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Message ID: 2358     Entry time: Mon Jun 24 14:00:40 2019
Author: ScottA 
Type: DailyProgress 
Category: EOM 
Subject: Bias Tee Addition 

EOM Bias Tee:

  • I will make use of the RF Monitoring Circuit present on the driver for high impedance probing, which should have a coupling factor of about -36db at 37MHz. 
  • I want to model the EOM as a capacitive load, which from the data sheet is 20pF. We will use a board to solder a BNC port to this capacitor, and short the other side to ground. 
  • We want to measure the transfer function before and after the addition of a Bias Tee, and use the RF Monitor to tune the inductor to create an impedance peak at 37MHz.

    The first diagram shows the set-up without the Bias Tee. Here we will confirm the monitoring out channel is functional and the dummy EOM acts as expected. After we will add the Bias Tee as shown in the second diagram. Using the monitoring channel again we can then see the effect of adding the Bias Tee to the output of the amplifier circuit, but before the dummy EOM.

Attachment 1: EOM_driver_schematic.pdf  14 kB  Uploaded Mon Jun 24 19:11:31 2019  | Hide | Hide all
EOM_driver_schematic.pdf
Attachment 2: EOM_driver_schematic_with_bias_tee.pdf  24 kB  Uploaded Mon Jun 24 19:11:38 2019  | Hide | Hide all
EOM_driver_schematic_with_bias_tee.pdf
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