Solar Lanterns in Household

Since there has hardly been much advancement in the technology used in solar lanterns, manufacturers bank on innovative features based on the applications. Let’s take a quick look at some of the new models in the market: 

- Waterproof outdoor solar lanterns
- Rotatable solar lanterns
— CFL and LED
- Solar lanterns with AC charging facility

Kotak Urja has developed its Sparkler solar lantern with a dual charging system (solar and AC charging options). This LED lantern is light-weight and rugged, with long hours of backup. The lantern is built for safety with a steel grill covering the acrylic and rubberised base to absorb sudden shocks, in case of a fall or the lantern being dropped. Even the electronic circuitry and battery are protected.

BPL Techno Vision Pvt Ltd launched an innovative rechargeable LED based solar lantern lighting—BPL SL1300. This solar lantern is affordable and is equipped with a solar charger and uses BPL’s Q Tech technology, which allows charging even in fluctuating power and has an AC mains charging range from 90 V to 260 V. It also has a dual charging mode—AC charging using Q Tech technology as well as charging through a solar panel. While AC charging takes four hours for five hours of lighting, charging through the solar panel can provide 3.5 hours of light. This model is priced at Rs 1299.

Multi-purpose lanterns with added features: Going by the trends, manufacturers now offer multi-purpose lanterns catering to the specific needs of spread light, focused light, hanging lights or torch lights. Sometimes, all these requirements can be served by one single lantern. Gautam Polymer Group has launched the Solid Solar brand of lanterns, which are multi-purpose, have zero tension light and run for 12-14 hours with a single bright light, whereas with a double bright light they run for 6-7 hours at 3 Wp. With an efficiency of over 80 per cent and luminous performance of 80-100 lumen per watt, this multi-purpose lantern also has an additional mobile charger connection. “Every year, we upgrade our products—earlier we had a switch button on the lanterns; now, we use microcontroller based buttons,” says Shubhra Mohanka, director, Gautam Polymer Group. In April 2012, the company launched the Shivling CFL lantern.

Many of the solar lanterns feature mobile charging sockets (USB type), battery level indicators (as in mobiles) and FM radio options. Kotak Urja has recently filed a patent for one of its products, which apart from carrying all the features just mentioned, also has a projector and fake currency detector.

Solar hawker lights: These solar lanterns are designed for hawkers residing in rural as well as urban areas. They come with a 5 W CFL light, and offer illumination for longer hours than a kerosene lamp. These also come with the mobile charging facility and offer lighting for up to 8 to 10 hours after full charge. These solar lanterns cost between Rs 2500 to Rs 3500, and come with a battery and charge controller housed in a cabinet at the base of the lantern.

Solar lanterns with different light source: CFL and LED bulbs are replacing conventional incandescent bulbs in solar lanterns. Efficiency here is measured in terms of the power consumed—CFL and LED bulbs with lower power ratings produce more light. These bulbs have a longer life than ordinary bulbs. While a standard CFL has a life of about 6000 hours and can spread the light upwards as well, the more advanced LED lights run for almost 50,000 hours.

Rashmi Industries offers a solar lantern with a 7 W CFL, which provides a light output of 52 lumens per watt, equivalent to that of a 40 W (9 lumens per watt ) bulb. This solar lantern has a built-in detachable electronic circuit with an inverter and charge controller. A highly efficient two-step charge controller protects the battery from deep discharge and overcharging.

Another domestic manufacturer, Saur Oorja, offers solar lanterns with fluorescent tubes, LEDs and CFLs, with a battery power ranging from 1.3 Ah to 7 Ah. “These have an automatic lighting up device in case of power failure, and a built-in electrical charger with overcharge protection for safety and long life. These lanterns are available with both amorphous and monocrystalline panels,” informs DK Varshnei, director, Saur Oorja. 




Choices in solar panels: Different types of solar PV panels can be used to power solar lanterns—crystalline and amorphous (thin film). Crystalline panels take up less area than the amorphous panel for the same amount of energy produced. However, crystalline panels do not perform satisfactorily under cloudy or not-so-bright conditions, when compared to amorphous panels. The choice of the panel depends on the location of the lantern as well. Typical ratings of the solar PV panel range between 8 Wp to 10 Wp. 


