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Electronics => Beginners => Topic started by: rstor22 on August 11, 2016, 11:57:19 pm

Title: Where to purchase cheap components to have a basic stock for prototyping
Post by: rstor22 on August 11, 2016, 11:57:19 pm
When looking to purchase a basic stock of components such as E12/E24 resistors, E3/E6 capacitors (ceramic/electrolytic), LEDs, ICs, voltage regulators, etc to have a basic stock for prototyping/personal projects, how do vendors from eBay (specifically those located in China) compare to components ordered from places like:

http://www.taydaelectronics.com/ (http://www.taydaelectronics.com/)
http://www.dipmicro.ca (http://www.dipmicro.ca)
http://www.futurlec.com (http://www.futurlec.com)

Would the quality be considered the same?

Does anyone see any issues with purchasing a basic stock of components from any of the above vendors or eBay sellers located in China (again, components will be used for prototyping/personal projects)?
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: JoeN on August 12, 2016, 12:34:54 am
I've purchased from both Tayda and Futurlec and have had good experiences with both, especially Tayda.  Tayda ships from the US if you buy on the US website.  For us in the US it seems to come in about 5 days which is fast considering they charge very little for shipping.  Futurlec comes from  the east and takes longer.  They used to be very good at LED matrices which I quite like but I haven't bought from them in a while.   Tayda is one of my favorite vendors.
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: Audioguru on August 12, 2016, 12:41:07 am
I don't buy cheap Chinese fake and factory reject parts from ebay. Instead I buy genuine high quality American and European parts from Digikey and Newark. They have offices in Canada and maybe have warehouses here too so you get the parts quickly without customs clearance and duty.
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: JoeN on August 12, 2016, 03:01:27 am
I don't buy cheap Chinese fake and factory reject parts from ebay. Instead I buy genuine high quality American and European parts from Digikey and Newark. They have offices in Canada and maybe have warehouses here too so you get the parts quickly without customs clearance and duty.

I agree as far as proprietary single-source parts go, sometimes the part is actually cheaper at Digikey, Mouser, Newark, than eBay sellers (use http://www.findchips.com (http://www.findchips.com) to find out).  Very few of the cheap Chinese guys have that stuff other than popular microcontrollers.  I don't think I would agree on resistor and capacitor sets and LEDs and things of that sort.  LED matrices and discrete LEDs are many times more expensive at Digikey and I don't see the advantage to using them for hobby projects.  You know if an LED works or not or if a resistor or capacitor is the right value, it isn't like they can screw you over with a rejected or relabeled opamp.  Also, just try buying solder at Digikey.  A pound of Kester is like $50 whereas the same roll will be $22 at all-spec.  So it's good to know alternate places to buy when it makes sense like Amazon, All-Spec, or even the local Fry's if you have it which is competitive on chemicals (since you don't pay shipping which can be enormous for chemicals).
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: Brumby on August 12, 2016, 03:22:49 am
Cheap Chinese sources can have issues that you won't get with reputable suppliers.

A little while ago I picked up a TH resistor pack because it was stupidly cheap.  There was one value missing from the pack which was mildly annoying, but they were offered as 1% tolerance.  A quick sample indicated they were more like +0% -2% than +/- 1%.

Didn't really matter for what I needed at the time ... 5% would have been good enough.
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: jeroen79 on August 12, 2016, 06:35:22 am
You have to ask yourself why certain suppliers can deliver for much lower prices.
Did they cut out the middle man in europe?
Did they invent a more efficient process?
Are they selling second rate projects?
Are they scamming you?

Then ask yourself what you need.
Do you need reliable parts that something critical will depend on?
Do you need decent parts that have a good price/quality ratio?
Do you need a lot of cheap parts for experimenting?
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: JoeN on August 12, 2016, 08:31:44 am
Then ask yourself what you need.
Do you need reliable parts that something critical will depend on?
Do you need decent parts that have a good price/quality ratio?
Do you need a lot of cheap parts for experimenting?

That's sort of my point.  The people here asking amateur questions (like me ) are not flying their project in space or putting it down a bore hole.  Mostly it's all a bunch of blinkenlights, some sensors, etc.  If you need a bunch of resistors and LEDs for a big blinkenlight display, I say buy them on eBay and save yourself a small mint.
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: setq on August 12, 2016, 09:35:50 am
I vote for buying a small quantity of quality parts when you're starting out and buying on demand. I had a couple of false starts that were caused by buying crap parts and equipment.

