Simplified.pngBuiltCkt2_Simplified.pngSimplified.png
    Reply  Sat Jul 25 13:49:28 2009, Koji, Update, General, Multiply Resonant EOM Update 
Message ID: 1787     Entry time: Fri Jul 24 17:47:52 2009     Reply to this: 1790
Author: Stephanie 
Type: Update 
Category: General 
Subject: Multiply Resonant EOM Update 

After speaking with Rana and realizing that it would be better to use smaller inductances in the flying-component circuit (and after a lot of tinkering with the original), I rebuilt the circuit, removing all of the resistors (to simplify it) and making the necessary inductance and capacitance changes. A picture of the circuit is attached, as is a circuit diagram.

A plot of the measured and simulated transfer functions is also attached; the general shape matches between the two, and the resonant frequencies are roughly correct (they should be 11, 29.5, and 55 MHz). The gain at the 55 MHz peak is lower than the other two peaks (I'd like them all to be roughly the same). I currently have no idea what the impedance is doing, but I'm certain it is not 50 Ohms at the resonant peaks, because there are no resistors in the circuit to correct the impedance. Next, I'll have to add the resistors and see what happens.

Attachment 1: BuiltCkt2_Picture_Simplified.png  434 kB  Uploaded Fri Jul 24 18:57:20 2009  | Hide | Hide all
Attachment 2: BuiltCkt2_Simplified.png  8 kB  Uploaded Fri Jul 24 18:57:58 2009  | Hide | Hide all
Attachment 3: Simplified.png  10 kB  Uploaded Fri Jul 24 18:58:36 2009  | Hide | Hide all
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