Skip to content

Fun With Snap Circuits 2: I’d Rather Fight Than Switch.

When you retire, you switch bosses – from the one who hired you to the one who married you.  ~Gene Perret

When you enter a dark room, what is the first thing you usually do? Look for a light switch. You flip the switch on and let there be light.

A switch is probably the simplest electronic device. When the switch is off, the circuit is open and no electricity can flow. In the water pipe analogy recall the tank of water with a pipe connected at the bottom. To stop the water from running out of the tank, we can add a valve–more commonly called a faucet. When the valve is off, no water can flow through the pipe.

When the switch (valve or faucet) is off water cannot drain out of the tank.

Conversely, when the valve is on, water can drain out of the tank and flow through the pipe.

When the switch (valve or faucet) is on, water can drain out of the tank and flow through the pipe.

The switches that you will usually use with  Snap Circtuits are the pushbutton switch and the Single Pole Single Throw switch.

The pushbutton switch, or “Press Switch” as it is labeled in Snap Circuits, is a simple button that you push to switch it on. The switch will remain on for as long as you hold the button down. When you release the button it will switch off.

The Snap Circuits Press Switch will remain on for as long as you hold the button down and will switch off when you release the button (Source: Elenco Electronics, Inc.)

When the Press Switch is in the off position, the circuit is open. In the water pipe analogy, no water can drain out of the tank and flow through the pipe.

In the off position no current can flow through the circuit, in the on position, current can flow through the circuit.

When the Press Switch is in the on position, the circuit is closed. In the water pipe analogy, water can drain out of the tank and flow through the pipe.

The Single Pole Single Throw switch, or “Slide Switch” as it is labeled in Snap Circuits, is similar to a light switch in your home that you flip to switch it on. The switch will remain on until you slide the switch to the off position.

The Snap Circuits Slide Switch is similar to a light switch in your home.

When the Slide Switch is in the off position, the circuit is open. In the water pipe analogy, no water can drain out of the tank and flow through the pipe.

In the off position no current can flow through the circuit, in the on position, current can flow through the circuit.

When the Slide Switch is in the on position, the circuit is closed. In the water pipe analogy, water can drain out of the tank and flow through the pipe.

Now you know what a switch does, how some of the Snap Circuits switches work, and what their schematic symbols look like.

Advertisements

Fun with Snap Circuits 1: “Scotty, I need more power!”

“Power tends to corrupt, and absolute power corrupts absolutely. Great men are almost always bad men.”  –John Emerich Edward Dalberg Acton

Nearly all of your Snap Circuits projects will need power and usually in the form of Direct Current (DC). So, we’ll need batteries.  Batteries are used to store energy. We can think of a battery as a water tank. The tank will hold water until we can drain the water out of the tank. To drain the water from the tank we can connect a pipe at the bottom of the tank. This will allow the water to flow through the pipe and we can use the water flowing through the pipe to do useful work. Keep in mind, of course, that what is flowing is a current of electrons rather than a current of water, but the water pipe analogy is often used to help people understand electronic circuits.

Imagine a battery as being a tank full of water. The tank will hold the water until we connect a pipe at the bottom of the tank that will allow the water to flow through the pipe to do useful work. (Source: http://www.appropedia.org/Electricity_basics)

The above graphic is the simplest way to think about how a battery puts energy into a circuit, but there are other ways to imagine an electronic circuit. I found these two Quick time movies that can also help you to visualize the flow of current through a circuit. In the in the first movie we see a hamster running in its exercise wheel. The axle of the exercise wheel is connected to a waterbucket wheel. As the water bucket wheel turns each bucket scoops up water from the bottom trough and raises it up to the top trough where the water from each bucket is dumped out. In the second movie, the water in the top trough flows to a drainpipe that drains into the bottom trough. The water flows from the drain pipe back to the waterbucket wheel to be scooped up and raised to the top trough again.


Click here to view the first quicktime movie

Click here to view the second quicktime movie

You can think of a battery as a filled tank of water or a hamster driven waterbucket wheel or you may have thought of another anaology–whatever is easiest for you to visualize a battery a putting energy into an electronic circuit. Indeed, in the Snap Circuits manuals, you may see a  water pump used as an anaology for a battery.

Water pump analogy for battery (Source: http://manuals.elenco.com/manuals/scbe75.pdf)

In some of the Snap Circuits manuals you may see a complete electronic circuit pictured as a water pipe analogy:

Complete electronic circuit pictured as water pipe analogy. (Source: http://manuals.elenco.com/manuals/scbe75.pdf)

Occasionally you might see the piston analogy used for a battery in Snap Circuits manuals and sometimes online too:

The piston pushes the water through the pipe.

Now that we’ve beaten the water pipe analogy to death we’ll take a look at the electronic symbol  for a battery, and as I said in the introductory post, the cool thing about Snap Circuits is that the electronic schematic symbol for each electronic component is printed on the plastic case. Here is an example of a battery holder:

Snap Circuits battery holder has the electronic schematic symbol for the battery printed on the plastic case. (source: http://manuals.elenco.com/manuals/scbe75.pdf).

Now you know what a battery does and what it’s electronic schematic symbol looks like.

Here’s a video by Areil Churi from Sparkle Labs that may help you understand batteries and electrical pressure:

Electrical Pressure from Sparkle Labs on Vimeo.

Welcome To Fun With Snap Circuits!

Snap Circuits by Elenco is an educational toy that teaches folks about electronics with solderless snap-together electronic components. Each electronic component has the electronic schematic symbol and a label printed onto its plastic case that is color coded for easy identification. They snap together with what appear to be ordinary clothing snaps—hence the name Snap Circuits. The components also snap onto a 10 X 10 plastic base grid, which is analogous to a solderless breadboard.

There are several Snap Circuits kits that range from a few simple circuits to the largest kit that includes 750 electronic projects. All the kits include manuals printed in color with easy to follow diagrams to assemble the projects. The illustrations for each project look almost exactly like what the components will look on the base grid when finished. Because the electronic symbol is printed on each electronic component, once the project is completed,  it will look almost exactly like a printed electronic schematic!

Example of Snap Circuits project from Snap Circuits Micro kit. (Courtesy Elenco Electronics, Inc.)