Wednesday, May 16, 2012

Renewable Energy Technology - Day 2 (May 15,'12)


(I did not post this yesterday! Today it was 3rd day, the points on which I will try and post today.)

Today professor continued on the topic of phasors in 1st session; and covered following:

  • Symmetrical components.
  • Resolving unbalanced phasors (in a 3-ph system) into 3 balanced sets of phasors, namely


  1. positive sequence
  2. negative sequence
  3. zero sequence


  • Representing balanced phasors in terms of unbalanced phasors.
  • Reference Frame Theory

I guess I'll need to go and read some texts and papers to understand these topics properly.

  • Phase Locked Loop (PLL) - an essential component with the help of which we can transfer power from solar power generator system to the grid.

We looked at 1-ph and 3-ph PLL; however 1-ph was covered in more details.
        One liner on PLL!:
           PLL says,"Frequency is latched, and here is the phase difference between them i.e. theta."


  • Need for (or Advantages of) power tracking in PV systems
  • Max Pwr Point (MPP)
  • Grid connected PV systems are more popular than stand-alone systems. Mainly 3 reasons. (may write on this later!)
  • Major Design Parameters 
  • Grid Connected PV Systems in:

           - PAST: Large centralized inverter
           - PRESENT: String Inverter
           - Immediate Future: Micro Inverter (Inverter at module level)

  • Signal Conditioning Systems (connected between PV modules and the Grid to which we want to supply power to)

           - Single stage
           - 2 stage
           - Multi-stage (Eg. PV Module - DC/DC - Hi freq DC/AC - Transformer, Small sized - Rectifier - DC/AC, at line freq of say 50Hz - Grid)


In lab session, the students demonstrated 6 different applications (5 of them on TI boards with micro-controllers)
1. LED Lighting control (This one was the most visually appealing. There were lot of features to control the lighting of 3-color and white high-wattage LED's)
2. Motor control (Controlling two brush less DC motors)
3. Renewable energy demo (I forgot what was demonstrated in this!)
4. DC/DC buck converter ckt (Controlling the Duty cycle. Two converters were there on the board; one with R-load, and other had a small bulb as load, whose intensity was varied by changing the duty cycle, thus controlling the current flowing thru' it.)
5. AC/DC rectifier ckt, used in Telecom applications
6. Characteristics of a small PV board (It behaves as a diode when there is no light)

Monday, May 14, 2012

Renewable Energy Technology - Day 1 (May 14,'12)

Deputy Director Prof. Malik and EE HOD Prof. Abhay Karandikar inaugurated the course.

The program is designed in a smart way, with 2 lecture sessions in morning, and 2 lab sessions in after noon (post lunch)... every day!
We'll have an exam on last day!... to evaluate our understanding. There are also prizes, and not just certificates!

Prof. Vivek Agarwal, course co-ordinator, gave a detailed overview of the course contents, talking briefly over many of the topics to be covered during the course.

In second session, started with the course, and reviewed the concept of PHASORS.

Following are the quick notes that I've summarized in mindmap forms.
Right now not much details are there. The details will be added as the course progresses.








The lab sessions were conducted very nicely by the PhD and masters students in APEL lab, with one main coordinator, and one volunteer for a group of 5. (30 participants, 6 groups).

We're introduced to TI's Piccolo 6000 series microcontroller - its features, and the usage of its components like timers, ADC, PWM generator.

Sunday, May 13, 2012

Renewable Energy Technology (RET) - 5 Day Course at IITB - Blog#0

I'll participate in this course, which is starting tomorrow.
Will post my mind-map notes for each day, on this blog, and also on my site.

Tuesday, May 01, 2012

'PSUs can be the beacon that will show the way to development'

Read a nice article on PSU's - the original purpose to establishing them, their current state, and why they are still needed. Some of the facts were good to know.

Full article is available on eco-times' website, but I thought I'll keep this on my blog for future reading too.
 
(Source: http://economictimes.indiatimes.com/opinion/comments-analysis/psus-can-be-the-beacon-that-will-show-the-way-to-development/articleshow/12944548.cms?curpg=1)
 
-----
 
By Kiran Karnik, Independent Policy & Strategy Analyst

LPG is widely seen as the magic potion that gave India's economy a phenomenal boost. Liberalisation-privatisation-globalisation, or LPG, was welcomed by many as the recipe that not only injected new energy into the slow-growing Indian economic plant, but one that would also be the death knell of the public sector parasites that were inhibiting its development.

