Something About Everything

There is a story to be told!

Category: Technology

The love that made a router

It was 1979. Sandra Learner, a young Computational Mathematics graduate from Stanford met Leonard Bosack, in the Stanford computer lab. In a place where nerd culture was in its extreme, Leonard seemed quite different. His clothes were clean, he bathed, and used silverware, she thought. Another girl would have had higher expectations, but that was Stanford, and it was enough for Sandra. She was enchanted.

It was budding love, and something that needed nurturing, and time being spent together. However, Leonard, who managed the computer science department’s computers, and Sandra, who managed the computer system for the Graduate School of Business, worked at opposite ends of Stanford University campus. A campus that was 8000 acres big. They could send e-mails back and forth using the campus Local Area Network (LAN), but their two computers, which ran on different operating systems, could not communicate directly. Using an updated version of an IMP (Interface Message Processor), Leonard, Sandra, and two Stanford staff members ran network cables between the buildings and connected them. They improved the connectivity of the original device so that it worked better with unrelated networks, computer systems, and protocols. Pretty soon, word got out, and other universities began asking for these new, improved devices, which were called Multiprotocol Routers.

The couple realized the commercial potential of the new development and approached Stanford with a proposal to sell the routers commercially. Because Stanford is a nonprofit organization, it could not enter into a commercial venture, and therefore it declined and forbade the group from selling the technology. However, the couple decided to go ahead with the commercialization. Meanwhile the love culminated into the couple marrying in 1980.

A tight budget is always good training ground for an entrepreneur, and the husband-and-wife team put that training to good use when they decided to quit their jobs at the university and commercialize their computer networking invention under the name -

in 1984, a name inspired from the city of San Francisco. Their logo, was based on the Golden Gate Bridge of the city.

They financed their venture by mortgaging their house and persuading friends and relatives to work for deferred pay and sold their first router in 1986.

At first they sold mostly to fellow engineers via Arpanet, an electronic grapevine used by many universities. But they soon realized that not just universities wanted their routers. Even the Proctor & Gamble in San Francisco wanted to talk with the Proctor & Gamble in Des Moines. Within the first year, the company was in danger of going broke. In addition, they had to beat back a demand from Stanford University for $11 million in “license” fees for the right to sell an invention Bosack developed while still on the
Stanford payroll. Stanford eventually settled for about $150,000 plus free routers and support service.

With heavy hearts, the couple approached Donald Valentine, the venture capitalist who funded Apple Computers, for help. They had to surrender the controlling stock in the new-born company. With this, a lot of things changed. Cisco’s initial managers had been a collection of Sandra’s and Leonard’s friends-a 70-year-old retired physicist, for instance, was a plant manager. The new chief executive, John Morgridge replaced them with more experienced hands. Morgridge also built up a direct sales force to woo the corporate accounts. Within a few years, till 1990, the sales had jumped to $300 million. However, Sandra did not get along with Morgridge, and he fired her in 1990, at which point, Leonard, also quit. The two immediately sold their founder shares in Cisco for an estimated $170 million. Like a lot of start-ups, Cisco had its share of growing pains. However, unlike many of them, it was built on an idea strong enough to survive the early turmoil.

P.S.: This story, is a Silicon Valley legend. It is of course based on facts, but the development of any device is not just one person’s handy work. Different parts of the system were built and contributed by different people. This version is highly opposed by Stanford, who alleged that Bosnack copied their design. There is however no indication regarding why they dropped their charges and agreed for a settlement instead. Meanwhile, the legend lives on in the corridors of Cisco and Silicon Valley. Unfortunaley, Leonard and Sandra are now separated.

Hyperlinks not getting saved when you convert word to pdf ?

I had this frustrating experience the other day- I usually use CutePDF writer to convert my word .doc documents to .pdf .

Problem: Suppose you write a direct web address in word i.e. starting with http or www, then the address gets automatically hyper-linked in the word document. When you convert this word file into .pdf using CutePDF, these type of hyperlinks get retained. But now suppose you highlight some text in word, then right click on it, and say – ‘hyperlink’, then this hyperlink will be shown in the word document ; but if you convert the .doc to .pdf, then these type of hyperlinks are not gonna be retained – you will just get a blue underlined text in the PDF file, but when you click on it , nothing happens (the cursor doesn’t turn to a pointer). The same thing happened with many other pdf writers that I downloaded.

