Lena/Oct 2016
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October 2016
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10/03/2016
fMCG setup TODO
- Feedback system to keep the fields from "running away". Only the main XYZ fields need to be stabilized, the gradients don't change much day to day
- Reduce the polarimeter noise when misbalanced
Eliminating polarimeter noise when misbalanced
The existing current amplifier consists of two photodiodes connected in a way to add or subtract their photocurrents. The output of this passive circuit is connected to an SR570 current preamplifier.
I want to replace this circuit with something that can output both sum and difference, so that the common mode variations can be cancelled. Apparently a circuit that is supposed to do that has already been designed (see the link). The circuit has very little documentation and needs to be modified to increase the gain.