Dangerous Prototypes

I got my free MCP2200 breakout PCB well over a month ago in the mail, but the idiot that I am, I mistakenly thought that the breakout was for a SOIC '2200 (I happen to have lots of SOIC '2200s left over from a previous project). Turns out that Mr. Murphy designed the circuit board for a TSSOP '2200 :-/

So I placed an order with Farnell/Element14 (actually Kit-n-Spares for individuals/non-businesses in India) and waited patiently. Apparently some of the parts I ordered were backordered, so the order took forever to come. Having delayed this Free PCB build long enough, I soldered up the PCB as soon as the mailman delivered the shipment. Here are a few pics from the build:

[attachment=2]The bare PCB had some gummy residue left over from the tape that secured it to the inside of the envelope. A little iso-prop on a cloth removed all traces of the mess.


[attachment=1]Most of the parts were in my junk box, scavenged from old electronics. I didn't have all the components in 0805, so I used alternatives - 0603 1k resistors, caps and LEDs.


[attachment=0]The only thing that is a bit of an eyesore is the crystal; I didn't have the surface mount variant (and it wasn't available on Farnell), so I simply used the HC49-3mm that was at hand.


Regardless, the breakout works well, and I have another USB to serial converter!

---

Nice pictures! Also, I did not know that you can stick a through hole crystal onto the surface mount pads like that, I expected the crystal to have signal problems with the legs like that.

Good job with the soldering as well! :)

Great job rohit.
BTW, you can place order from Element14 directly without taking Kits-n-Spares in middle. I order with them directly which gives me more parts range.
The search and add to cart option of main element14 website is very useful(though they have high rates).
Buying from element14 directly requires funds to be transferred to their "Royal bank of Scotland" account, also you can place order by CoD (in both cases shipping charges are 100).

[quote author="hak8or"]I expected the crystal to have signal problems with the legs like that[/quote]I'm tempting Murphy to smite my impudence :-P

[quote author="Arup"]BTW, you can place order from Element14 directly without taking Kits-n-Spares in middle. I order with them directly which gives me more parts range.
The search and add to cart option of main element14 website is very useful(though they have high rates).
Buying from element14 directly requires funds to be transferred to their "Royal bank of Scotland" account, also you can place order by CoD (in both cases shipping charges are 100)[/quote]I had no idea. Thanks! Next order goes directly to E14 :-)

Oh, you can order single piece of MCP2200 from in.rselements at just 119.xRs (tax, delivery to india, etc all included in price). You can pay by debit card there.
EDIT: few days ago I also ordered one MCP2200 at 119.56 Rs  with CoD. Very good experience with them also.

in.rsdelivers.com/product/microchip/mcp2200-i-ss/usb-20-to-serial-uart-converter-w-gpio/6988997.aspx

RS was ridiculously expensive the last time I checked, which, I shall admit, was awfully long ago. Must check them out again. Thanks yet again! :-D

Both RS and E14 sell at global rates which are much more than local rates. For example, a commom transistor BC548 which we all can get in local store at 50p-1Re, costs more than 5Rs.
Few suggesions for passives:
1> Never buy passives from RS. 20-50Rs/0805 resistor. Buy just IC's from them after comparing prices as they have hidden shipping included in every listing price. This time the MCP2200-SS is a good deal.
2> Buy passives from E14. Buy in reel. I do buy 0603 parts from E14 in 100's of quantities. Most are priced at 22p-27p for 100pcs.

I'd recommend you buy 0603/0805 0.1uF/50V caps at 100's of quantities when you place order with E14. You'll never know when the reel finished. 0.1uF required everywhere in power lines for decoupling and stability. For example: http://snpr.cm/ggl3fk.png (http://snpr.cm/ggl3fk.png)

[quote author="arupbsk"]
BTW, you can place order from Element14 directly without taking Kits-n-Spares in middle. I order with them directly which gives me more parts range.
The search and add to cart option of main element14 website is very useful(though they have high rates).
Buying from element14 directly requires funds to be transferred to their "Royal bank of Scotland" account, also you can place order by CoD (in both cases shipping charges are 100).[/quote]

I am a newbie here & a Couple of questions. Location (Trivandrum, Kerala)
1. You say we can directly place order from element14.  Is it really possible as an individual.
When I attempt to register with element14 india, they are asking for a "Sales Tax Registration Number", which is marked mandatory, in their login/registration page.
Can you elaborate on how you managed this hindrance? (or do u really have this !)