Solution:  As much as I fear the sort of monopoly that Google has on the web, must say- some things about it are just too cool. Coming back to the solution, use Google Docs. All you need is a gmail account. Just upload your .doc file. Then edit it if you want in the editor (the word processor has some issues- like the line spacing of ‘single’ in MS Word is approx. equal to ‘double’ in Google Docs. Then click
—> File —> Download File as —> PDF

Cool na ? :-)

On another note, the Indian cricket coach, Gary Kirsten took a page out of Vatsyayana’s famous book yesterday :-P. Pah, i’m sure his ‘have lots of sex’ advice must have had all the Indian cricketer’s blushing…lol…shhhhh… we are Indians, you know  ;-)

Want to Hack My Brain ?

Hackers who commandeer your computer are bad enough. Now scientists worry that someday, they’ll try to take over your brain.

In the past year, researchers have developed technology that makes it possible to use thoughts to operate a computer, maneuver a wheelchair or even use Twitter — all without lifting a finger.

But as neural devices become more complicated, and go wireless, some scientists say the risks of “brain hacking” should be taken seriously. What would happen if a hacker  focused his nefarious energy on neural devices, such as the deep-brain stimulators used to treat Parkinson’s and depression, or electrode systems for controlling prosthetic limbs?

Some might question why anyone would want to hack into someone else’s brain, but the researchers say there’s a precedent for using computers to cause neurological harm. In November 2007 and March 2008, malicious programmers vandalized epilepsy support Web sites by putting up flashing animations, which caused seizures in some photo-sensitive patients. In some cases, patients might even want to hack into their own neural device. Unlike devices to control prosthetic limbs, which still use wires, many deep brain stimulators already rely on wireless signals. Hacking into these devices could enable patients to “self-prescribe” elevated moods or pain relief by increasing the activity of the brain’s reward centers.

History provides plenty of examples of why it’s important to think about security before it becomes a problem. Perhaps the best example is the Internet, which was originally conceived as a research project and didn’t take security into account. Because the Internet was not originally designed with security in mind it is incredibly challenging — if not impossible — to retrofit the existing Internet infrastructure to meet all of today’s security goals.

Neural devices are innovating at an extremely rapid rate and hold tremendous promise for the future. But if we don’t start paying attention to security, we might well find ourselves in five or 10 years saying we’ve made a big mistake. Learn from the past, what say ?

Blackle

All right. This one is gonna be a quickie. Exam times are extremely boring, eh ? Can’t help wanting to post something.

I came across this thing called Blackle. Well- all of you know what Google is. Its like the second brain to all of us. Blackle is nothing but – Black Google. Basically it is a non-profit website powered by Google Custom Search, which aims to save energy by displaying a black background color for search result.

blackle

Some years back, a research suggested, that if Google used a black screen as background instead of a white one, then it would save 750 mega watts/hour per year ! Why so ?

An all white web page uses about 74 watts to display, while an all black page uses only 59 watts. The concept behind Blackle is that computer monitors can be made to consume less energy by displaying darker colors. This concept was first brought to the attention of Heap Media which tried it by utilizing it for screens. A study which tested a variety of CRT and LCD monitors was carried out. Darren Yates, a technology journalist who reviews computer hardware, tested 4 CRT monitors and 23 LCD monitors, and found that the CRT monitors did use more energy displaying a white screen, but less than the calculations made by the idea that inspired Blackle.The LCD monitors tested showed slightly less power use displaying a white screen in the majority of cases, although most of the larger (24-inch) monitors did use slightly less power displaying a black screen.

However, an independent research carried put by Google showed that making the Google homepage black would not reduce energy consumption. To the contrary, on flat-panel monitors (already estimated to be 75% of the market), displaying black may actually increase energy usage.

Well – with contradictory research results, one is really left wondering which one to follow. Is black the new green? Who knows ! At any rate, i found the black screen refreshingly different.

blackle

P.S. I'm not self obsessed. Don't usually Google for myself. :-)

Where did that SMS go ?

Firstly, i think some apologies are called for…Sorry Whiteopal… i’ve been ignoring you a bit, and have had no time to post for a week or so. But i have been really busy- with my minor project, which absolutely refuses to show any signs of being alive :) , and with  making up for all the lost time with a precious person…

Have you ever had that intensely disturbing feeling when a SMS you sent is not delivered ? Or when apparently, it is delivered, but you never got a reply from the other end. If you did, take heart. This happens to all of us. I think the phenomenon of text messaging has created with it a whole new psychology. Instant replies are good, but things stop being so hunky-dory when not getting a reply begins to put you off… Know what? – i made a shocking discovery the other day.

