Invention Lab — Powered by RadioShack®

I am now 40 years old, working as on optical and electrical engineer but I started with electronics when I was 10 years old. It began with a Radio Shack 150-in-1 kit from a garage sale. I was so enthralled by it that the woman selling it gave it to me for free.

I first studied electronics formally in high school. I was in my sophmore year and I was building a 12V power supply from parts I bought at RadioShack. I was nearly done with the project when it was “bath time”. I took my shower, put on my pajamas and ran back down to the garage to finish the power supply.

I wanted to make sure the ripple was low so I hooked the output up to my grandfather’s old oscilloscope. Now this was in the mid-80s so I am talking REALLY old here. My grandfather was one of the first TV repairmen in southern Connecticut and this was his oscilloscope from the early part of the 20th century. Back in those days plugs were NOT polarized. Also, one of the prongs on the power plug was hard wired to the case. Well, when I plugged it in I must have oriented the plug so that the case was tied to the hot part of the 120V outlet. Of course, our garage had a nice, grounded, cement floor and my feet were still wet from my shower. When I grabbed the oscilloscope I immediately started hopping up and down from the current flowing through my wet feet to the garage floor. From that day forward I was always very careful to be aware of what was wired to hot and what was wired to neutral!

I had just barley started working with circuits and somehow i found the LM368 IC and started on a simple portable guitar amp. the circuit was simple but included volume, gain, and a switch with led. I put it all into a box with a 4ohm 5 watt speaker and i am not modifying it to put a wall adapter with 12 volt regulator.

I just recently uploaded an Assembly and Application Manual for a Logic Probe kit I’ve devloped to my website . The manual shows with color pictures and illustrations how to assemble the kit you parts from Radio Shack. What make’s this kit unique is instead of using the traditional LED for displaying binary data ( 1-ON, 0-OFF), my kit shows the letter “L” for logic Lo and “H” for logic Hi using a MAN 72 Seven Segment Display. This kit can be used to troubleshoot and analyze digital & microcontroller circuits as well as LEGO NXT machine applications. I’m working on cost and packaging for the kit and will post it at my blog when. The manual is a free download so go check it out.

Regards

Don W.