2. You say it requires transfer of funds to "Royal Bankof Scotland" account.
Does this mean you cannot use a credit card for purchase?
regards

Hey arup,
where do you source your SMD components from? Also,no local dealer seems to know about 3.3V regulators.Is there some more common equivalent?

Also,just curious,but how much do you spend on electronics,say per month?

I buy my stuff from a couple of places - Delhi (Lajpat Rai Market), Bombay (Lamington Road), Bangalore (SP Road). Here's an address list I posted quite a while back http://www.bits360.com/forum/where-to-g ... t2939.html (http://www.bits360.com/forum/where-to-get-electronic-components-t2939.html). If you prefer buying online in India then there are quite a few 'stores':

http://www.extremeelectronics.co.in

http://probots.co.in (http://probots.co.in)
http://www.nex-robotics.com/ (http://www.nex-robotics.com/)  *****
http://www.triindia.co.in/ (http://www.triindia.co.in/)
http://robokits.co.in/ (http://robokits.co.in/)
http://www.onlinetps.com/ (http://www.onlinetps.com/)  *****
http://nskelectronics.in/ (http://nskelectronics.in/)
http://www.rhydolabz.com (http://www.rhydolabz.com)
http://www.ngesc.com/ (http://www.ngesc.com/)
http://www.allsensor.in (http://www.allsensor.in)  ******
http://www.feemo.in (http://www.feemo.in)  ***** [/list]
I frequent the starred shops. I also regularly buy internationally from:

http://www.iteadstudio.com/

http://www.seeedstudio.com (http://www.seeedstudio.com)
http://www.sureelectronics.net (http://www.sureelectronics.net)[/list]

Local dealers may not know if you ask them for a 3.3v regulator, but they would most certainly know if you ask for the LM1117A-3.3 :-) Tell them the specific part number.

It varies from month to month but I spend roughly INR1000 (~USD20) a month, now that I've got a fair collection of tools. But all of that budgeting goes right out of the window when I need to pick up an oscilloscope or a rework station :-P

My experiences:
http://www.extremeelectronics.co.in (http://www.extremeelectronics.co.in)  shows that it accept credit cards, but actually accept debit cards only (Owner:Avinash)
http://probots.co.in (http://probots.co.in)      I had to pay extra at second bank transfer because (Owner:Pratheek) didn't updated prices in store. No CC
http://www.nex-robotics.com/ (http://www.nex-robotics.com/) *****    No payment repay link/option if payment fails you have to pay by coupons. My package not delivered in 3 weeks then they refunded me. they wasted my 20days project time always making various excuses.
http://www.triindia.co.in/ (http://www.triindia.co.in/)  Not tried yet
http://robokits.co.in/ (http://robokits.co.in/)  Not tried yet
http://www.onlinetps.com/ (http://www.onlinetps.com/) *****  Very good service. Ordered saturday evening 5.30pm and received parcel tuesday.
http://nskelectronics.in/ (http://nskelectronics.in/)    No CC. Prices are outdated just like probots. (Owner:Kiran)
http://www.rhydolabz.com (http://www.rhydolabz.com) Not tried yet
http://www.ngesc.com/ (http://www.ngesc.com/)  ,,
http://www.allsensor.in (http://www.allsensor.in) ******    ,,
http://www.feemo.in (http://www.feemo.in) *****      ,,

@bhishmar,
Use any other's number doesn't matter they dont check if the number belongs to you or not. I have given the sales tax number I saw in a computer's bill. :P

@kmmankad, @bhishmar

For SMD and stuffs that local dealers dont have, and other advanced ICs, (none indian site has any pic24fj for buspirate)
I buy from element14 india.

Yes you have to bank transfer, no CC. You can order with CoD but for CoD dispatch you have to provide waybill which maybe hard to get from sales tax office. For prepaid orders, parcel can be sent without waybill after email confirmation.
They send by Bluedart and Firstflight only ---BEWARE.


My last few month's expense(appx) on electronics:
August: 3000
September: 1000
October: 2000
November: 1300

Whatever I earn online by eBay sales, or through my website, all goes to shopping electronics.

[quote author="arupbsk"]Use any other's number doesn't matter they dont check if the number belongs to you or not. I have given the sales tax number I saw in a computer's bill. :P[/quote]A word of caution though, it is illegal to use someone else's number; it could land you in jail. The the number is used by the government for the purpose of tax collection from businesses. Business transactions are below a certain amount are exempt from taxation, so normally, if you don't buy anything ridiculously expensive on E14 you won't arouse suspicion. But expensive purchases will be taxed to the person whose number you're using. So unless you know the person whose number you're using, I would recommend against this approach.