The SMS or text message that you send to people, is not always received by them. I mean, well, that is a bit obvious, you would say- its data and communication , right ? So obviously there may be some loss- but what stunned me was, this may happen even though you get a DELIVERY REPORT. I decided to investigate a bit further into how exactly a SMS is sent, and will tell you now what i learnt… i’ll try to make this discussion as non-technical as possible…

A Mobile Network, or a Cellular Network, is basically a collection of cells…yeah,imagine actual hexagons forming a matrix spread over a particular area. Each cell has a transmission tower at its center. When you move from one cell to another, your mobile automatically changes the tower it is in contact with. Now how this happens is dependent on each network, and we’ll leave that discussion for some other time.

A Cellular Network

A Cellular Network

So even if you are not talking on your cell phone, your phone is constantly sending and receiving information. It is talking to its cell phone tower over a pathway called a control channel. The reason for this chatter is that the cell phone system should know which cell your phone is in, and so that your phone can change cells as you move around. Every so often, your phone and the tower will exchange a packet of data that lets both of them know that everything is OK.

This control channel also provides the pathway for SMS messages. SMS stands for Short Messaging Service. ‘Short’  refers to the maximum size of each page, which is just 160 characters ( Open up your cell phone’s ‘New Message’ option…it’ll show you 450 characters remaining , and the first page will get over when 291 characters are remaining).

But how do SMS messages actually get to your phone? Your mobile telephone network has a element in it called a Short Message Service Center (SMSC) . When a friend sends you an SMS message, the message flows through the SMSC, then to the tower, and the tower sends the message to your phone as a little packet of data on the control channel. In the same way, when you send a message, your phone sends it to the tower on the control channel and it goes from the tower to the SMSC and from there to its destination. The data format consists of the length of the message, the time stamp, the characters and stuff. Now the use of a SMSC has certain advantages. Suppose the person you are sending a message to hasn’t switched on his mobile, or is out of coverage area, then your message gets stored at the SMSC. The storage time alotted to each message is network dependent. It may be as much as 72 hours to something like 12 hours. So when the SMSC gets a signal from the receiver indicating that it is ready to receive the SMS, the SMSC forwards your message.

There are some hitches in this though…due to heavy load of data, messages often get misplaced, or lost by the SMSC. Recall the Diwali, New Year or Holi messages you sent, but which never got delivered. Usually there are 2 types of confirmations that the Networks use to inform the sender whether or not his message has been put through-

  1. Message Submission Reports: After leaving the mobile phone, an SMS message goes to the SMS center. When it reaches the SMSC , the SMS center will send back a message submission report to the mobile phone to inform if the message has been sent. If the mobile phone does not receive the message submission report after a period of time, it concludes that the message submission report has been lost. The mobile phone may then re-send the SMS message to the SMS center.Usually flags are set in this resent message, thus preventing the sending of the same SMS message to the recipient multiple times.  These reports are often indicated by ‘ticks’ in the Outbox.
  2. Message Delivery Reports:After receiving an SMS message, the recipient mobile phone will send back a message delivery report to the SMS center to inform whether there are any errors or failures (eg. unsupported SMS message format, not enough storage space, etc). This process is SUPPOSED to be transparent to the mobile user. If there is no error or failure, the recipient mobile phone sends back a positive delivery report to the SMS center. Otherwise it sends back a negative delivery report to the SMS center.

But again, there are failings in this. Sometimes the receiving mobile sends a false ‘positive delivery report’ , though it hasn’t received the message completely or at all. This is so because on the input side, it gets the message from the SMSC, but for some reasons, it fails to completely interpret the data bytes being received. Despite this, it checks the parity or verification bits in the data, and since they happen to be correct, it feels that it has received all the data. The result being, the SMS sender receives a delivery report, but the receiver doesn’t receive the message !

So now you see….if  you sent your friend a message, and he didn’t reply to it, its quite likely he didn’t get your message at all. The probability of this happening increases exponentially each day- the increase in number of  subscribers far outweighs the capacity of the networks..We are all PROFIT MAKING MACHINES right ? – who gives a shit for any ethics or moral responsibility towards consumers. Actually, i think the cell-cos should really be sued right and left , but i am not sure the existing Indian laws allow us to do that. Yeah, but is you are not from India and reading this, then maybe you should consider doing so.