Some of the component packs from eBay and Aliexpress are dire. One of my favourite cock ups was buying 1 ohm resistors and finding that they were actually between 0 and 5 ohms. Big problem as they were for current sampling. Bought the same things from RS branded Vishay and they were all 1ohm +/-1% on the dot.

I stick to branded parts from RS here in the UK now and this generally works first tim and I probably spend less than preemptively stocking stuff I'll never use.
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: all_repair on August 12, 2016, 10:22:58 am
It is a good idea to stock jelly beans and build up your stock on prototyping.  But try not to buy them as a sepecial purchase by itself.  Prepare your shopping list, and use them as filler to get free shipping when you are actually getting something you really need.
In no time, you shall have yours almost for amost free considering the shipping fee you might have paid.
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: Audioguru on August 12, 2016, 12:53:15 pm
Cheap? Why? High quality electronic parts are not expensive (like jelly beans) so buy name-brand from a local real electronic parts distributor.

My cheap Chinese solar garden lights have LEDs with exactly the same brightness, color and beam width. Then they are high quality? No. They use iron leads that rust away in a couple of months outdoors. I replace the LEDs with high quality inexpensive Luxeon LEDs by Philips.
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: rstor22 on August 12, 2016, 03:18:54 pm
I don't buy cheap Chinese fake and factory reject parts from ebay. Instead I buy genuine high quality American and European parts from Digikey and Newark. They have offices in Canada and maybe have warehouses here too so you get the parts quickly without customs clearance and duty.

I agree as far as proprietary single-source parts go, sometimes the part is actually cheaper at Digikey, Mouser, Newark, than eBay sellers (use http://www.findchips.com (http://www.findchips.com) to find out).  Very few of the cheap Chinese guys have that stuff other than popular microcontrollers.  I don't think I would agree on resistor and capacitor sets and LEDs and things of that sort.  LED matrices and discrete LEDs are many times more expensive at Digikey and I don't see the advantage to using them for hobby projects.  You know if an LED works or not or if a resistor or capacitor is the right value, it isn't like they can screw you over with a rejected or relabeled opamp.

I also purchase from Digikey when I am really concerned about quality. So I would purchase caps, resistors, solder, leads, or anything else that I really want to depend on from them (e.g. DigiKey). I am leaning towards stocking some items like resistors, capacitors, and LEDs from eBay or one of the suppliers I previously mentioned for use in prototyping or personal projects. In the sticky topic that wildred linked several individuals mention purchasing kits for items like these from eBay or Aliexpress.

In EEVBlog #168 Dave mentions @23:50 about getting mixed bags on eBay (for things like ceramic, eletrolytic, tantalum, various leds, etc). (Though he didn't mention specifically about sellers on eBay located in China).

As some expressed concern about purchasing from eBay and I believe specifically from suppliers in China, I was wondering how suppliers like taydaelectronics, dipmicro, or futurlec compare to those retailers on eBay. This was the intent of my original question. Would you place them in the same category as Chinese sellers on eBay or at a level in between places like DigiKey and eBay sellers from China?

Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: amitchell on August 12, 2016, 10:22:23 pm
Its hard to beat Digikey to Canada.

$8 fedex overnight for orders under $200 and no additional fees at your door.

Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: rstor22 on August 12, 2016, 11:39:20 pm
Its hard to beat Digikey to Canada.

$8 fedex overnight for orders under $200 and no additional fees at your door.



Take for example the following 200pcs capacitor kit which sells for $6.03 CDN (free shipping):
http://www.ebay.ca/itm/200pcs-DIY-15-Values-0-1uF-220uF-Electrolytic-Capacitor-Assortment-Kit-with-Box-/172270962448?hash=item281c264710:g:vFgAAOSw7XZXhJn~ (http://www.ebay.ca/itm/200pcs-DIY-15-Values-0-1uF-220uF-Electrolytic-Capacitor-Assortment-Kit-with-Box-/172270962448?hash=item281c264710:g:vFgAAOSw7XZXhJn~)

A similar assortment of capacitors from DigiKey selecting the cheapest ones with the lowest and second lowest voltage ratings is $42.92 with shipping and taxes:
http://www.digikey.ca/short/3m2vr8 (http://www.digikey.ca/short/3m2vr8)
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: george graves on August 13, 2016, 12:27:31 am
Tayda ships from the US if you buy on the US website.

