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Entry  Wed May 12 23:31:17 2010, Alberto, Update, 40m Upgrading, 216 MHz resonance in the POY11 PD killed POX11.png2010-05-12_POY11_CalibratedOpticalResponse0-500MHz.png
    Reply  Thu May 13 05:06:43 2010, rana, Update, 40m Upgrading, 216 MHz resonance in the POY11 PD killed 
Message ID: 2926     Entry time: Thu May 13 05:06:43 2010     In reply to: 2925
Author: rana 
Type: Update 
Category: 40m Upgrading 
Subject: 216 MHz resonance in the POY11 PD killed 

 

 This idea was tried before by Dale in the ~1998 generation of PDs. Its OK for damping a resonance, but it has the unfortunate consequence of hurting the dynamic range of the opamp. The 100 Ohm resistor reduces the signal that can be put out to the output without saturating the 4107.

I still recommend that you move the notch away from the input of the 4107. Look at how the double notch solution has been implemented in the WFS heads.

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