Take my advice- next time, if you don’t get a reply from a friend you totally expected to hear from, stop feeling shitty and ignored- just pick up the phone and give a ring ! ;-)

Why Firefox 3 beats the hell out of IE 8: Spread Firefox

I’m about to make an embarrassing confession.Back in 2004 , i was under the impression that Internet=IE(Since IE itself had Internet in its name) and vice-versa and there could not be internet connection without IE. How stupid and foolish ! :-P
But Mozilla Firefox changed me. The experience was really amazing, different and i was totally convinced to use Firefox and no other browser henceforth. What really stunned me was Firefox’s robustness and extendability. Its Addon concept was so amazing. It provides millions of additional features ,and the user can choose what he wants, without bloating the whole browser. It thus keeps the size of the core browser under 8MB.

Flashback 2007 : Firefox 2 —> When i first started out,i used Firefox 1.0. Then Mozilla updated it to Firefox 2. However i soon realised that the whole experience was beginning to get pretty sluggish.i don’t quite remember the figures correctly now, but roughly when I opened 5 Firefox windows with an average of 4-5 tabs per window, Firefox was consuming a shocking 500+ MB of memory. Much more shocking was that memory usage was spiraling ,  meaning ; whenever i close a tab or a window it is expected that the memory used is reclaimed back, but that was not happening.

Also those many number of windows and tabs being opened are common for an average user. Fortunately i had 1 GB of RAM but i started feeling, “What about others?” And also there was a nice comparison about IE 7, Opera 9 and FireFox 2 (the latest on which i had got these results) then in many newspapers like Times Of India here. Though in terms of features Firefox was leading, IE 7 was a clear winner in terms of resource consumption.i felt this was a major setback to the growing credentials of Firefox, since most of the users back then did not have machines having more than 512 MB of RAM .

i started Googling on how to improve the efficiency of Firefox 2 ’s trying to find if there were some hacks available. i found lots of complaints from users who had found similar results like me. Many of them said because of these resource constraints they wanted to move out of FireFox and try something else though they were great fans of FireFox. Right then i found a post somewhere from one another fan asking all such desperate souls like me to be patient. He said, Mozilla had learnt its  lesson and in their upcoming release, under development Firefox 3, they were concentrating mainly on memory and resource consumption issues. So i went and saw the release schedule desperately to see when I get my hands on it. It was scheduled to be released on September 2007, but due to the new lesson that Mozilla had learnt they had to do lots and lots and lots of work and rework. So they had indefinitely postponed the release date and had removed the schedule totally from their websites.

Firefox 3 : In November 2007, Slashdot reported the release of FireFox 3 Beta 1. It praised Firefox 3 and its team of developers endlessly. Lessons learnt by Mozilla had started showing up at this point. Apparently Mozilla developers borrowed some memory management tricks from the Free BSD operating system for the Windows and Linux versions of Firefox. (They say memory management on Macs already worked pretty well.) The effect was clear. The browser was much less likely to commandeer too many system resources. And Firefox’s developers worked to make sure that add-ons, notorious memory thieves, don’t cause problems either. They rolled in XPCOM cycle collectors that help prevent extensions from locking up RAM and not giving it back. They also distributed tools to third-party developers that would help them build more abstemious add-ons.

Everything looked great. i simply thought of trying the same empirical test that i had done on FireFox 2.The very same test with 5 windows with an average of 3-5 tabs each now did not consume more than 100MB. i was overwhelmed. All the reports and reviews said Mozilla had brought over several thousands of improvements to its previous versions. The reviews said Mozilla had fixed close to 300 Memory leaks!!! Unbelievable. Accessibility features were improved greatly. The address bar really looked great. The “Suggest URL” feature that appears when you start keying in characters was amazing. It had suddenly become extremely intelligent and suggested exactly what i wanted. Buttons, Icons and Bars had also improved greatly in terms of Accessibility.

Why You should use FireFox:

  1. SECURITY: Firefox 3 protects you from viruses, worms, trojan horses and spyware. If you accidentally access an attack site, you’ll receive a full-sized browser message as a warning.
    Reported Web Forgery

    Reported Web Forgery

    Want to be extra sure about a site’s legitimacy before you make a purchase? Click on a site favicon for an instant identity overview. Another click digs deeper: how many times have you visited? Are your passwords saved? Check up on suspicious sites, avoid Web forgeries and make sure a site is what it claims to be.

