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Gordon Dabbled in Backyard Water Sports

Article-Gordon Dabbled in Backyard Water Sports

Gordon Dabbled in Backyard Water Sports

Not satisfied with the flow rate he was able to achieve with his Super Soaker, Gordon decided to upgrade to a backyard dunk tank. By hooking up an off-the-shelf sump pump to a power supply and building in microprocessor control, he can blast a victim with up to 5 gallons of water when the target is hit. Switch inputs control the "douse" time from one to nine seconds. The microprocessor clocks data into a shift register to control the seven-segment time display. For easy disassembly and transport (it's great for office parties!), the frame is constructed of 1.5-inch PVC tubing screwed together.

"Sump" tank parts list
Amt Part Description Allied Part #
1 Circuit Board 0.1 grid 4 X 5 inch 237-0119`
1 Plastic Box (Serpac 131) 882-1131
1 10 K V Resistor, 1/4W, 5% 296-5586
1 1 K V Resistor, 1/4W, 5% 296-5562
7 470 V Resistor, 1/4W, 5% 296-5548
1 Shift Register (74HCT164N) 236-1759
1 7-Segment Display 782-0425
1 Octal Buffer (74HCT244N) 236-1775
3 Terminal Block 1 X 2 409-0111
1 Transistor 2N2222 248-1004
1 LM578M05CT Regulator, 5V Pos 288-0004
1 1N5400 Rectifier Diode 266-0008
1 Capacitor, 220 F, 25Vdc 852-7030
1 1N914 Diode 431-0618
1 Relay (10A, SPST, 5V) 788-1079
1 Power Supply 12Vdc 879-0215
1 General Purpose Snap Action Switch 821-1569
1 Pushbutton Switch for Changing Time 948-7193
Additional parts required: 8-pin Microprocessor PIC12F229, sump pump, PVC tubing, assembly hardware

For PDF links to Gordon Wall's instructions and drawings:

Dunk tank information
Sump pump directions
Dunk tank B.O.M.
Schematic drawing of sump tank
Schematic drawing of modified outlet

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