Thursday...

OK I and others feel that we cant just show you.... You're a student, and this is a learning process.... I and others have schematics we could just send you, but aren't... And we too have some different ways of doing it, there are several.

However, I am gonna give you a hand in the way you approach the problem. (This is how I approached the problem.)In this trade, troubleshooting, and by proxy, design of electrical circuits requires an understanding of the required operation... So lets detail what the circuit needs to do:

  • Either needs, or is limited to 6 lights, and 6 switches.(For now, just draw on a piece of paper what is known. i.e. 6 circles in a row representing the lights.)
  • Only two lights can be on at one time.(Assuming you're entering a tunnel, the first light is on. Mark it with a pencil.)
  • The switch used, changes the state of the light behind you, and the light in front of you.(By this, one can assume that the maximum of two lights that can be on, are going to be grouped together, pencil the next light on.)
  • The light over your head does not change state while operating the switch at that location.(The switch doesn't operate the light over you're head.)
  • Limited to the use of toggle type switches. (3-way, 4-way, Double-pole, or single pole. So for visual referance draw an example of each type of switch at the bottom of the page.)


For simplicity, [Linked Image] assume if it is a DC circuit, every light has a negitive. Or if AC every light has a neutral. Just focus on what the light needs to operate, a positive, or hot to operate. And removal of that positive, or hot to shut it off.

Now "Walk the circuit"

You enter the tunnel, and approch the first light, and switch. The light you are at, and the light in front of you are on.

At the next light, you need to turn the one off behind you, and the one in front of you on.

Look at the examples of available switches, and try each one in the situation. Be creative, because they don't have to be used in the traditional way.

Now, you are on your own....

Mark Heller
"Well - I oughta....." -Jackie Gleason