I have made a design for a simulator. I need your help and input on how to make it better. I have two separate circuits, both use the 5k
pot, that require 24VDC (current) and 12VDC (freq.). The first circuit (top) is the freq. generator, the second is the 4-20mA (bottom).
The switch (SW1) is used to go full scale (20mA) with a push of a button.
I have added the NPN transistors to act like a switch as to isolate the 555 timer from 24VDC. Any help
would be appreciated.
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