Some did die, some are on oxygen, and a few have seen rebirth in a privatised avatar. Many, though, are yet alive. It is in this context - as the new, LPG India turns 21 - that the role of the PSU merits discussion.

Born out of a planned-economy model, underpinned by a Nehruvian-Fabian socialist philosophy, PSUs were conceived as torchbearers of a resurgent India. The economic rationale was that the private sector was unlikely to invest in large, capital-intensive, long-gestation projects with slow returns or high risks.

PSUs were, therefore, set up for steel plants, oil refineries, aircraft manufacture, heavy machinery and such-like; over time, they got into a range of other fields too. PSUs were also intended to secure the 'commanding heights' of the economy, so as to guard against any monopoly, cartelisation or market manipulation by the private sector.

Now that the private sector is able to raise substantial funds, aided by the fact that foreign investment is permitted in most sectors, what - if any - is the raison d'etre for the public sector? The surprising efficiency of PSUs, given the constraints and interference that they have to live with, is generally not recognised, even as the whole government sector has been vilified as being inefficient, slothful and corrupt.

With this background and in new economic scenario, the role of PSUs has obviously to be very different from the days of monopoly. Today, they must act - where they can - as market shapers and influencers. PSUs in hi-tech areas must be leaders in R&D, and invest in long-gestation developmental programmes.

Some of the country's best talent - especially in the engineering domain - is in the PSUs; also, with the exception of the pharmaceuticals sector, the quantity and quality of their R&D is far ahead of that in the private sector. PSUs must leverage this.

Unlike private sector companies, they do not have to worry as much about the day-to-day reactions of the stock market, nor be driven by the QSQT, or quarter se quarter tak, mentality of their private-sector peers. The relative independence from these pressures means that they can afford to focus on the long term.

PSUs should be leaders in environmental issues: conserving energy, water and resources in their processes; recycling waste and water; minimising their carbon footprint and promoting environmental consciousness amongst employees, suppliers and the community.

PSUs should set benchmarks for customer service, transparency, corporate governance and ethics. In sectors where they have a substantial presence, PSUs can ensure that no cartelisation or exploitation of customers takes place, especially when there are demand-supply mismatches.

The airline industry is an example of such trends, and it is disturbing that some time back, there were market rumours of Air India too colluding with private operators to capitalise on temporary seat shortages.

PSUs are commercial undertakings, but the very fact of their being 'public' implies a larger social responsibility. As many instances around the world have shown, public good and commercial viability are not always in conflict. As a matter of fact, the flavour of the day is doing well by doing good.

The roles and responsibilities of PSUs require appropriate managerial frameworks, and these will be impossible without a major revamp of the overall governance paradigm of PSUs. Reform at the board level is the first requirement. PSUs must become truly board-managed organisations, with the government stepping back and giving full power to boards.

At most, the government could retain a say in very large investments entailing debt or raising of new capital, and any fundamental changes in the stated objectives of the PSU. Like any promoter in a private company, the government can nominate board members, but - like listed companies - it must have independent directors and these must be selected by the board, through its nominations committee, rather than nominated by government.

Also, it must be the board - and not the government - that selects and appoints the CEO. The board and professional managers must run the PSU, not the owner or promoter.

One vital lesson of the last half-century is that interference by politicians and bureaucrats is the touch of death for a PSU; this must end. Apart from this, a few simple reforms at the level of the board are all that are required to begin a transformation of PSUs.

This, though, is possible only if there is a change in the mindset of the government. It must recognise that building and strengthening autonomous institutions is a necessary element for a smoothly-functioning society, and a vital part of the economic infrastructure.

It is on this premise that institutions were built in the early years of the Republic. Those that were given - and guarded - autonomy, continue to do well (a few educational institutions, sci-tech organisations, the Election Commission); others that began well have been destroyed through interference.

Sadly, many PSUs, such as Air India and BSNL, are in the latter category. In the new, competitive context with dominant private players threatening to dictate terms in many areas, PSUs are needed more than ever. It is time to reinvigorate them and use them as guardians of public interest and engines of development and economic growth. 


-----
A couple comments by readers of this article. (Source: same as above)
Reader#1
Even in private companies, if there is a junk CEO he will try to have all controls and make things be the way he want them to be. Many CEOs and owners of companies have killed the company for some gain of theirs. Kiran Karnik is asking government to pay money but not have any say. Ask Tata or Premji to do that - that they pay money and not interfere in the running of the company - will it happen ? PSUs are run by public money and politicians are public's representative. If we let managers run everything, what is the guarantee that they wont do something for their personal glorification with least consideration to what happens in the end after they are gone.
 