Different types of batteries: The size or capacity of a solar lantern’s battery is determined by Ah—the greater the Ah of the battery, the longer the bulb can be used. These lanterns usually have a 6 V/4.5 Ah SMF lead acid battery. Nickel metal hydride, nickel cadmium and valve-regulated lead acid (VRLA) batteries are the three commercially available alternatives being used in lanterns. 


BPL Techno Vision has launched a rechargeable LED lantern called Chirag. It uses a 3.3 V and 1600 mAh battery. Unlike the 8-12 hours of charging required by some batteries, this lantern requires only 4 hours of charging and runs for more than 5 hours. 

The backup offered by some of its lanterns is as long as 14 hours. The Jumbo LED and Wonderlite CFL solar lanterns by Kotak Urja not only offer long battery backup but also ensure the lantern is safe. These lanterns are available in both bright mode and night mode (dim light).

How to choose a solar lantern:
Although a solar lantern is a simple device, buyers have a number of doubts while procuring a solar lantern, particularly due to its high price, compared to kerosene lamps. Also, with an array of products available in the market, a buyer might end up buying a low quality product or one that might not be worth the money spent. Thus, a few things should be kept in mind while procuring solar lanterns. 

They are: 

- Location of the user
- Number of hours of functioning
- Choosing the right battery
- The right light source
- Price
- Credibility and reliability
- Protection factors

Cheapest Solar Cooler by Coca Cola for Village

Coca-Cola India is known for its innovative strategies to aid the company's growth. They have often found avenues, that has been left untapped by its competitors or any other brand. This time, the company has decided to open its market in 80,000 Indian villages, that are not blessed with electricity. Out of which, 25,000 have little chance of utilising power in the conventional way. 

The thought of Coca-Cola venturing into this area came, when Atul Singh, president and CEO, Coca Cola, visited rural markets in the summer of 2009, where shops served him warm Coke. When Singh returned, he charged two young Coke engineers, Chandan Samanta and Sunil Gulati, now aged 35 and 40, respectively, with the task of devising a low-cost solution, which came in the form of a solar cooler. 

Three-and-a-half years later, 400 such boxes deployed across many villages are said to be delivering a five-fold increase in sales. The company is confident of making ends meet, as the new business generates more than the cost of the solar cooler. It further plans to distribute 1,000 boxes free to women entrepreneurs in Madhya Pradesh, UP, Himachal Pradesh and some parts of West Bengal by 2013 and the number will go up to 5,000 in the next 3 to 4 years. Moreover, at least 22 countries in the Coke universe have lifted 400 such boxes from Coca-Cola India and are adapting it to their markets.

"It helps when we can decode the consumer's voice, not just for launching new products, but also newer packages, price points' etc," says Singh. "Solar cooler is one such example of an innovation based on local insights and ground realities."

Adds Asim Parekh, vice president - Technical, India and South West Asia, Coca-Cola India, "These (cooler) boxes are bringing first time customers who never tasted our beverages before. The model is helping create a market in areas where Coke was not present at all."  
 

Basic Logic Gates and their Functions

A logic gate is an idealized or physical device implementing a Boolean function, that is, it performs a logical operation on one or more logic inputs and produces a single logic output. Depending on the context, the term may refer to an ideal logic gate, one that has for instance zero rise time and unlimited fan-out, or it may refer to a non-ideal physical device (see Ideal and real op-amps for comparison).

Logic gates are primarily implemented using diodes or transistors acting as electronic switches, but can also be constructed using electromagnetic relays (relay logic), fluidic logic, pneumatic logic, optics, molecules, or even mechanical elements. With amplification, logic gates can be cascaded in the same way that Boolean functions can be composed, allowing the construction of a physical model of all of Boolean logic, and therefore, all of the algorithms and mathematics that can be described with Boolean logic.

