Monday, February 1, 2010

Chapter 3 - Exercise 14 Part 2

It's looking like Exercise 14 may take three posts... I'm not quite done with the circuit yet.

As you can see from one of the photos, I had to draw it out to understand it - I'm going to add in a small switch and I needed to figure out where it fit in the circuit. Because I'm using two CR2032 batteries to power this thing (6V), I also needed to put them in series. I think I've got the drawing done correctly...

I started by soldering the two battery holders to the small perf board. I arranged them in such a way that I could solder a small strip of wire between the positive and negative terminals, leaving a positive and negative terminal un-soldered for later. I added in the two capacitors because they share a soldered joint and this would help hold them in place.

Next, I added in R4... it shares a single joint with the positive wire on C1. Then came the 2N6027 PUT. The only tricky part here was trimming down the wires so I didn't create any shorts... some of my joints are spikey little things and I just can't seem to trim them much closer without possibly damaging the soldering I've done. Luckily, I think most of my soldered joints are well clear of one another... my photos should show what I've done (sorry for that one blurry one)...

Next, I've got to drill a hole in the side of my project box where I'll mount the switch. I thought about putting it on top but there's not a lot of room for the lower portion with the terminal posts... plus I like the look of it on the side. Flip it up, the circuit will turn on... flip it down, the circuit turns off. The LED will be the only thing mounted in the top, and I've got to drill a hole for that, too... probably tonight or tomorrow. After drilling the holes, I want to paint the box white, maybe add a mushy Valentine's Day message somewhere on the contraption, and I'll add this to the stuff for my wife on V-Day. Silly... cheap... turns on, turns off... worth a few Husband Points.


  1. You mean you couldn't find a pink, heart-shaped project box? Deduct 10 husband points for that!

  2. Actually, I found a small heartshape box made of cardboard and another ceramic one... wasn't sure how flimsy or tough they would be to work with...

    Hang with me - I'm not done yet :) I always prefer to make something myself as opposed to buying... so a little spray paint and some creative license, and I think I'll have something fun to deliver. Please see my next post... up in about 10 minutes.