This blog will keep to a simple theme of my tinkering with electronic and computer related toys, gadgets, projects and the like. I do hope from time to time there is something for someone to find when they are exploring these things for themselves. From an early age, I was always attracted to electronic gadgets an I continue to enjoy myself with my hobby. Unfortunately with a busy life, time becomes short an I can not indulge myself like in the past.
The Evil Mad Scientist Shop has the "Three Fives" Discrete 555 Timer kit designed by Eric Schlaepfer. The "Three Fives" Discrete 555 Timer kit is a replica of the NE555 timer; more over, a full functional transistor-scale replica. The NE555 Timer was designed in 1971 by Hans Camenzind and is featured in IEEE Spectrum, May 2009 article "25 Microchips That Shook the World". The NE555 chip is so popular because it has three operating modes: Monostable, Astable, and Bistable. These three operating modes allow the NE555 chip to be used in a large variety of electronic products just a few are delay timers, alarms, logic clocks, LED and lamp flashers, and power supplies. I enjoyed assembling the "Three Fives" Discrete 555 Timer kit. I also like the fact that the "Three Fives" Discrete 555 Timer can be dropped into a circuit design that requires a 555 Timer chip. I find that it pulls back the veil on the small black microchip and shows the inner workings. The "Three Fives" Discrete 555 Timer kit took about an hour and is very easy to assemble.
The SM-200K kit is to help one get familiar with working with Surface Mount Technology. The SM-200K Decision Maker will answer any question the user asks. When the asked button is pressed, six LEDs are driven on and off; in addition, a buzzer will sound. After a few seconds one LED will remain lite answering ones question. Over a few minutes this LED will dim and then go out. The Theory of operation of the SM-200K is six LEDs are driven by a decimal counter and two oscillators. The decimal counter is driven by one oscillator and the buzzer is driven by the other oscillator.
