i threw together a driver for the air pump with what i had on hand: a 2n3904 transistor with 1.2k (anything 1k-3k will work) base resistor and a 10 ohm series resistor for the motor and a 1n4148 snubber diode directly across the motor. the final version will be more robust, i'm sure. this is something like $0.10 worth of parts.


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