  2. Fastest Java Script Rendering EVER ! : Javascripts run 400% faster than Beta 3 and it is the fastest among any browsers. Obsessed with  GMAIL ? It is written largely in AJAX which has nothing but Javascripts to the core. This meant that GMAIL now works 400% faster.
  3. Session Restore : If Firefox unexpectedly closes, you don’t have to spend time recovering data or retracing your steps through the Web. If you’re in the middle of typing an email, you’ll pick up where you left off, even down to the last word you typed. Session Restore instantly brings back your windows and tabs, restoring text you entered and any in-progress downloads.
  4. Simple AND Sweet : The new Firefox looks and feels like home. Think of it as a Firefox who’s really good at making friends. Whether you use Windows Vista, Windows XP, Mac or Linux, the browser seamlessly integrates into your computer’s environment. A native look makes for a flawless interface that never gives you pause.
  5. Smart Download Manager : A pause and resume feature means there’s no need to wait for a download to finish before you disconnect. So, if you’re halfway through the file and it’s time to catch the bus, just pause and pick up downloading when you get home. The resume function also works if your system crashes or is forced to restart.
  6. Tabs: A brilliant way to browse multiple sites at once. Each new site appears as a new tab (not a new window) and can be accessed in one click . Get your sites in order. Simply arrange the order of your tabs by dragging them in one swift move of your mouse.
  7. Multilingual: Firefox speaks your language like no other browser on earth. Over 40 different translations, from French and Chinese to Finnish and Czech.
  8. Customize you Email: In the past you’d click on an email address in a Web site and your computer’s default email application would open up to send a message to the linked address—even if you never email through the program. Now you can choose a Web mail clients (like Hotmail, Gmail or Yahoo! Mail) to launch when you click on that email address.
  9. AND lastly—> IT’S  FREE !!

Impressed ? Don’t take my word for it…look at all these awards …and they are just the latest ones

Download it now,and get rid of that browsing horror-IE !

Already using Firefox ?? Help spread it…

UPDATE : How all the browsers measure up . Source- Techradar.com

Memory Footprint (ten tabs)
Chrome – 141MB
Opera – 113MB
Safari – 163MB
Firefox-91MB
IE8 – 230MB

Sunspider benchmarks (lower numbers are better)-Sunspider JavaScript tests attempt to measure real-world JavaScript performance
Chrome – 1923.0ms
Opera – 4494.8ms
Safari – 4526.6ms
Firefox 3.1 – 1771.4ms
IE8 – 6837.6ms

Memory Footprint (single tab)
Firefox 3.1 – 50MB
IE8 – 59MB
Chrome – 22MB
Opera – 35MB
Safari – 81MB

Cold Launch time
Firefox – 37s
Chrome – 15s
IE8 – n/a

Page load time
Firefox – 8s
Chrome – 11s
IE8 – n/a

How to add RSS Feed to your Blog and Customize the Icon

So you’ve burned an RSS feed to your blog using a website like Feedburner.com. But how do you add an RSS symbol to the sidebar? An RSS feed is no good if blog visitors can’t access the page to sign up for an RSS feed! So you’ll need to add an RSS symbol to the sidebar of your WordPress blog using a text widget.Follow these steps :

  1. Click —->Appearance—>Widgets.
  2. To add an RSS symbol to a WordPress blog, we’ll need to add a “Text” widget. Position the new text widget among your other existing sidebar widgets by dragging it into the spot where you want it.
  3. Open the new, blank text widget that you just created by clicking “edit.”
  4. Copy the HTML code you got from Feedburner—->Publicize—>Chicklet Chooser here.
  5. You’ll see an HTML code, which will be like this :       <a href=”http://feeds2.feedburner.com/wordpress/TGYe&#8221; title=”Subscribe to my feed” rel=”alternate” type=”application/rss+xml”><img src=”http://www.feedburner.com/fb/images/pub/feed-icon32x32.png” alt=”" style=”border:0″/>  </a> <a href=”http://feeds2.feedburner.com/wordpress/TGYe&#8221; title=”Subscribe to my feed” rel=”alternate” type=”application/rss+xml”>Subscribe in a reader</a>
  6. Click —–>Done—->Save changes.
  7. Check out your Blog now.
  8. Now if you want to change the standard icon of the RSS feed,all you have to do is tweak the HTML code above a bit.
  9. To do this,find the image you wanna use as your Feed icon. Remember that it’ll  have to be somewhere on the net. Google for it,you’ll find enough of them .
  10. Just copy the image’s URL and replace the underlined blue part of the HTML code shown in step 5 with the URL.
  11. Suppose your Feed icon is too big,and you want to resize it. Just add  width=”150″ ,height=”150″ in your HTML code like this : <img src=http://dailymobile.se/wp-content/uploads/2008/10/rss_logojpg.png&#8221; alt=”" width=”150″ height=”150″>
  12. Click —->Done—>Save Changes.
  13. Sweet ! :)

Contraption – Tips about Energy Conversions

Robotics is all fine and dandy..i mean you use micro-controllers and motors to do some amazing stuff . But somehow i have always felt that robotics competitions,especially those held in Pune or those that i have seen at various colleges,allow limited latitude for innovation. Suppose it is a race,for which there is a limit on weight and size of your bot. What more can you do,except fit faster,stronger motors (Johnson motors ?) and make your bot light ?