In electronics a NOT gate is more commonly called an inverter. The circle on the symbol is called a bubble, and is used in logic diagrams to indicate a logic negation between the external logic state and the internal logic state (1 to 0 or vice versa). On a circuit diagram it must be accompanied by a statement asserting that the positive logic convention or negative logic convention is being used (high voltage level = 1 or high voltage level = 0, respectively). The wedge is used in circuit diagrams to directly indicate an active-low (high voltage level = 0) input or output without requiring a uniform convention throughout the circuit diagram. This is called Direct Polarity Indication. See IEEE Std 91/91A and IEC 60617-12. Both the bubble and the wedge can be used on distinctive-shape and rectangular-shape symbols on circuit diagrams, depending on the logic convention used. On pure logic diagrams, only the bubble is meaningful.

These are the basic gates which are used everywhere now, and universal gates are NAND and Nor gates which can be used for building any kind of circuit.

Nexus 7 tab on sale in india at just Rs19,990

Google’s highly praised Nexus Tablet finally reaches Indian shores, priced at Rs 19,990. Tablet maker Asus confirmed that sale of the tablet would begin, with an entry level Nexus 7 with 16GB storage priced at Rs 19,990.

Though many online retailers have been selling the Nexus 7 in India, the device had not been made officially available in the country by Asus which manufactures the tablet in collaboration with Google.

But the device that would be available in India isn’t the beefed up Android 4.2 version but the older 16GB version that runs Android 4.1. It will be available in Croma outlets across India.

The Nexus 7 has received rave reviews by tech critics across the board for punching well above its relatively cheap pricetag, and was also named ‘gadget of the year’ at London’s T3 Gadget Awards 2012.
Key technical specifications of the tablet include a 7-inch screen with IPS (in-plane switching) screen with a resolution of 1,280×800 pixels.
The tablet is also the first 7-incher to house a 1.3GHz Nvidia Tegra 3 quad-core CPU, which includes a 12-core GPU. It also has a Micro-USB port, 1GB of RAM, and a 1.2-megapixel front camera (no back camera included).

And recently, a comprehensive test carried out by Dr. Raymond Soneira of DisplayMate has said that the display of the Nexus 7 comprehensively outperformed Apple’s newly launched iPad mini which is priced at Rs 27,000 for an entry level device.

And you must also take a look at Reasons why you should stay away from Nexus 7 (Read more about that here)

HTC Desire X Complete Review

HTC Corp. launched a slew of smartphones over the last year, with most of the products aimed at the budget to mid-range category. Only recently did its flagship, HTC One X, see the light of day and even that is soon going to be trumped by the HTC One X+. In the meanwhile, as is the case with every other smartphone manufacturer, HTC is trying to pack in as much as it can in a smartphone while still retaining a mid-range price on its handsets. After all, not everyone is gonna go for the Rs 40,000-plus handset every time it’s upgraded! One of the most recent ‘budget’ launches from the Taiwanese company was the HTC Desire X, an upgrade to the very popular Desire, which was released a couple of years ago. Here’s a look at how worthy an upgrade it is! 

Display

It seems as if in under a year, 4-inch displays adorning smartphones have become the norm. Hence, the screen on the HTC Desire X doesn’t seem massive; it’s just the new ‘normal’. The screen is big enough for you to have your favourite, most-used apps in a 4x4 matrix. Virtual buttons that take you directly to Calls, Emails, Messages and Camera are accessible at the bottom of any homescreen. As is the launch button for all the applications that you have stored or downloaded on to the smartphone. The screen is a Super LCD with a resolution of 480x800 pixels; hence it’s definitely not the most stunning display you would have set eyes on. However, it doesn’t take away from the quintessential smartphone experience at all.

HTC continues its habit of designing distinctive back panels with the Desire X as well. A blue round-edged rim runs around the camera lodged at the back of the smartphone. Against the white soft plastic body, the design is understated yet unique.

Pulling the back panel out was a little more complicated than we’d expect from a seemingly well-designed phone. An awkward wedge-and-pull yanks the panel off to reveal the rather weirdly placed SIM card slot (It is lodged under the camera panel, so you slot it in from one side and push it out of the other to remove it.) You also have a microSD memory card slot next to this, which is thankfully a lot less complicated to manoeuvre.

Messages

The messaging client on the HTC Desire X is pretty intuitive. Well, more than intuitive, it’s a good, quick learner. While at first go, it may not exactly suggest the word you want to type in, once you do, however, it saves your SMS vocabulary and has no trouble predicting it the next time. The keyboard wasn’t cramped either, although personally it’s just so much simpler to type messages in the landscape mode.

