Friday, March 5, 2010

Chapter 4 - Exercise 20 Relay

I decided to cut open the dead relay I had purchased a while back (dead because any voltage applied to it doesn't seem to make the relay click)...

The top-down view is the one that I can best explain. See that white piece of plastic shaped like a T? From the picture's POV, pushing on the top arm of the relay pushes against the piece of plastic and that, in turn, pushes on the second relay arm (on the bottom). But it doesn't work in both directions... pushing on the bottom arm does not move the plastic and the top arm stays where it is... so I've just got to think this through and figure out how this relay works with respect to the circuit I'm building.

Chime in here, folks... it's been a long week and my brain's not firing on all cylinders. Anyone care to take a stab at explaining how this little relay works?

And by the way... the description for this relay is dual coil... is the 2nd coil inside the outer one?


  1. Are there supposed to be pictures with this post? I don't see any . . .

  2. Yep - there are two photos - and I'm seeing both of them.

    Did you get your notebook yet?

  3. Whoops. My bad. My AdBlock was blocking them. I see them now. No idea how it works though.

    I got the notebook yesterday. Thanks a lot. The reference section looks particularly useful.