This review focuses on the manufacture of a water timer or delayed alarm. Such an alarm can be called an analogue of an alarm with a clockwork.
Before starting production, check out the author’s video
[media = https: //www.youtube.com/watch? v = Vw2M-NGy88s]
We will need:
- a test tube for blood;
- stationery buttons;
- adapter for the battery;
- light;
- glue gun;
- rechargeable battery;
- 10 ml syringe;
- stationery knife.
First of all, take a test tube, which is used for blood tests, remove the cap from it and make two holes at the edges on opposite sides.
Threaded through the holes on one push pin.
We take the adapter and wrap one of the wires on one button.
Next, take a LED bulb or any other electronic the device and wrap one of the wires on the second button.
We fix the battery in the test tube with a glue gun.
We put the adapter on the battery.
After that, we should have two free wires - one from the battery, and the other from the LED. We will connect them at the end. According to the author of the idea, this is very important.
The next step is to take a 10 ml syringe, disassemble it and make a hole on the top of the rod.
With a clerical knife, cut off the upper part of the syringe rod at the site of the recess.
We put the cut piece of the rod in place.
We put a needle on the syringe and fasten it on the top of the test tube with the needle inward with a glue gun.
We connect the remaining wires, not forgetting to insulate everything with electrical tape.
We proceed to the manufacture of a solution for signaling. To make it, we need a glass of water in which we need to dilute a little salt. So water will conduct electricity better. For clarity, the author adds a few drops of green dye to the water, but this is not necessary.
The alarm is completely ready. You can start testing it. To do this, we fix it in an upright position and fill the upper chamber, that is, a syringe, with a solution.
Alarm works according to the following principle.Water in the upper chamber, under the influence of gravity, seeps through the needle into the lower chamber. Accordingly, the lower chamber will begin to gradually fill. When the water reaches the two push buttons, the circuit will close and the LED will light up.
