In the attached image, Diagram A shows a working circuit of a Spark Fun Opto Isolator break out board using 1 power source for both input and output. Diagram B shows a working circuit of a Opto Isolator board using 2 power sources, one for input and one for output. Diagram C shows a NON-working circ…

Since you were a first time poster, you may have been prevented from attaching files. Try again now that I’ve approved your first post. -Bill

Thanks Bill! Here is the Diagram of the 3 circuits and a recap of the issue… Diagram A shows a working circuit of a Spark Fun Opto Isolator break out board using 1 power source for both input and output. Diagram B shows a working circuit of a Opto Isolator board using 2 power sources, one for inpu…

If I follow the schematic of the board ([ <LINK_TEXT text=“https://www.sparkfun.com/datasheets/Bre … or-v12.pdf”>https://www.sparkfun.com/datasheets/BreakoutBoards/Optoisolator-v12.pdf</LINK_TEXT> ), I think you’re connecting e.g. JP1 / pin4 to JP2 / pin3. If so, the 10K pullup-resistor on the collec…

Opto Isolators in Series

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cheezwhiz January 20, 2016, 12:56am 5

Thank you very much sterretje

I added a 2n3904 transister between the opto isolator boards and it now passes the signal…

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Opto Isolators in Series

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