How do power supplies work?

Intriguing question isn’t it? We all use them whether it’s for computers, tv’s or household appliances. But how do they really work? By definition , the power supply must function by feeding electrical current to an electrical load. The common power supply is called “linear” although the process of transforming DC current to AC current is non-linear.
Take the usual battery for example. It’s a device that has a load of chemical energy and it transforms it to electrical energy. They come in all sorts of sizes and shapes, from miniature ones used for hearing aids to car batteries.
One of the most used power supply is the switched mode power supply. Mostly we use this kind of supply for desktop computers. The AC voltage is filtered thus obtaining AC electrical flow, in order for your computer to function properly! The switching takes place at very high frequencies , usually form 10 khz to 1Mhz , therefore facilitating the use of transformers and capacitors that are cheaper, smaller and lighter than the usual linear ones, more information
One of the “smartest” power supplies are the programmable ones. In my opinion these are a must in every household that intensively uses hi-tech appliances such a as computers , home theatre’s etc., because you can set a certain value for the voltage, that the power supply recognizes and stops every piece of technology it is connected to, before it’s to late! This happens when abnormal high value voltage flow trough the electrical network and burns everything it encounters without any warning , even if all your stuff is turned off at the time.
There are other overload protections such as fuses and circuit breakers. The fuse contains a very small wire that will melt if to much electrical energy will flow trough! The breaker contains a trigger that shuts the circuit down , and it’s much safer if you ask me!


I've heard that 'it's better to have love and lost than to have never loved at all', but have you heard of 'never have loved at all and feeling the loss'?

I think that's what happened. I was apprehensive to describe why Friday was so wretched, but last night as I was trying to sleep, I figured that maybe it should be done. Let me tell you this story.

Last Friday was wretched because I think I got my heart accidentally broken. It was the last thing I expected that could ever happen. See, there's this guy I know and we've been friends for about 7 years now. And that's it. However, on Friday morning before work officially started, and was checking this networking program where I noticed he had changed his status from 'single' to 'in a relationship'.

It was a noisy morning that day, with folks walking in and out. Had it been quiet, I might have heard a snap of something breaking into two. The place where my heart was was numb with pain. I had stopped breathing for a few seconds and when I finally did, the tears just rolled out. I had to run to the bathroom. Could I have been secretly harbouring feelings for this guy that even I wasn't aware of?

I haven't had the chance to talk to him after that (he works far away across miles of ocean) , so I have no idea who the girl is or anything... and as a friend, I'm supposed to be happy for him, but now I find myself wondering what is it that is wrong with me.

I managed to surpress all those thoughts that night by running for 40 minutes until I was so tired, and spent Saturday out with the girls. I stayed away as far as I could from any computer that day. In the end, I thought that it was just a shock, and that I actually did not have any romantic feelings for this guy and all was fine.

But on Sunday, when I went to order a copy of HP and the Deathly Hallows, my mom casually remarked:
Mom: Pity the guy... he got you the previous book. Friends don't do that. Is it more than friends? (she was referring to the fact that he bought for me the 6th HP book two years ago, (books are ridiculously expensive in Malaysia) and that she and my dad got worried because I kept saying he was my friend and they thought that there's something more and one of us were bound to get hurt someday) How could I tell her that he has someone else, and after all this while after learning that fact I realised that I did like him - more than a friend?

Upon hearing what she said, the dull ache came back in a gush. I looked away lest she saw the tears welling in my eyes. I shook my head and said 'no'. Throughout the day, I felt like crying and did so too. Only the fact that I had a mild flu hid the fact that the red eyes and nose was because I cried and not really the flu.

I'm so ridiculously sad, but I find myself unable to tell anyone about this... not my close freinds from uni, or school, or my parents or even my sister. My parents and sister should not know how much this information is hurting me.

It's awful, to think that you realise that you have feeling for someone only after you know that you have no chance to get in the picture. I have the first experience of a broken heart without ever having the feeling of being properly in love. What am I going to do?


I put this post up last night on my other blog

So, there's just a small gap of three months to pass by for GOF to finally play, and for HP and the Deathly Hallows to finally hit the bookstores and send it's legions of fans to tears (more so because it is the final book and there will be no more to wait anticipatedly for, as opposed to Harry finally dying together with Voldermort - my predicted ending)
Anyways, back to the real world... as I was walking down the stairs after work today, I spotted a fairly large butterfly hovering nearby. As expected I kinda ducked to avoid head on collision with the said butterfly. I'm cool with insects, I just don't want them flying near me. I once single handedly caused an old radio to fall off it's place just because a big fat grasshopper decided to hop in to say hi!

When I was roomates with D, she used to say that butterflies brought good luck to those who stumbled upon its path, which is what I did, and surprisingly, the butterfly decided to stalk me. It trailed beside me for about a hundred metres or so until it got bored.
For a moment, I actually thought that someone had transfigured themselves into a butterfly (with brown markings to blend in) to spy on our workplace - security is bloody tight! Hence the reference to HP in the first paragraph. I tossed the idea aside as soon as I left the parking lot.

Coincidently, I met another good luck sign on my way back. There was a rainbow in the sky (at 6:40pm!) where a passing cloud fulfilled its destiny by raining for a bit - judging from the slightly wet road... the sky remained clear as ever, hiding all evidence of having rained,except for the rainbow,that is.

As of now, 9:40pm on this very normal Thursday, nothing of great significance has happened yet.

This part is for today:
Oh boy! Without going into details, I proclaim today to be the wretchedest day ever! Somebody kill me please? And screw that butterfly!

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