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Entry  Wed Aug 12 18:08:54 2020, gautam, Update, Electronics, Number of the beast IMG_8710.JPG
    Reply  Wed Aug 12 20:15:42 2020, Koji, Update, Electronics, Number of the beast 
    Reply  Tue Sep 15 12:20:36 2020, gautam, Update, Electronics, SR785 repaired dividerTF.pdf
Message ID: 15517     Entry time: Wed Aug 12 18:08:54 2020     Reply to this: 15519   15571
Author: gautam 
Type: Update 
Category: Electronics 
Subject: Number of the beast 

The "source" output of the SR785 has a DC offset of -6.66 V. I couldn't make this up.

Upshot is, this SR785 is basically not usable for TF measurements. I was using the unit to characterize the newly stuffed ISC whitening board. The initial set of measurements were sensible, and at some point, I started getting garbage data. Unclear what the cause of this is. AFAIK, we don't have any knob to tune the offset - adjusting the "offset" in the source menu, I can change the level of the offset, but only by ~1 V even if I apply an offset of 10 V. I also tried connecting the ground connection on the rear of the SR785 to the bench power supply ground, no change.

Do we have to send this in for repair?

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