Now Contraption or Rube Goldberg Machine is a different ball game,undoubtedly a more fascinating one,and my First Love ! As you must be knowing,in a contraption,you have to complete a particular task using maximum possible energy conversions ,for example- Kinetic—>Potential, Wind—>Kinetic . This requires a level of perfection and innovation that really appeals to me. i have participated in many contraption competitions until now,and have won in many places too. Today we shall go over how to go about some tricky energy conversions and rake up crucial points.

Kinetic and potential energy conversions are easy enough to achieve-indeed,any form of energy can be broadly classified into either of these 2. eg: Chemical energy can be said to be Potential energy. But in case of contraption,all these are counted as separate.Yes…vibrational,chemical,sound,electric,wind,magnetic,light,rotational etc. are all distinct.

  • Sound Energy—->Electric Energy :The easiest way of going about this is a Clap switch.  A clap switch has a Electret Microphone attached to it,from which the input is obtained. Whenever a loud enough sound a produced (a clap,a book falling) , the switch gets closed,and whatever is attached to the output turns on (like a bulb,a fan,a motor…i’m just giving you ideas). How to make a Clap Switch ? You can check that out here. i could have easily posted the circuit here,but i think due credit must be given to the original author. i have tried the upper circuit a year back,and it works. Here is the pic . Yes,that is cardboard on which i have made the ckt…you really don’t need PCB’s for everything ! If you have problems with the circuit,just get in touch.  Note: Clap switches are sensitive. Even the slightest noise(a foot tapping) may set them off. Always use Clap Switches at beginning of the contraption;later on you don’t care what it does.clap-switch
  • Wind Energy—->Kinetic Energy : You can use a computer fan (the one inside the CPU,over the processor to cool it) for this. You’ll get that for 1 $ or less. You may also use a plastic  lightweight fan,where in the blades are attached to a axle.A string is tied to the axle and wound round and round around it. A weight is attached to the other end of the string.Something sets off the weight and causes it to fall,which pulls the string and the fan rotates. Both of these can be used to push ping-pong balls(table tennis balls).
  • Using Dominos : Well,i say dominos here to specify what i mean,but the ‘domino’ may just be anything…CD cases,books, casette cases,even light wooden blocks cut to size. You can use these innovatively.Simplest use may be just to push something at end of the stack ;but it may also be used to complete a circuit (attach a metal sheet to the last block..let it fall on 2 wires,completing the ckt). Hell,it may even be the weight attached to the Fan i was talking about in the above case !
  • Light energy —-> Electric Energy : yep,you guessed right. Use LDR’s(light dependent resistors) for this.There are just two ways of constructing the voltage divider, with the LDR at the top, or with the LDR at the bottom:

sensor circuits Remember the formula for calculating Vout :