If a sales tax number is so risky, why shop owners show it in every bill? :P
One more solution: E14 doesn't check the tax number for verification. Use any alphanumeric code
See this screenshot. Any (A-N-Y) fake/invalid number is also accepted.
I've just created an fake account in E14 to prove this. http://snpr.cm/wQA1jI.png (http://snpr.cm/wQA1jI.png)

That is weird, E14 in the USA does not have such things, does INDIA have some requirements for doing online business like the tax form, or is it just something weird that E14 in India does?

Also, this may not be relevant to you as I am based in the USA, but my cost per month for electronics is not THAT high. At first when you start out it is rather expensive depending on how much mistakes you make and how "full featured" you want things. When I started out in electronics, my most expensive purchases were things like a Hbridge ($50 for a nice one), a Basic stamp 2 off ebay ($50), and small cheap tidbits here and there. I also purchased some books which resulted in maybe $100 and a soldering iron as well as solder, which was maybe $30 at most combined. Most of the "important" ic's were from samples (PIC18F's) and buying from digikey.

Later on, the expensises go up depending on the complexity of what you do. After a while you need to start spending more, for example to get an oscilloscope, buying more specific ic's, and getting pcb's fabbed.

The majority of my electronic parts are from junk, believe it or not. Garbage days are like Christmas for me, people throw out lots of fantastic stuff often, and the best parts for me are flat screen tv's and microwaves.

You can use this for more ideas on getting electronic components for free or cheap:
http://electronics.stackexchange.com/qu ... -students/ (http://electronics.stackexchange.com/questions/22040/sources-for-cheap-free-electronics-for-students/)

[quote author="arupbsk"]If a sales tax number is so risky, why shop owners show it in every bill? :P[/quote]Because it is their number. They will not get busted if they print it on a bill. But you certainly will, if you use someone's number. Like I mentioned above, if you buy small quantities and stay below the radar then its no problem. But large purchases are cross checked. If you're planning on making a small prototype run of 100 unit of a device, with components on each costing just INR200 my advice is not to buy with a fake CSTN. Still, its your call. Forewarned is forearmed :-D

[quote author="hak8or"]That is weird, E14 in the USA does not have such things, does INDIA have some requirements for doing online business like the tax form, or is it just something weird that E14 in India does?[/quote]India is trying to clean up its image :-) The number is there to streamline business deals and so that taxes go where they are due :-P The world of e-commerce, credit cards, online access is still new to vast parts of India. Infact, even today when I purchase electronic components, the shopkeeper ask me 'if I want a bill'. With a bill I pay 12.5% more as tax (a part of which the shopkeeper has to pay to the government). In the US everyone has an SSN to which everything is linked - purchases, sales, drivers license. So even though you're not providing E14 with a tax number, you buy by credit card, which is linked to your SSN, which is linked to you.

[quote author="hak8or"]That is weird, E14 in the USA does not have such things[/quote]
Here in Austria (AFAIK it's the same for Germany) both RS Components (Allied Electronics in the US) and Farnell (Newark) do not do business with private customers. According to their terms and conditions they will only accept orders from companies.
There were exceptions to this policy for students last time I checked.

youre _the_ rohit de sa? A fellow electronics enthusiast and BITSG-ian here :)

Yes he's the Rohit who made many projects and wrote on NutsAndBoltsAndFlyingSparks, uploaded nokia 3310 demo on youtube, etc.

I got to know about rohit through a comment in one of my blog's giveaway post.

[quote author="kmmankad "]youre _the_ rohit de sa? A fellow electronics enthusiast and BITSG-ian here :)[/quote]Yes, its a tiny world! I'm getting such a kick right now from this! Thanks for the ego props :-P

