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- Dried Seed Timer by the Jolly Roger
-
- A time delay device for electrical firing circuits can be made using
- the principle of expansion of dried seeds.
-
- Material Required:
- -----------------
-
- Dried peas, beans, or oter dehydrated seeds
- Wide-mouth glass jar with non-metal cap
- Two screws or bolts
- Thin metal plate
- Hand drill
- Screwdriver
-
- Procedure:
- ---------
- 1) Determine the rate of the rise of the dried seeds selected. This is
- necessary to determine the delay time of the timer.
- a) Place a sample of the dried seeds in the jar and cover with
- water.
- b) Measure the time it takes for the seeds to rise a given height.
- Most dried seeds increase 50% in one to two hours.
- 2) Cut a disc from thin metal plate. Disc should fit loosely inside the
- jar.
-
- NOTE: If metal is painted, rusty, or otherwise coated, it must be scraped
- or sanded to obtain a clean metal surface
-
- 3) Drill two holes in the cap of the jar about 2 inches apart. Diameter
- of holes should be such that screws or bolts will thread tightly into
- them. If the jar has a metal cap or no cap, a piece of wood or plastic
- (NOT METAL) can be used as a cover.
- 4) Turn the two screws or bolts through the holes in the cap. Bolts
- should extend about one in. (2 1/2 cm) into the jar.
-
- IMPORTANT: Both bolts must extend the same distance below the container
- cover.
-
- 5) Pour dried seeds into the container. The level will depend upon the
- previously measured rise time and the desired delay.
- 6) Place the metal disc in the jar on top of the seeds.
-
- How to use:
- ----------
-
- 1) Add just enough water to completely cover the seeds and place the cap
- on the jar.
- 2) Attach connecting wires from the firing circuit to the two screws on
- the cap.
-
- Expansion of the seeds will raise the metal disc until it contacts the
- screws and closes the circuit.
-
- ---------------------Jolly Roger
-
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- Downloaded From P-80 International Information Systems 304-744-2253
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