HTC Desire X also comes with a ‘Trace keyboard’ option, which has the potential to offer stiff competition to SWYPE. As the name suggests, this virtual keyboard lets you trace your finger across letters to form words, which the handset itself predicts, and quite accurately at that. You can swipe to your left or right across the entire keyboard to access numbers, symbols or special characters.

Camera

As far as pre-shoot settings go, the Camera app on the HTC Desire X offers quite a few. You can tweak the exposure levels, contrast, saturation as well as the sharpness of the image before you click it. Now, these options are accessed through a drop-down menu which takes up a lot of screen space. So, even though HTC offers a live-view of the frame while you adjust the settings, most of my subject was just masked by the in-app menu. Tweaking contrast and saturation levels made the images a little blurry as well as grainy. Without any cosmetic tweaks, the images were better than you’d expect of a regular 5-meg camera.

HTC has thrown in a couple of scene modes that includes an HDR option. The shots taken with the HDF filter on weren’t dramatically different from the ones taken without the filter. The Macro mode seems to work well too except the camera overall results in slightly noisy images.

Whenever I happened to take more than a shot or two of the same subject (with the Continuous Shooting mode on), the camera app automatically prompted me to choose the ‘Best Shot’ after I was done. I could browse through the series of pictures and choose the best one and the smartphone will ask you if it can just delete the rest. I think it’s a smart move, saving a lot of memory space and time which I would have spent later trying to sort through multiples of the same shot.

One feature conspicuous by its absence is a front camera on the HTC Desire X, something that most people have started to take for granted in even lower-end smartphones. The rear camera gives decent results when you capture a video. However, it does not offer high-definition results. Considering most mid-range smartphones now offer 720p recording, I wonder why the HTC Desire X didn’t come with similar capabilities. One good thing about the video recorder is the fact that it starts recording as soon as you click on the video icon (it’s not a camera swap followed by another press to start recording), which saves you from a lot of time fumbling around before you can start shooting. The downside is that you can only adjust one setting during the video shoot; you can choose between having the flash on or off depending on the ambient light. The only other video settings - video quality and record with audio options – have to be chosen before you switch to the video mode.

UI, HTC Sense and Apps

HTC Desire X runs on Android 4.0 and features an HTC Sense 4.1 overlay. HTC Sense retains some of the direct-access icons from the lock screen. So you can drag any of these four icons – Phone, Mail, Messages and Camera – on to HTC’s trademark lock ring and it’ll take you directly to the desired application. Also, HTC still leverages its motion sensor to quieten the volume once you pick the phone off your table, or switch on the speakerphone if you keep it upside down while on a call.

You’ll also find the same ol’ Friend Stream, a social media widget as well as Friend Channel which lets you follow the virtual updates of just one person (stalker much?). SoundHound is packed in to make the most of the stereo powered by Beats Audio. Polaris Office, TuneIn Radio, Teeter, Google Chrome and Adobe Reader are pre-loaded to take care of your productivity and entertainment needs. During the setup, the handset prompts you to log in to your Dropbox account as well. The Dropbox integration gives you about 25GB of free online storage for two years.

One problem with a series of HTC smartphones that we’ve used over time is that you are using an app, and then receive a call and eventually want to end it, the screen doesn’t take you to the in-call menu. You’ll have to swipe it down from the notification bar to end the call.

Battery and performance

The HTC Desire X is powered by a dual-core 1GHz Qualcomm Snapdragon S4 processor, the first one to be featured in HTC phones. Some new launches such as the new Windows phone by HTC are also going to be shipped with the same processor. The handset didn’t give me reason to think it was struggling to execute applications or multitask. I switched between playing ‘Bottle Shoot’ when bored and browsing the latest stories on ‘Pulse’, while streaming music from the 8tracks app and the smartphone handled it all quite well.

On our regular Quadrant Standard benchmarking test, the HTC Desire X scored about 2769 points – not a stellar performance – but managed to shoot above the likes of Motorola Atrix 4G and the Samsung Galaxy Nexus.