[quote author="rohitdesa"]I buy my stuff from a couple of places - ..................
If you prefer buying online in India then there are quite a few 'stores':

http://www.extremeelectronics.co.in

http://probots.co.in (http://probots.co.in)
http://www.nex-robotics.com/ (http://www.nex-robotics.com/)  *****
http://www.triindia.co.in/ (http://www.triindia.co.in/)
http://robokits.co.in/ (http://robokits.co.in/)
http://www.onlinetps.com/ (http://www.onlinetps.com/)  *****
http://nskelectronics.in/ (http://nskelectronics.in/)
http://www.rhydolabz.com (http://www.rhydolabz.com)
http://www.ngesc.com/ (http://www.ngesc.com/)
http://www.allsensor.in  ******
http://www.feemo.in (http://www.feemo.in)  ***** [/list]
I frequent the starred shops. I also regularly buy internationally from:

http://www.iteadstudio.com/

http://www.seeedstudio.com (http://www.seeedstudio.com)
http://www.sureelectronics.net (http://www.sureelectronics.net)[/list]
..........................................................................[/quote]
Hi rohitdesa
I am interested in information about the highlighted site above (allsensor.com). You have given him 5 stars, indicating you regularly buy from him.

If u dont mind pls answer my following queries, & give ur suggestions...
(a) How many times have you bought online from him. ( how long ago in year?)
(b) What is your experience for  -  prompt response for queries,  delivery time,  packaging, product quality etc.

I tried to buy from this site seeing your 5-stars. But my experience is so far very bad.
1. First his site is hopeless, Most products show their price as zero, effectively you cannot proceed with add to shopping cart , and buy these items. It seems risky to attempt atleast.
2. I tried to contact him thru (a) his site -contact, (b) site-enquiry, and (c) by email. All were ignored even after a week.
3. Finally I tried calling him. I found his name was "Vimal raval", He promised to help.  But again end result no response to my queries.
My interest was,  His was the only indian site offering a collection of General Purpose PCB relays- even though price was shown zero!!!  ( I am interested in  48V coil voltage relays industrial quality or any  good quality).  Most sites only give 12V or 6V relays. Even 24V relays are uncommon.
awaiting your reply & suggestions.
* Aplologies for offtopic
rgds

Hi bhishmar! Sorry for the delay in posting. Currently in the throes of end semester exams :-(  Replies to your queries are inline.

Hi rohitdesa
I am interested in information about the highlighted site above (allsensor.com). You have given him 5 stars, indicating you regularly buy from him.
Sorry for the confusion. The stars were only meant as an indicator that I have purchased online from them, not as a quality indicator.

If u dont mind pls answer my following queries, & give ur suggestions...
(a) How many times have you bought online from him. ( how long ago in year?)
(b) What is your experience for - prompt response for queries, delivery time, packaging, product quality etc.
I have bought twice from him in bulk to build kits. Quality-wise his components are good, and his prices are reasonable. Delivery through courier, so it should not take more than a few days to get to you after he has dispatched the goods. He doesn't attend to mails promptly, but you can call him. He's very courteous and accommodating on the phone. Packaging is decent - none of my goods came damaged.

I tried to buy from this site seeing your 5-stars. But my experience is so far very bad.
1. First his site is hopeless, Most products show their price as zero, effectively you cannot proceed with add to shopping cart , and buy these items. It seems risky to attempt atleast.
2. I tried to contact him thru (a) his site -contact, (b) site-enquiry, and (c) by email. All were ignored even after a week.
3. Finally I tried calling him. I found his name was "Vimal raval", He promised to help. But again end result no response to my queries.
His site is actually quite bad, and not updated at all. You do need to call him a couple of times to get him to sit up and take notice. Additionally, he pays more attention to quantity buyers; doesn't really do retail.

My interest was, His was the only indian site offering a collection of General Purpose PCB relays- even though price was shown zero!!! ( I am interested in 48V coil voltage relays industrial quality or any good quality). Most sites only give 12V or 6V relays. Even 24V relays are uncommon.

Nex robotics and OnlineTPS are more responsive to buyers of small quantities. Try them.

I think I have to tryout  element14 then.
I do not know any other indian online site stocking 48V (coil) relays. Certainly OTPS & Nex do not have them.
@rohit: Anyway Thanks for ur time &  comments.

btw anybody else know any indian online site stocking 48V relays.
(other than element14 & rsindia, which are costly, & i think not primarily catering to individuals- asking salestax regn num etc)
rgds bhishmar

Hi Bhishmar,
                  Have you  tried buying directly from Element14? Please share you experience
Regards
Aji

Hi Aji,
    You can buy element14 stuff from http<colon><slash><slash>www<dot>kitsnspares<dot>com<slash>element14 who are their agent in India.
I have used their service and am completely satisfied.

Please do not follow Mr Arup Basak's advice of using someone else's Sales Tax number, it is dangerous and completely illegal.

(Sorry for all the <slash><dot> stuff, this forum apparently does not allow urls in comments.)