BIGFOOT (Readout)
ShalikaSingh - 07:56, Monday 18 November 2024 (3839)
Measuring output of EOM resonant circuit

I modified the circuit to match impedance with mokugo. Seems moku go only has impedance of 1M ohm and not 50ohm. So, I added 1Mohm (previously 50ohm) infront of Opamp and 10Mohm (previously 1.1k) on the feedback. I measured the voltage output after the opamp (CH1) and before the EOM (CH2). The EOM was connected to the circuit during this measurement. 

The output doesn't match the expectation. Since I input 0.05V p-p from moku, I should get 0.5V after Opamp circuit (coz its gain is 10). But I get output as 8V both after the opamp circuit and before EOM. The picture is from the oscilloscope. 

Maybe its because I left ground floating when I soldered the SMA cables. 

Images attached to this report
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