Do they have a different URL for the US site?  I couldn't seem to find it.
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: amitchell on August 13, 2016, 04:55:46 am
Its hard to beat Digikey to Canada.

$8 fedex overnight for orders under $200 and no additional fees at your door.



Take for example the following 200pcs capacitor kit which sells for $6.03 CDN (free shipping):
http://www.ebay.ca/itm/200pcs-DIY-15-Values-0-1uF-220uF-Electrolytic-Capacitor-Assortment-Kit-with-Box-/172270962448?hash=item281c264710:g:vFgAAOSw7XZXhJn~ (http://www.ebay.ca/itm/200pcs-DIY-15-Values-0-1uF-220uF-Electrolytic-Capacitor-Assortment-Kit-with-Box-/172270962448?hash=item281c264710:g:vFgAAOSw7XZXhJn~)

A similar assortment of capacitors from DigiKey selecting the cheapest ones with the lowest and second lowest voltage ratings is $42.92 with shipping and taxes:
http://www.digikey.ca/short/3m2vr8 (http://www.digikey.ca/short/3m2vr8)

I am not sure you can fairly compare the two, maybe someone has experience with those ebay caps? I prefer to purchase the best I can get, overall each piece is generally inexpensive, and I feel it comes with peace of mind.

Its also much easier to just deal with one or two places that cover all your bases, the time savings and convenience are worth more than a bit of cost savings imo. Maybe that's another way to think of it?
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: Audioguru on August 13, 2016, 12:52:46 pm
An ebay capacitor kit of manufacturer's rejects or old worn out used ones? Or a Digikey assortment of the highest quality ones? They do not compare.
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: rstor22 on August 13, 2016, 01:02:12 pm
I am not sure you can fairly compare the two, maybe someone has experience with those ebay caps? I prefer to purchase the best I can get, overall each piece is generally inexpensive, and I feel it comes with peace of mind.

Its also much easier to just deal with one or two places that cover all your bases, the time savings and convenience are worth more than a bit of cost savings imo. Maybe that's another way to think of it?

The comparison was in terms of price (as you mentioned their low shipping cost). If my concern is quality, I would choose caps from Digikey over some unknown source on eBay. However my main concern is not quality but to have a basic cheap stock of components such as these for prototyping and personal projects. As electrolytic caps degrade over time I would be less concerned with replacing the cheaper ones.
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: Kalvin on August 13, 2016, 01:16:26 pm
Typically one can use the cheap components like electrolytic capacitors, resistors, ceramic caps, diodes, transistors, etc. for prototyping purposes. After the prototyping is done, just replace the cheap elcos and other cheap components with the better quality as needed. I don't see any problem using cheaper components during the prototyping and proof of concept phase if the precision, tempco etc. are not an issue and one keeps in mind that the component quality may be less than optimal. Most of the time it doesn't matter. For the high precision instrumentation etc. you will want to use quality components anyway, but you can use the cheaper components for the functional blocks that do not require absolute precision and accuracy. You just need to know what you are doing.
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: rstor22 on August 13, 2016, 01:20:40 pm
I've also gotten stuff off DipMicro they are fine and cheap. Basically they seem to buy there stuff from Chinese suppliers, read some of the descriptions of their products.

Thank you. This is what I was wondering: would stores like taydaelectronics, dipmicro, or futurlec or kits sold on Amazon like Joes Knows Electronics or Ecowsera source their goods from the same suppliers where Chinese Ebay sellers source from... 
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: Kalvin on August 13, 2016, 01:35:35 pm
I've also gotten stuff off DipMicro they are fine and cheap. Basically they seem to buy there stuff from Chinese suppliers, read some of the descriptions of their products.

Thank you. This is what I was wondering: would stores like taydaelectronics, dipmicro, or futurlec or kits sold on Amazon like Joes Knows Electronics or Ecowsera source their goods from the same suppliers where Chinese Ebay sellers source from...
It can also be possible that the Amazon sellers buy from tayda/dipmicro/futurlec etc. and just resell the stuff with some margin.
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: rstofer on August 13, 2016, 03:55:12 pm
I buy all my components from mainline suppliers (DigiKey, Mouser, Allied, Newark) and, to date, I have only bought two bags of stuff from a second tier supplier on Amazon.
When I order from DigiKey it always ships the same day.  I usually have my parts in two days, three at the outside.  I have a fairly short attention span, it's good to get the parts while I am still thinking about the project.

