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Entry  Tue Nov 11 01:38:23 2014, Koji, Update, LSC, Notch at 110MHz twin_t_notch.pdfnotch_tf.pdf
    Reply  Wed Nov 12 00:55:56 2014, ericq, Update, LSC, Notch at 110MHz 165_Notched.pdf
Message ID: 10695     Entry time: Tue Nov 11 01:38:23 2014     Reply to this: 10699
Author: Koji 
Type: Update 
Category: LSC 
Subject: Notch at 110MHz 

To further reduce the RF power at 110MHz in the REFL165 chain, I made a twin-t notch in a pomona box.

It is tuned at 110.66MHz.

The inductor is Coil Craft 5mm tunable (164-09A06SL 100-134nH).
Without the 10Ohm resister (like a usual notch), the dip was ~20dB. With this configuration, the notch of -42dB was realized.

Q >> Please measure the RF spectrum again with the notch.

 

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