Reader#2
The author has been very generous, in listing just Air India and BSNL. The majority of PSUs are lacking any autonomy, and are run contrary to business principles. I am just listing two - the oil marketing companies, that are compelled to sell petrol, kerosene, diesel etc. below cost, and are not adequately compensated; and companies like ONGC and OIL, which are forced to pay a cross-subsidy to partly compensate the losses of the oil marketing companies. I can also add the fuel supply agreement that was forced down CIL's throat by a Presidential Directive, even though the Board of CIL, including independent directors, refused to sign such an agreement. These are all traded stocks, where the interest of the minority private shareholder is completely disregarded by the majority government ownership. The so-called independent board members are dummies, being largely retired bureaucrats or "social workers" who are beholden to the government for the perks of office. The temptation of the bureaucrats and politicians to force non-commercial behavior of PSUs under their sphere of influence is very strong. They have no compunctions about killing the PSUs in the process, so long as they get their pound of flesh.

Reader#3
Truely indeed, Rusi Modi once commented that PSU's are like gold mines but unfortunately, the government (the key stakeholder) doesn't know how to mine gold. It is an opportune time to rediscover the worth of the PSUs and nurture them to excel in the resurgent India. The talent of PSUs are sourced from the premier institutions, the employee attrition is at a low and hence the human resources pool of these PSUs should be leveraged effectively to bring transformation.


"Inventing the Future"

(Article published in Economic Times dated Nov 9, 2011)
(Source: http://lite.epaper.timesofindia.com/mobile.aspx?article=yes&pageid=12&edlabel=ETBG&mydateHid=08-11-2011&pubname=&edname=&articleid=Ar01201&format=&publabel=ET)

MarketMind 
Inventing the Future 

ARVIND SINGHAL 


The celebrated New York Times columnist and author Thomas Friedman recently spoke about the many changes happening in the US and,indeed,the world and his advice to governments,businesses and individuals on coping with the same.His advice to job seekers was that they should not any more just try to get a job but make a serious effort to invent one.The implication,perhaps,was that the new world requires a redefinition of skill sets and acquisition of competencies that are valuable to potential employers who can create a job opening for the individual with those currently-relevant skills.


This sagacious advice is quite applicable to entrepreneurs and business leaders too.There are some nearly universal,very powerful emerging themes when it comes to current and potential consumers,and entrepreneurs and business leaders and marketers who can invent new products and / or a new way of doing business itself are the likely winners,while those who are merely looking to retain customers or acquire new ones on yesterdays basis could well join the ranks of losers and have-beens.


In the emerging themes relating to consumers,two stand out.These are to do with increasing poverty of time and,in most markets,increasing gap between demands and availability of financial resources.Consumers across the world,whether in the developed countries or in the developing ones,have to work harder and with lesser infrastructural support either at workplace or at home,putting unprecedented demands on time available to manage responsibilities relating to work,social needs,family needs and personal desires and wants.Further,as the developed economies face stagnant,redundancy-creating or job non-creating growth Friedman very thought-provokingly mentioned that the biggest success stories of the US in recent years,such as Facebook,Google,YouTube,Zynga,Groupon and the like,have created hundreds of billions of dollars in market capitalisation but only a few tens of thousands in jobs coupled with relatively high inflation,and the developing countries,especially India,grapple with very high inflation,consumers across the world are seeing reduced consumption or new goods and services at significantly lower prices.


In the emerging themes relating to the business environment around us,the two that stand out relate to arrival of some new technologies,and the rapid democratisation of and access to multi-functional computing and communication devices for billions of consumers across the world including developing markets.The new technologies relate to further micro-miniaturisation of devices that can perform all kinds of functions,to arrival of devices that can transmit sensations of touch and three dimensions,3D manufacturing and others.As far as new multi-functional communication and computing devices are concerned,the tablet is going to be perhaps the most transformational device invented in the 21st century that can be an extraordinary channel for the billions to communicate,to study and read,to shop and transact,and to be entertained.


