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Old 04-03-2007, 07:38 PM
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kwirky kwirky is offline
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just an update.

I got the prototype working. It's adjustable from 5 seconds to 1.5 minutes for each pump, and I have a switch that will shut off all the pumps for 3 minutes for feeding.

I tried to get the 555 to go through a JK flip flop for a 50% duty cycle, but output (O) of the JK chip doesn't actually reach 0 V/I, so it wouldn't trigger the amplifying transistor to shut off. So I only used the 555 with a resistor combo that gives as close to a 50% duty as possible.

When the final circuit board is soldered up, I'll post pics schematic diagrams. I'll have enough parts left over too in case anyone wants me to build them one or two. I'd do it for pretty cheap.
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Last edited by kwirky; 04-03-2007 at 08:00 PM.
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