So just a quick followup from the last project: I only left the battery running for an hour or two, but there was definite visible black oxidation on the nails. (The pennies also changed colour, but I believe this was just them getting "cleaned" by the lemon juice. I should probably look that up.)
Why Are The Lights In Our Hallway So Stupid?
The purpose of project 6 was to build our first "useful circuit", that is, one that has some kind of switching in it. This meant putting in two big fat mechanic toggles. I love these switches! They have a huge chunky THUNK when you flip them and I definitely spent some time just toggling them for the fun of it.
There was lots and lots of reading in this chapter, as well. the first half was talking all about mechanical switches. The kind I'm using for this project are called Single Pole Double Throw ON-ON switches. The phrase "single pole double throw" is also just fun to say. I love these switches!
Anyways, the gist of the matter is that I would be lighting an LED through these switches, and because the switches have two "on" positions but are wired in series, it effectively lets me control the light from either switch. This is the principal behind hallway light switches: If the switches are in the same (or opposite) position, then the light is on, but if they are in the opposite (or same) position, then the light is off. In this way it can be controlled from either end of the hall.
There was lots and lots of reading in this chapter, as well. the first half was talking all about mechanical switches. The kind I'm using for this project are called Single Pole Double Throw ON-ON switches. The phrase "single pole double throw" is also just fun to say. I love these switches!
Anyways, the gist of the matter is that I would be lighting an LED through these switches, and because the switches have two "on" positions but are wired in series, it effectively lets me control the light from either switch. This is the principal behind hallway light switches: If the switches are in the same (or opposite) position, then the light is on, but if they are in the opposite (or same) position, then the light is off. In this way it can be controlled from either end of the hall.
(Hilariously, the hall light in this house does not work this way: Both switches have to be "up" for the light to be on, which basically renders one switch useless: One switch always has to be left in the on position, so that the other can be used to toggle the light on or off.)
Well, the project worked, and I spent more time just flipping those big fat switches, making the light flick on and off. Next project is going to take away these toys and introduce an electronic switch, the relay.
Well, the project worked, and I spent more time just flipping those big fat switches, making the light flick on and off. Next project is going to take away these toys and introduce an electronic switch, the relay.