There are enough early signs of the dramatic changes in the offing in the next few years transforming complete industries,creating new stars and behemoths while decimating several current iconic businesses.Amazon has recently entered the business of publishing by directly contracting with authors to write for them,potentially threatening or debilitating the established publishing industry and distribution channels for printed books and other printed content.Google-owned YouTube has announced plans to launch 100 entertainment channels by entering into direct contracts with artists and independent content developers on themes covering music,sitcoms,fitness,food,travel and leisure,and many others.The disruptive effect on traditional media companies,and even on manufacturers of conventional entertainment devices (TV sets) may only be a subject of conjecture at this time but is likely to be transformational.Digital commerce is making extraordinary inroads in just about every country,and across every product category of consumption.It is,therefore,no surprise that Amazon is widely expected to become the worlds largest retailer within the next 10-12 years,creating widespread disruption for conventional retail businesses.Similar transformations are expected in sectors as diverse as education (Khan Academy,Academic Earth and paid education sites such as The Great Courses ) and healthcare.


These emerging themes throw up many challenges,but they also offer extraordinary opportunities.To use a term recently used by author Jim Collins,the coming decade will throw up many luck events.The ones who would maximise their returns from such luck events are the ones who can anticipate and accept these disruptive changes,and invent or reinvent their future! 

(The author is chairman of Technopak Advisors)


e-Readers
Almost all the e-readers have audio (music), browser (for internet), mini-USB slot (for connection to PC).
Some also as micro-SD card slot.
Amazon Kindle:
(1) WiFi: $ 139 (Rs. 7000), (2) WiFi + 3G: $189 (Rs. 9500)
- Both 6" screen (diagonally)
- QWERTY keyboard
- Provision to make notes
- 16 levels of grayscale, makes you forget color! (Take it with a pinch of salt!)
Sony
- 'Reader Touch edition'
- $ 230 (Rs. 11,500/-)
- highlight. You can write "on the screen/pdf itself". It will be saved in 'bibliography-summary'.
- dictionary. Select the word, right-click, click on dicitionary.
Onyx - Boox
- 6" touch screen (with stylus).
- pdf: highlight, area-zoom, annotation
- WiFi
- 16 level grayscale
- 4 models. Min cost $280 (Rs. 14,000/-)
- 300gms
- Mem: Int: 512 MB, micro-SD: 32 GB
Indian e-Readers:
1. Wink (by EC Media)
(1) WiFi: Rs. 9000, (2) WiFi + 3G: Rs. 13,750
- Both 6" screen (diagonally)
- Not 'color' yet.
- No Touch screen. QWERTY Keyboard
- Store in Pune: Koregaon Park: Reliance, Reliance Leisures Ltd, CTS No. 15/A 7/15 8/15 9/15,
Koregaon Park Near Taj Blue Diamond, Mobile/Phone No: +91-8108304945
2. Infibeam's Pi2
- 6" screen
- Touchscreen
- WiFi
- Rs. 12,000/- (discounted price. 20% discount on orig price of Rs. 15,000/-)
- Thickness: 11mm
- Weight: 235 gm
- micro-SD card: 32 GB (10k books)
- Internal memory: 2GB
- AC adapter, 4 hrs charging time
- OS: Linux 2.6.28

A User's Review on Sony's 'Reader':
I do wish the Sony had an option to use the digital keyboard for note-taking like you can use it for searching, etc, though. That would be nice (and more legible, as my touchscreen handwriting is atrocious!). The Sony 650 doesn't have wireless or 3G connectivity like some of the other devices out there now. This isn't an issue for me because I browse the internet more on my laptop or phone so it would be pretty redundant for me to have it on my reader as well. When put side by side, the font used on the Kindle seems to be darker with more contrast than the one used on the Sony 650. This seems like it's merely due to the choice of font style, not due to the Sony's screen being inferior in any way. As one reviewer has already mentioned, the sync software available for the reader is terrible. It crashes often and it makes browsing the Sony store very slow and cumbersome. I don't use it if I can possibly help it, not even when I had my 505. I use Calibre for my syncing needs. It syncs beautifully with the Sony reader, especially for tags and collections - all with a few clicks of a button. You can manage your ebook library, convert ebooks, download rss feeds so you can read blogs and news on your reader - it's just an amazingly useful program. One of the main reasons that I sent my Kindle back was because it was nearly impossible to make collections on it in any sensible way. Using Calibre to sync your collections saves time and a lot of headaches
For the first few days I did have a problem with my Sony 650 freezing at random times. It would always come back again when I did a reset, but it was happening quite a lot. I found out that it was due to a large PDF file on my SD card. I used Calibre to convert my PDFs to ePub format and reloaded everything onto my SD card again. Since then, I haven't had a single frozen screen, no matter how fast I try to flick the pages or access the menus. I'm assuming that one of the PDFs was just too large for the reader to handle as-is.