  • Vibrational Energy—-> Kinetic energy : Easy,isn’t it? Just use a mobile phone kept on a slope. There’ll be  different ways of going about this. You may either use one phone to call the one on the slope. For that you’ll need a lever attached to a motor or something to push the ‘call’ button. You may also use timer alarm if your phone has the facility . Note : Only some phones have a vibrator strong enough to set it sliding.Also consider Network Congestion !
  • Chemical Energy—-> Electric Energy : this one’s bit tricky. For starters,it raises unhappy memories of that chemistry exam you barely cleared,doesn’t it ? Secondly,electrochemical cells have a very low output voltage( < 1 V). So you’ll probably need a amplifier at the output.. i’ll just tell you about how to construct a electrochem cell, namely Copper-Zinc . Details of the reaction you can check here. A copper or zinc electrode will be a Cu or Zn plate,nothing less,nothing more. You’ll get it in some chemistry shop for around 2$ . For the salt bridge,use a blotting paper or paper napkin wound in a small roll. Either ends of the roll are dipped in the 2 solutions ( CuSO4 and ZnSO4). Dip the paper in salt solution (salt+water is a good conductor) before using as a salt bridge. You’ll have to think out of the box for this…all liquids conduct,don’t they ;-) ? What if the salt bridge is a wire,and the only work the solutions are doing is completing the ckt  ??? i know i’m wicked ..
  • Chemical energy —-> Heat energy: this is my favourite. Use Glycerine (solution) and KMnO4 -potassium permanganate for the uninitiated (crystal powder). Glycerine+KMnO4—>Heat . Use it to burn some thread.Tip: The reaction is ordinarily a little slow.You don’t want your spectators to get bored waiting for the powder to catch fire,due you ? To quicken the pace,put a drop or 2 of water on the power. Also,use more powder and less Glycerine. CAUTION: the heat produced is intense,and the flame is white. But don’t worry,it is not explosive or anything.
  • Electric energy—->Magnetic energy—->Kinetic Energy : Again a little tricky. You’ll need a electromagnet for this. The problem is,even for a attracting distance of just 1cm ,you’ll need around 2 Amps current. Moreover,you can’t just keep the electromagnet on …above 30secs,it’ll just over heat and the coils around it will melt up ! So you’ll need a mechanism for turning it on,making it do some work(like attracting a iron ball,which will stick to it) ,and turning it off again(it’ll make the iron ball fall). See,i’ve given you a clue for the next step.
  • Electric—->Heat: Solder Irons anyone ?
  • Using Reed Switch : Wikipedia does it the best !
  • Using Bows, See-Saws,Candles…all these are really common,and there’s not much to explain. You’ll also find plenty of stuff on Youtube ( the Japanese or Chinese ta-da-pa-da-pa-di-pi videos will look nice,but won’t be particularly helpful)

Ok. These are videos of my own(there were 4 other friends with me..so lemme say…our own) contraptions. i’m afraid they aren’t particularly enlightening,because i haven’t shot them myself…was too busy ensuring that they work well.Also both have 2 different setups.But go through them if you want more ideas. One is of a stationary setup,the other of a working one.

How to make a PCB – an ExpressPCB Tutorial (Part 2)

Last night,we’d been through making a Schematic(.sch file) for our PCB layout. You can check that out here.

Lets proceed to making the layout itself. At this point,i am assuming that you have a .sch (Schematic) file ready with you.

  1. Fire up ExpressPCB (and not ExpressSCH).
  2. Before we move on to the layout,some basics about PCB’s. A pcb can be of different types-single layered,2 layered,4 layered. A layer basically means that traces(copper connections) will be present on the surface. So a single layered pcb has copper traces only on upper surface,a 2 layered pcb has traces on upper and lower surfaces.
  3. A single layered pcb is advised for most of the applications,whether you are making a board which has a 40 pin IC or anything else. This is bcoz it is cheaper.
  4. However,if you are using RF components of high frequency,then you should probably be using 2 or 4 layered PCB’s .This is becoz there are some issues regarding Power Planes and Ground Planes.
  5. ExpressPCB has 2 options-2 layered or 4 layered.
  6. This tutorial will deal with making 2 layered PCB’s only.
  7. Click —–>File—->New—->2 Layers—->Ok.
  8. Then click —-> File—->Link Schematic to PCB—–> (Select your .sch schematic file)—->ok
  9. 111Now remember this…anything in RED is on the upper surface of your board,while anything in GREEN is on the lower surface. Anything in YELLOW means that it is ‘silk’ or just the name or label of a component.
  10. Keeping everything in either only RED or only GREEN will make your board single layered. If you have traces in both red and green,it will make your board 2 layered.
  11. Rest of the interface is similar to ExpressSCH, only here you have ‘Place Trace’ instead of ‘Place wire’. also there is an additional option of ‘Place Pad’. A ‘pad’ is a hole in your board. It connects the upper layer to lower layer.Components are inserted through holes. Placing pads in your ground and Vcc traces at regular intervals is recommended.
  12. Lets proceed with making a layout for the Voltage regulator whose Schematic we made yesterday.
  13. Click—-> Component Manager—->Semiconductor-TO 92—->Insert Component into PCB22
  14. Then place the capacitors. For capacitors, leading space of 4.5mm is sufficient for disc and electrolytic capacitors. For resistors, keep leading space of 0.5 inch. Note that we aren’t using SMD’s over here,just normal components.33
  15. 55Now double click on each component. Assign EACH of them the SAME PART ID that was assigned in the schematic(.sch). For eg,we named the capacitors C1 and C2. So give them the same names in the layout. You can see i have done that in the above picture.
  16. Click—–>Place a trace—->Then click on one terminal of C1. You will see 2 BLUE marks appearing. One at the C1 terminal and other at the Regulator terminal. BLUE marks indicate that these 2 are to be connected together.44
  17. Connect all terminals together as per the dots shown.66
  18. Now to make some of the traces thicker,double click on each one—>Trace type—>Select the Width
  19. The main Vcc and Ground Trace should be made thicker than the others. Check out the pic below.77 Also ,if you want to draw a trace on the lower surface,select the Green icon with arrows pointing downwards. Check pic below. Don’t forget to place ‘Pads’ at regular intervals in the traces.88
  20. Good. Your nearly done. Re-size the yellow border(outline) of the PCB to make it as small as possible. A SMALLER pcb is a CHEAPER pcb. But take care that its not so small,that you find it difficult to solder components.
  21. Congratulations ! Take a print out of the layout,and give it to some professional PCB maker. It’ll be done real cheap. An AVR development board layout that i made myself cost me only Rs. 80 (less than US 2$).