I usually buy enough parts to build two or three of whatever I am playing with.  That way I have extras in case the smoke escapes and I also build up a small inventory.  I did buy a resistor and capacitor kit from Jameco mostly to get the cabinet.  I don't know how long I have had them but at least 12 years, maybe longer.  When I buy axial resistors, I order in lots of 100 and use the extras to refill the cabinet.

SMD is a whole 'nother story.  I buy extras but I don't have a rational way to store them other than that reel of 4000 0.1 ufd ceramic which I will never use up.  Too many values, not enough drawers, whatever.  I should probably get a bunch of pill bottles but I still have to invent a labeling system.

Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: dannyf on August 13, 2016, 04:10:28 pm
I stock minimum parts:

1) resistors, mostly 1k/10k/100k variants + some assorted resistors;
2) capacitors: 220u, 47u, 22u, 4.7u, and .1u capacitors;
3) transistors: mostly 2n5401/5551, some N-most (irf510/540, 2n7002).
4) voltage regulators: 5v, 3.3v, 2.5v, 2v.
5) opamps: ne5532, tda1308, TL0x2.
6) logic IC: HC132, 164, 393, 595, 4060, 4020, 4040.

plus some special parts. amongst them, 80% of my needs are taken care of and they can be acquired fairly inexpensively.

My advice to you is to figure out what you want to do, and figure out the most common parts that can get it done. Avoid buying specialty parts as much as you can.

For example, if I wanted to use a cmos opamp and i only have ne5532. I would then put a 2n7000/7002 pair in front of ne5532 and form cmos amp - I actually built a pico-ammeter with 7002s + LM358 that way.

It is much more fun to do that than using a (proper) LMC6042/6062 or 6001.
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: JoeN on August 14, 2016, 05:50:18 am
Tayda ships from the US if you buy on the US website.

Do they have a different URL for the US site?  I couldn't seem to find it.

The U.S. website is www.taydaelectronics.com (http://www.taydaelectronics.com) like was mentioned before.  They also have a selling account on eBay and when I have bought from their account on eBay they ship from Thailand which takes longer.  From www.taydaelectronics.com (http://www.taydaelectronics.com) they ship from Colorado.  Don't ask me why, I have no idea.
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: george graves on August 14, 2016, 07:36:44 am
Thanks.  I just noticed their shipping on www.taydaelectronics.com (http://www.taydaelectronics.com) and it looked like china shipping to me.  But that's for the heads up.

I asked because, the 7-16 days shipping as they quote below.  Nothing that is shipping inside the US would ever take 16 days (other then maybe media mail, but that's only for books cd's and DVD's and such)

Quote
Standard 7 - 16 Days $1.13
Economic Express 6 - 9 Days $4.13
DHL Express 2 - 4 Days $16.00
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: JoeN on August 14, 2016, 08:52:38 am
Thanks.  I just noticed their shipping on www.taydaelectronics.com (http://www.taydaelectronics.com) and it looked like china shipping to me.  But that's for the heads up.

It always comes to me from Colorado in a domestic shipment in a brown envelope, usually with a pink bubble wrap sleeve inside it and then envelopes of parts inside that.  It is never that long of a shipment but maybe it takes a week usually?  I have always had the impression they buy their parts in bulk from Thailand and then have some shipment arrangement in Colorado.  It's probably some guy's basement, but it works.  Maybe they quote the longer time if they are awaiting parts but it has never, ever taken that long for me.

Found this on their website:

http://www.taydaelectronics.com/about (http://www.taydaelectronics.com/about)

Where are we

Tayda Electronics corporate offices are in Bangkok, Thailand.  We also have warehouse,  shipping and logistics centers both in Bangkok and in Colorado, USA.  Our software developers and various marketing staff are in Durango, Colorado USA.  Our Electronics kit testers are in Durango and Bangkok.
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: Stuartambient on August 14, 2016, 06:35:47 pm
I have to go back and look for the thread but remember it being said by 1 or 2 members Tayda  takes a while on shipping in the U.S..
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: ZeTeX on August 15, 2016, 11:05:42 pm
Tayda ships from Thailand always - not US.
Title: Re: Where to purchase cheap components to have a basic stock for prototyping
Post by: nanofrog on August 16, 2016, 01:41:02 am
Tayda ships from Thailand always - not US.
True, but it can appear that way to those that aren't aware of their shipping methods (bulk container sent to a reshipping company here in the US, which sends the individual orders by USPS).