Rose Color Meanings

Rose Color Meanings

Red-----Love, Passion, Respect, Courage

White-----Innocence, Purity, Secrecy

Yellow-----Joy, Friendship

Coral-----Desire

Light Pink-----Grace, Gladness, Joy

Dark Pink-----Thankfulness

Lavender-----Love At First Sight, Enchantment

Orange-----Fascination
 
(Source: http://www.raskys.com/slide.html)

Wednesday, February 01, 2012

Power Sector In India - Article 0 of n!

Hi,
I am keen to understand the Power Sector in India, and have a feeling that my 1st comprehensive blog would be on "Sorry State Of Affairs In Power Sector Of India"!
Have been (only) thinking about it! and have gathered a some news articles from Economic Times, and  Business Standard. But until I stitch the complete sequence of events with my understanding / views, I want to kick-start! Hence this "article 0"...

I'm actually copying the whole text from a webpage of SNP Infra Research Solutions. They have published a report on 'Power Tariffs In India: 2011-12'. Following is intro to the report.


The government needs to take strong measures to help the debt-ridden distribution companies, whose miseries are being compounded by low tariffs and reluctance of banks to finance ­­­­­– given their perception of the sector as unviable. Tariffs are expected to rise once the Central Electricity Regulatory Commission (CERC) approves a hike in the unit price of electricity sold to customers. Many power utilities, including NTPC -- the country's largest power generating company -- have been demanding an increase in power tariffs amidst rising input costs. However, the impending General Elections in 2014 may prove an obstacle to CERC’s move.

There are few states where tariff has been unchanged for the last 4-5 years (unchanged for the last seven years in Tamil Nadu and four years in Rajasthan), whereas loss-reduction demands a 25-30% revision annually. However, some states have been increasing the tariff regularly (such as Maharashtra). In the year so far, 12 states have increased tariffs in the range of 9-34% to ease the burden of distribution companies. Rajasthan, Tamil Nadu, Madhya Pradesh, Uttar Pradesh and Bihar account for 70.6% of the power distribution losses in the country.

India’s state electricity distribution companies (discoms) reported an aggregate loss of around INR 40,000 crore in the year ended March 2010, which is as high as the government’s annual divestment target. The losses are estimated to cross INR 1.16 lakh crore by 2014.

Against this backdrop, SNP Infra Research is launching a report titled “Power Tariffs in India (2011-12). The report will provide an insight into the latest tariffs (2011-12) applicable in each of the states in comparison with 2010-11. It will also capture the percentage change in tariffs.



Thanks!


Wednesday, January 18, 2012

Recipe and Procedure for Daliya (Salty version)

After a long time I prepared some stuff in kitchen today, almost entirely... under the able guidance of my roomie! And liked it very much... so thought would save the recipe for future reference! :)


Recipe and Procedure for Daliya (Salty version):

For 2 persons - in good quantity.

1.
Keep following raw material ready:
- Green peas: quantity according to your liking
- Carrot - cut in thin circular shape. 1 medium sized carrot was good for two of us.
- If you have more veggies, go ahead and add them (in chopped form). These can be lauki (pumpkin), beans, moong (green pulses), etc.
- You don't have to WASH the daliya :)
- Haldi not really needed. I did not add.
- Daliya quantity - two kevis or mini-bowls. ('kevi' is a word in Sindhi language for serving-spoon! :)

2.
Take a pressure cooker
Put 2 Table spoons of cooking oil
Warm it up, on medium to high flame
Add a little 'rai' to it.
(warming is for about a minute.)

3.
Add carrot and green peas to it. 
Mix them.
After about a minute, add daliya to it.
Add water - 4 times the quantity of daliya. In my case, it was 8 kevis or mini-bowls.
Add salt to taste - little less than 1 teaspoon  should be okay.
Mix it well.
Put the lid.

4. Cooking time:
Depending on how much time is available to you:
- we tried: keeping it on minimum flame until 1 whistle and then on medium flame until 2 whistles.
- If you want it quicker: you can go for medium flame all throughout, cook it until 3 whistles.
- Turn off the flame.
- Open the lid after a few minutes. 
- Garnish with finely chopped dhaniya (corriander).
- Serve it and enjoy the delicious daliya with your buddies.

5.  Give me your feedback!  :)


Cheers!

