Electronic Schematics Diagram-The Four Commonly Asked QuestionsWritten by Jestine Yong
I came across quite a number of questions about electronic circuit schematics diagram. Most of question asked are: a) Do we really need a schematic diagram in order to repair any electronic equipment? b) Will schematic diagram help us to repair faster? c) At where we can get a particular schematic diagram? d) How to read schematic diagram ? Well, answers is as below:
a)-Theoretically yes, practically not necessary, it all depends on how good you are in electronic repair knowledge. For a beginner it is a 'must' for you to understand about schematic diagram, as you gradually gained more knowledge you will automatically depends less on schematic diagram. You will definitely need a schematic diagram when you come across a new designed or technology. For example, when comes to crt monitor repair i seldom see schematic because i already understood most of circuitry and section in a crt monitor. The new technology such as lcd or tft monitor makes me have to temporarily relies on schematic diagram. As my knowledge of lcd monitor repair grows, i will gradually depends less on schematics. May be my situation is different from yours because i'm concentrating only on one type of equipment. I've seen quite a lot of repairers in my country that repair many types of equipment such as tv, video, vcd, dvd, amplifier, hi-fi, fax, laser printer, microwave and so forth. Most probably they need schematic diagram to keep them up to date on each of equipment technology.
b) If you have a particular schematic diagram for that particular equipment, your troubleshooting time can be reduced to half! Unfortunenately many manufacturer do not release their equipment's schematic diagram. If you depends on too much of schematic you will be stuck on how to repair that particular equipment. Why with schematic diagram you can repair any equipment faster? Because a schematic diagram shown you all part list, waveform, voltages, explanation how that particular equipment work, block diagram, schematic design, component's part number, electrical schematics symbols, substitution, modification (if have) and electronic schematic symbols and etc. Assuming you have a power supply section blown and you could not recognize component part number, but with schematic you will be able to find exact part number and finally repaired equipment.
Digital SLR Camera versus a Compact Digital Camera. Written by Virginia Wong
Digital Single Lens Reflex (SLR) cameras are excellent cameras that produce clearer, sharper and more colourful images than most point and shoot digital cameras available. With prices falling rapidly, they are now more affordable then ever. With price gap between an entry model digital SLR camera and most expensive compact digital camera narrowing; question is… do I spend extra money and get a Digital SLR camera? or save a few hundred dollars and purchase best digital compact camera. Well, it really depends on your budget; however if you do spend extra money, here's what you get: In addition to price falls in Digital SLR models, performance on these cameras has increased year on year with latest Digital SLR cameras being quicker and faster than ever before. They have improved to such an extent that power up or start-up time is near instantaneous with virtually no lag time. “Lag time is time between you pressing shutter release button and camera actually taking shot”. This delay can vary quite a bit between different camera models and it is one of biggest drawbacks compared to a compact digital camera. The latest digital SLR cameras have virtually no lag times and react in same way as conventional film cameras, even in burst mode. Compact digital cameras are catching up; however difference is still significant. A lag time of ~0.5 seconds can result in you missing heartbeat of moment and hence that potential great picture. Digital SLR camera also has a larger sensor versus a smaller sensor in a compact digital camera. This equates to higher sensitivity and less noise and results in camera taking clearer pictures in low light. (They also have better autofocus speed in low light as well). A measure of sensitivity in a digital camera is ISO and a typical ISO range for a Digital SLR camera varies from ISO 100 – 1600 with latter being more sensitive. The ISO range for a compact digital camera varies from ISO 50 – 400. In summary, higher ISO rating, greater sensitivity and better photo can be taken in low light.