And lastly,today’s Reason To Smile Winner is …..

How to make a PCB – an ExpressPCB Tutorial (Part 1)

Hello !  Not been able to post for a while,coz i’ve been very busy with my minor project and stuff. Today lets see how we can use a software for making custom made PCB’s (printed circuit boards).

i’m going to concentrate on ExpressPCB ,because its easy and free. You can download it from here. After that,install and start it up. Express PCB has 2 main parts – Express SCH which you will use to draw your circuit diagrams ( if you have used Multisim ,this should be pretty easy)  & Express PCB where in you will make your own PCB layout.

Part 1: Making The Schematic

Since it is difficult to make a layout without having a circuit diagram, constructing a circuit diagram in ExpressSCH is strongly recommended. Follow these steps :

  1. Fire up ExpressSCH.
  2. You will see a ‘Welcome to ExpressPCB …..’ screen. You may go through the quick start guide ,but if you are reading this,that won’t be necessary :-) i’m your turbo start.
  3. Click ‘Ok’
  4. We’ll first need to place some components.Say we want to make a Voltage Regulator circuit.
  5. Lets get familiar with the layout first. Check out the pic below.

    The Interface

    The Interface

  6. Here is the circuit diagram

    Ckt Dig

    Ckt Dig

  7. Click on the ‘component and symbol manager’ ie. the button to which i have shown an arrow pointing to in the pic of the interface.
  8. 21You’ll see the above window. Click    Find–>  Then key in ‘lm7805′. Once you find it,select it and click —>Insert into schematic.
  9. Again click on ‘Component and symbol manager’ and select the 2 capacitors.32
  10. Now to connect the components together,click on  ‘Place a wire’ (the option marked in the above pic). Click once on an end of one component,then another time on an end of another component to connect the them together. Use ‘Insert corner in a wire’ option (directly below  ‘Place wire’ ) to bend the wire into a neater right angle. It doesn’t really matter whether you do this or not.
  11. Please note than ground,Vcc etc. will be found in —>Component and symbol manager—>Library Symbols.43
  12. This was all fine because all components you needed were available in the component manager. If that is not the case,then you have to make your own custom component. Pic below specifies the options you can click to do so.51
  13. Select whatever shape you want .Suppose you want to make a 20 pin IC. So select a rectangle. Then click on ‘Place pin’ option (the 4th of the above marked options).
  14. Go on placing 20 dots in a line. Then click on the ‘Add New line’ option (highlighted in the pic below) to complete the 20 pins. Please NOTE : do not use wires to connect the dots to the rectangle.
  15. 62
  16. Next,select ALL the pins and the rectangle using the ‘Select’ arrow (uppermost option on left). Click  —>Component—-> Group to make component—>Ok     from the menu bar on top.
  17. Now the most important part. Each component must have a unique Label by which it is referred. To assign this,double click on each component and assign a unique ‘Part ID ‘ to each.71
  18. Then  click—->File—-> Check component for Netlist errors. If errors are 0,then save the file. If not,then check your schematic as per the error indicated. Mostly it will be some component naming error(2 components having the same label) To resolve that,assign them unique part id as indicated above.
  19. If you are using a transistor,you are bound to get this error:-9
  20. To resolve it,click on the transistor. Then click —->Component—->Ungroup Component. Now click on each ‘dot’ of the 3 legs of the transistor. Assign a number to each (Part ID). Then select the whole component (dots,lines everything making the transistor). Click  —->Component—->Group to make component.10
  21. Check for Netlist errors again.
  22. Finally our schematic that looks like the pic below.  You file will be saved as      name.sch. Very goood ! Lets move on to making the layout tomorrow…81Good Night for now ! But before i wind up,the Mover and Shaker of the Day- see the video below
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