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Message ID: 1838     Entry time: Mon Jun 5 13:56:52 2017
Author: yinzi 
Type: Notes 
Category: DAQ 
Subject: Acromag noise measurements 

Measured the acromag noise (input and output).

For the input noise, a function generator was set up to input a sin signal of 0.1Vpp at 0.1Hz and connected to an input channel. The time series was recorded for 4 hours (sampled at around 10Hz, but not exactly due to differences in how long each loop took to run), and then the Lomb-Scargle algorithm (Fourier transform with uneven sampling) was applied to obtain a frequency spectrum. The result was then run through Andrew's rms.m script (attached). Both are plotted below:

For the output noise, a script was written to continuously write a 0.1Vpp at 0.1Hz sin signal to an output channel that was connected to the signal analyzer, which was used to take the following data.

Attachment 1: acro_out_noise.pdf  28 kB  | Hide | Hide all
acro_out_noise.pdf
Attachment 2: acro_input_plot.pdf  31 kB  | Hide | Hide all
acro_input_plot.pdf
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