Sunday, April 10, 2011

eReaders' survey (as of May 22, 2011)






(click on the above images, to view them clearly in new page/window)

> Very good website/blog for e-readers' reviews: http://www.the-ebook-reader.com/

e-Readers
Almost all the e-readers have audio (music), browser (for internet), mini-USB slot (for connection to PC).
Some also as micro-SD card slot.

Amazon Kindle-3:
(1) WiFi: $ 139 (Rs. 7000), (2) WiFi + 3G: $189 (Rs. 9500)
- Both 6" screen (diagonally)
- QWERTY keyboard
- Provision to make notes
- 16 levels of grayscale, makes you forget color! (Take it with a pinch of salt!)

Sony 'Reader Daily edition' (PRS950)
- 7" Touch screen (with stylus - but finger/nail also works fine!)
- $ 300 (Rs. 15000/-)
- Highlight. You can write "on the screen/pdf itself". It will be saved in 'bibliography-summary'.
- Dictionary. Select the word, right-click, click on dicitionary.
- Wireless: WiFi only (you can't download using 3G)
- Memory: expandable up to 32 GB

Onyx - Boox 60 (Boox X60)
- 6" Touch screen (with stylus).
- pdf: highlight, area-zoom, annotation
- Wireless: WiFi, CDMA, GPRS, 3G
- 16 level grayscale
- 4 models. Min cost $280 (Rs. 14,000/-)
- 300gms
- Memory: Int: 512 MB, micro-SD: 32 GB

Indian e-Readers:

1. Wink (by EC Media)
(1) WiFi: Rs. 9000, (2) WiFi + 3G: Rs. 13,750
- Both 6" screen (diagonally)
- Not 'color' yet.
- No Touch screen. QWERTY Keyboard
- Stores in Pune:
Croma, Pulse mall - I checked out the 5" (12.7cm) model. Not bad!
Koregaon Park: Reliance, Reliance Leisures Ltd, CTS No. 15/A 7/15 8/15 9/15,
Koregaon Park Near Taj Blue Diamond, Mobile/Phone No: +91-8108304945


2. Infibeam's Pi2
- Screen: 6", Resistive Touch, Black & White 8/16 grayscale, 600 x 800 pixels, 166 dpi, 122 x 91 mm, No backlight
- WiFi. Browser available.
- Rs. 10,000/- (as of Aug'11) + assured gift (which is 10 vouchers of Rs. 1000 each, to buy ONLY BOOKS / eBOOKS)
- Thickness: 11mm
- Weight: 235 gm
- Internal memory: 2GB
- AC adapter, 4 hrs charging time
- OS: Linux 2.6.28
- Memory: Internal memory = 2 GB (expandable up to 32 GB i.e. 10k books; micro-SD card); RAM: 128 MB

My choices:
1. Sony Reader Touch (7")
2. Onyx Boox X60 (6")



A User's Review on Sony's 'Reader' (source: Sony Reader's website):
I do wish the Sony had an option to use the digital keyboard for note-taking like you can use it for searching, etc, though. That would be nice (and more legible, as my touchscreen handwriting is atrocious!). The Sony 650 doesn't have wireless or 3G connectivity like some of the other devices out there now. This isn't an issue for me because I browse the internet more on my laptop or phone so it would be pretty redundant for me to have it on my reader as well. When put side by side, the font used on the Kindle seems to be darker with more contrast than the one used on the Sony 650. This seems like it's merely due to the choice of font style, not due to the Sony's screen being inferior in any way. As one reviewer has already mentioned, the sync software available for the reader is terrible. It crashes often and it makes browsing the Sony store very slow and cumbersome. I don't use it if I can possibly help it, not even when I had my 505. I use Calibre for my syncing needs. It syncs beautifully with the Sony reader, especially for tags and collections - all with a few clicks of a button. You can manage your ebook library, convert ebooks, download rss feeds so you can read blogs and news on your reader - it's just an amazingly useful program. One of the main reasons that I sent my Kindle back was because it was nearly impossible to make collections on it in any sensible way. Using Calibre to sync your collections saves time and a lot of headaches
For the first few days I did have a problem with my Sony 650 freezing at random times. It would always come back again when I did a reset, but it was happening quite a lot. I found out that it was due to a large PDF file on my SD card. I used Calibre to convert my PDFs to ePub format and reloaded everything onto my SD card again. Since then, I haven't had a single frozen screen, no matter how fast I try to flick the pages or access the menus. I'm assuming that one of the PDFs was just too large for the reader to handle as-is.