Monday, November 22, 2010

WOW- Electronic Skills Using Surface Mount Devices (SMDs)

Nowadays, electronics components are getting smaller and smaller. Devices with the through-hole leads are rarely seen in most consumer electronics. Electronics hobbyists find difficulties in securing some through-hole type because new design packages are widely used. New packages are in a very small size such as the surface-mount devices (SMD). Hobbyists are having too hard to deal working on these small components. For those who did not attempt to work on small electronic component packages such SMDs, SMTs, etc, this video will provide you the first step in developing your electronics skills using SMDs.


Monday, November 15, 2010

WOW- How to control a high-current AC loads by DC circuit (Version2)

This is an improved version from the earlier design posted in this website. The transistor driver (RTL) is replaced by a logic-level transistor logic or DTL. Instead of a resistor at the base, switching diode is used. The purpose of the diode in this design is to prevent the discharge of the capacitor directly to the MCU via GPIO. Discharge will occur when an output of logic LOW voltage is present at the MCU’s GPIO.

The power supply of MCU may be 5volts and it can control a DC circuit with a different power supply. These are circuits having dual power supplies. Ensure both GND of these circuits are connected together. Warning! Don’t connect together the positive side of different power supplies.


There are many variations of the magnetic contactors like the three-phase type. The following illustrations are methods to be used how to interconnect the between the contacts of a magnetic contactor and the load. Magnetic contactors are normally used in AC applications. It may be used for DC applications but check the coil voltage specification before implementation.


-Webscatter, Nov152010

Tuesday, November 9, 2010

WOW- DESIGN REVIEW- Basic Logic Circuit and Technique

In this topic, a brief review of logic circuit and technique is discussed. There are six methods to be demonstrated as follows:
1. Using Logic diagram or combinational circuits
2. Using a TRUTH Table
3. Using Minterms (Boolean Expression)
4. Using Canonical sum or standard SOP
5. Using Simplified SOP or minimum SOP
6. Using Karnaugh map or K-map
Design Problem:
Design a system of a decision-making on buying a T-shirt. The outcome of the decision is TRUE when the three conditions or criteria are fully met. The first criterion is the QUALITY of a T-Shirt. It is TRUE when the QUALITY is excellent. For the other two conditions, COUNTRY OF ORIGIN and SELLING PRICE both must be TRUE. All three conditions are TRUE when the QUALITY is TRUE or both the COUNTRY OF ORIGIN and SELLING PRICE are also TRUE. If all are TRUE, therefore the outcome of decision is to buy the T-shirt.


Friday, November 5, 2010

WOW- How to control a high-current AC loads by DC circuit-2 (using Opto-TRIAC)


This is another way to control high-current AC loads using Opto-TRIAC. The design by principle is similar to the circuit of magnetic relay and contactor counterpart. The use of Opto-TRIAC is also electrically isolated between high current AC loads and DC control. The advantages of Opto-TRIAC are rugged, more electrical isolation and much cheaper than the electro-mechanical type. The disadvantage of Opto-TRIAC is the strict switching schemes and load consideration.

There are a lot of varieties in the design. High end designs are using the more advanced type such as the SSRs or Solid State Relays.

To help you better comprehended on Opto-TRIACs and its design techniques, hobbyists, technicians and engineers must check this following documentation in downloadable PDF format.


WOW- Man’s First Landing In The Moon-A lie or Truth?

In the video embedded above, look at the fall of the camera/lighting units and the interruption of the crew.

Just few days ago, I opened my youtube channel. It gave me a sudden attention. I saw the Greatest Hoax of Science video title. I was keen to open the Apollo and the first man landing on the moon. When I saw the footage of the Apollo moon landing, I was in a great shock. I started terribly to doubt the truth and lies around us. When I was small, my mind fascinated me the wonders of science. Hungry for it, I wanted to explore more by learning science. The breakthrough of science such as the moon landing kept in my mind for years. Surely, all children had the same thoughts. Mankind was proud that man broke the barriers of exploration outside earth. Even setting the first steps in the surface of the moon was the greatest achievement ever the man had. Becoming matured, science stories were imparted to younger ones.