The HTC Desire X comes with a 1,650 mAh battery and although the screen is not much of a burner, the handset did manage to last just for more than a working day. I alternated between Wi-Fi and mobile GPRS connectivity and attended to about 10 voice calls, some occasional browsing, gaming and messaging and the indicator was yet to turn red before the end of the day.

Rs 23,499

Love – Feature-packed smartphone, nice gesture-based tweaks, decent battery life

Hate – Average build quality and camera

Even Humanoid Robots Taste Wine

Wine tasting is a skilled job, and it comes more from one's instincts than training. Only that scientists have flipped the bottle -- now, robots can do the job as good as an expert.

NEC System Technologies and Mie University have jointly developed a robot that can recognise various eatables and wines through an electromechanical sommelier.

"There are all kinds of robots out there doing many different things," said Hideo Shimazu, director of the NEC System Technology Research Laboratory and a joint-leader of the robot project. "But we decided to focus on wine because that seemed like a real challenge."

These wine tasting robots can be customized to identify the kinds of wines their owner prefers. The robots can be programmed in a manner that they can recommend new varieties of wine to suit their owner's taste. That's not all, considering the owner's health, the robots can even alert him not to consume a particular drink or food.

The flip side to the coin is the robot can be programmed to accurately identify only a few dozen wines at most. The robots fail to identify the wine once the bottle has been opened and the wine begins to transform chemically.  
 

Top 5 Budget Android Jelly Bean Tablets Under 15k in India

Android 4.1 aka Jelly Bean is the current Android flavour, however, Google has released a revamped 4.2 version of Jelly Bean recently but the new version of Jelly Bean is only available on a couple of new Nexus devices. The operating system is slowly picking pace as Android 2.3 Gingerbread still continues to rule the Android market. At the second spot, we have Android 4.0 Ice Cream Sandwich which is dominating the tablet PC segment. Most of the new Android devices that are available today are either running Android 4.0 or are being upgraded. Jelly Bean is still in its nascent stage and a few devices are running it.

Check out the five budget Android Jelly Bean tablet below:

1)Croma CRXT1075

Price: Rs 5,999

Specs:

 Android 4.1 aka Jelly Bean

Cortex A8 Processor speed at 1 GHz clock speed

Capacitive Touchscreen Screen with 800 x 480 pixels resolution

17.8-cm (7-inch)

2.0 MegaPixel Camera

Video Playback Format: AVI,VOB,MKV,3GP,DAT

3G Network: via USB modem (TATA Photon Modem, EC156, EC1261, MF631) WLAN: 802.11 b/g/n USB: v2.0

Flash Memory: 4 GB,

 512 MB RAM

 Micro SD Expandable Memory Capacity: Up to 32 GB

2) Karbonn Smart Tab 2

Price: Rs 6,699

Specs:

Android v4.0 (Ice Cream Sandwich) OS; Upgradable to v4.1 Jelly Bean

17.8-cm (7-inch) LCD Capacitive Touchscreen

1.2 GHz Processor

2 MP Primary Camera

Wi-Fi Enabled

Expandable Storage Capacity of 32 GB

3) Wicked Leak Wammy Athena 

Price: Rs 13,999

Specs:

Android 4.1 JellyBean

24.6-cm (9.7 -inch) IPS Capacitive Touch Screen

Dual-core 1.5GHz processor

RAM 1GB DDR3 

3G, WIFI, HDMI

Dual Cam 2.0MP+2.0MP (Front & Rear) for video calling

16GB built-in storage (exp to 32GB)

4) Wicked Leak Wammy Desire

Price: Rs 6,499

Specs:

Android 4.1 JellyBean

17.8-cm (7-inch) Capacitive Touch Screen

Dual-core 1.5GHzprocessor

1GB DDR3 RAM 3G

1.3MP front camera

8GB built-in storage (exp to 32GB)

Wifi, HDMI support

21) Zync Z1000

Price: Rs 10,990

Specs:

Android v4.0, upgradable to Android 4.1 Jelly Bean

1.5 GHz Single core ARM Cortex A8 processor

2.0 MP rear and 0.3MP front camera

24.6-cm (9.7-inch) HD capacitive touch screen

Internal Modem- 3G

WiFi- 802.11 b/g/n

7000 mAh battery