I am using a guitar pickup to act as an on off switch for a synthesizer I am building.
The pickup produces an analog signal when the string is vibrating, my plan is to turn this into a DC signal with a rectifier, then use a comparator to compare that to a set DC voltage reference. The output from the comparator will be sent to a Basic Stamp 2.
My confusion is where to put all the grounds for this system. In order to see the DC voltage from the rectifier, I need to measure across the rectifier terminals, but the comparator needs to be able to see this voltage in order to make the comparison, and I do not think I can just put the negative terminal from the rectifier into the comparator (as it has the same ground as the pickup's ground).
I have tried a few different ways of connecting grounds, but each didnt seem to work correctly.
Schematic is attached.
The pickup produces an analog signal when the string is vibrating, my plan is to turn this into a DC signal with a rectifier, then use a comparator to compare that to a set DC voltage reference. The output from the comparator will be sent to a Basic Stamp 2.
My confusion is where to put all the grounds for this system. In order to see the DC voltage from the rectifier, I need to measure across the rectifier terminals, but the comparator needs to be able to see this voltage in order to make the comparison, and I do not think I can just put the negative terminal from the rectifier into the comparator (as it has the same ground as the pickup's ground).
I have tried a few different ways of connecting grounds, but each didnt seem to work correctly.
Schematic is attached.
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