Imagine you are sitting around with children and saw up above the clear night sky. One kid will ask, Uncle, why is the moon shining? Proudly replied, “Child, it is only a reflection of the rays of the sun.” Without contentment the kid asks again, “Had any man stepped on the surface of the moon?” As an older person and knew that there was Apollo landing on the moon. I would quickly say, “Yes, there was!”

How does it feel when you grow up and later realized it was all lies? I am devastated. Surely, children too will be frustrated.

I am looking to a brighter side of this issue. Why man should lie? Or I will change the phrase, “Why superpower countries like US lied? If they committed one greatest lie, what else they are not telling the truth?

The answer lies among us. One of the answer, for sure is to win fame and superiority. Let me give you an example scenario. I am in authority to represent for the government. I am the health minister. I will claim that the Philippine rice has a cancer-causing agent found in every grain. To convince the government and lawmakers, I will present information to look like real facts attested by experts. These experts are in my allegiance. So convincing, lawmakers will pass a bill for a halt of Philippine rice production and full rice importation from outside countries and government will exercise control against possible opposition of the people. This kind of lie is a manipulation of fake information to gain more power and money. If this happens, rice land owners will be forced to sell it to the realtors and converted into commercial lots. Philippine rice prices go down and imported rice goes up. The effects of this lie are tremendous.

How many more lies do people encountered? For thousand of years, people are manipulated by any powerful force. It is the work of evil. All lies are evident in all areas such as religion, science, and history. There are many lies ahead. What everyone can do? Never stop searching for the truth. Discover the truth and show it to everyone. Let everyone know the truth.

Many people are confused between a lie and truth. There are many people lose its faith. There are many people sacrificed their lives to give hope to others who are losing faith. Truth will always prevail and give honor to those who found it.

Be vigilant about the lies and protect the truth…

Source of the video:
“One small step for a man, One giant leap…”

More video source:
“Moon Landing Hoax - Wires Footage”


Thursday, November 4, 2010

WOW- Wheeled Robot from Junks (On-going design)

WOW- Wheeled Robot from Junks (On-going design)

As a leader of a team, I am tasked to lead our R&D team in building a robot. To commence the work, I and a colleague went to the pile of junks in our store room. Gather some items that I can reuse. Mostly, the items are salvaged from unused educational and laboratory trainers. See the following video shown as the result of gathering all the junks. Put all the pieces together. Eureka! It’s a wheeled robot.

The mechanism is ready. One of the missing parts is the control using Embedded System.

Here are the components of the project I planned to build this robot:



WOW-DESIGN TECHNIQUES- Transistor As An Electronic Switch

This section demonstrates a design technique for Transistors used as an electronic switch. For many years as an electronics hobbyist, I used this method in all of my circuit designs. This is the same principle applied by most of the engineers. For the beginners, it is a lot of help developing ideas on how do engineers design electronics circuits. For the engineers, this might give you a review for it.

This circuit is widely seen and very common in many applications especially controlling a certain task electronically.

I am using NPN transistor as an example. The objective of this design is to make the transistor as an electronic switch. In this instance, the “LOAD” component, DC voltage power supply or VCC, and input voltage are given or VIN. To find the actual values and power rating of RC and RB are the goal of the design.

The resistor RC is necessary when the amount of load current is to be only limited below the Collector current rating of any transistor. The resistor RB is calculated to ensure that a very small amount of Base current enough to turn ON the transistor. Turning ON the transistor electronically, it means the transistor is saturated. Saturation of the transistor occurs when a presence of a small current at the Base. It is made also that voltage across Collector and Emitter approximately zero volts and at this point it is acting like a switch closed or Closed circuit. Transistor is cut-off or turn OFF only where there is an absence of voltage applied from the Base.